[Federal Register: July 29, 2004 (Volume 69, Number 145)]
[Proposed Rules]
[Page 45505-45534]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr29jy04-33]
[[Page 45505]]
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Part V
Department of Energy
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Office of Energy Efficiency and Renewable Energy
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10 CFR Part 432
Energy Conservation Program: Test Procedures for Distribution
Transformers; Proposed Rule
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DEPARTMENT OF ENERGY
Office of Energy Efficiency and Renewable Energy
10 CFR Part 432
[Docket No. EE-TP-98-550]
RIN 1904-AA85
Energy Conservation Program: Test Procedures for Distribution
Transformers
AGENCY: Office of Energy Efficiency and Renewable Energy, Department of
Energy.
ACTION: Supplemental notice of proposed rulemaking and public meeting.
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SUMMARY: The Department of Energy (DOE or the Department) previously
published a notice of proposed rulemaking to adopt test procedures for
measuring the energy efficiency of distribution transformers under the
Energy Policy and Conservation Act (EPCA or the Act), definitions to
delineate the products covered by the test procedures and provisions
(including a sampling plan) for implementing the test procedures. The
Department now proposes to adopt revised test procedures for
distribution transformers, primarily based upon existing industry
standards. The proposed rule also contains revised definitions and
provisions to implement the test procedures, calculation methods that
manufacturers could use to determine the efficiency of some of their
models, and enforcement methods for distribution transformers. The
Department would use the test procedures in evaluating whether, and to
what extent, energy conservation standards are warranted for
distribution transformers. If standards are promulgated, then these
test procedures and the other provisions proposed today would be used
to determine efficiency and assess compliance of the transformers
subject to the standards.
DATES: The Department will hold a public meeting on the matters
addressed in this document, on Monday, September 27, 2004, beginning at
9 a.m. in Room 1E-245, in Washington, DC. The Department must receive
requests to speak at the meeting, and a signed original and electronic
copy of statements to be given at the meeting, no later than 4 p.m.,
Monday, September 13, 2004. The Department will accept written
comments, data, and information in response to this notice before or
after the public meeting, but no later than Monday, November 8, 2004.
See section IV, ``Public Participation,'' of this notice for details.
ADDRESSES: You may submit comments, identified by docket number EE-TP-
98-550 and/or RIN number 1904-AA85, by any of the following methods:
Federal eRulemaking Portal: http://www.regulations.gov.
Follow the instructions for submitting comments.
E-mail: DistTransformersTP-SNOPR@ee.doe.gov. Include EE-
TP-98-550 and/or RIN 1904-AA85 in the subject line of the message.
Mail: Ms. Brenda Edwards-Jones, U.S. Department of Energy,
Building Technologies Program, Mailstop EE-2J, SNOPR for Distribution
Transformer Test Procedures, EE-TP-98-550 and/or RIN 1904-AA85, 1000
Independence Avenue, SW., Washington, DC, 20585-0121. Telephone: (202)
586-2945. Please submit one signed original paper copy.
Hand Delivery/Courier: Ms. Brenda Edwards-Jones, U.S.
Department of Energy, Building Technologies Program, Room 1J-018, 1000
Independence Avenue, SW., Washington, DC, 20585.
Instructions: All submissions received must include the agency name
and docket number or Regulatory Information Number (RIN) for this
rulemaking. For detailed instructions on submitting comments and
additional information on the rulemaking process, see section IV of
this document (Public Participation).
Docket: For access to the docket to read background documents or
comments received, go to the U.S. Department of Energy, Forrestal
Building, Room 1J-018 (Resource Room of the Building Technologies
Program), 1000 Independence Avenue, SW., Washington, DC, (202) 586-
9127, between 9 a.m. and 4 p.m., Monday through Friday, except Federal
holidays. Please call Ms. Brenda Edwards-Jones at the above telephone
number for additional information regarding visiting the Resource Room.
Please note: The Department's Freedom of Information Reading Room
(formerly Room 1E-190 at the Forrestal Building) is no longer housing
rulemaking materials.
FOR FURTHER INFORMATION CONTACT: Cyrus Nasseri, Project Manager, Test
Procedures for Distribution Transformers, Docket No. EE-TP-98-550, U.S.
Department of Energy, Energy Efficiency and Renewable Energy, Building
Technologies Program, EE-2J, 1000 Independence Avenue, SW., Washington,
DC 20585-0121, (202) 586-9138, E-mail: cyrus.nasseri@ee.doe.gov.
Francine Pinto, Esq., or Thomas B. DePriest, Esq., U.S. Department
of Energy, Office of General Counsel, GC-72, 1000 Independence Avenue,
SW., Washington, DC 20585-0121, (202) 586-9507, E-mail:
Francine.Pinto@hq.doe.gov, or Thomas.DePriest@hq.doe.gov.
SUPPLEMENTARY INFORMATION:
I. Introduction
A. Authority and Background
B. Summary of the Proposed Rule
II. Discussion
A. The Test Procedure for Distribution Transformers
1. General Discussion
2. Reference Conditions
B. Transformers Subject to the Test Procedure
1. Background
2. Changes to, and retention of, provisions in the 1998 proposed
rule
3. Exclusions discussed in the 1999 reopening notice
4. Additional exclusions drawn from NEMA TP 1
5. Definitions of excluded transformers
C. Basic Model
D. Manufacturer's Determination of Efficiency
E. Enforcement Procedures
F. New Part 432
III. Procedural Requirements
A. Review Under Executive Order 12866
B. Review Under the Regulatory Flexibility Act
C. Review Under the Paperwork Reduction Act
D. Review Under the National Environmental Policy Act
E. Review Under Executive Order 13132
F. Review Under Executive Order 12988
G. Review Under the Unfunded Mandates Reform Act of 1995
H. Review Under the Treasury and General Government
Appropriations Act, 1999
I. Review Under Executive Order 12630
J. Review Under the Treasury and General Government
Appropriations Act, 2001
K. Review Under Executive Order 13211
L. Review Under Section 32 of the Federal Energy Administration
Act of 1974
IV. Public Participation
A. Attendance at Public Meeting
B. Procedure for Submitting Requests to Speak
C. Conduct of Public Meeting
D. Submission of Comments
I. Introduction
A. Authority and Background
Part C of Title III of the Energy Policy and Conservation Act
(EPCA) provides for an energy conservation program for certain
industrial equipment. (42 U.S.C. 6311-6317) Section 346 of EPCA states
that the Secretary of Energy (Secretary) must prescribe testing
requirements and energy conservation standards for those ``distribution
transformers'' for which the Secretary determines that standards
``would be technologically feasible and economically justified, and
would result in significant energy savings.'' (42 U.S.C. 6317(a)) On
October 22, 1997, the
[[Page 45507]]
Department issued a notice setting forth its determination (hereafter
referred to as the ``Determination'') that, based on the best
information currently available, energy conservation standards for
electric distribution transformers appear to be technologically
feasible and economically justified, and are likely to result in
significant energy savings. 62 FR 54809. The Determination was based,
in part, on analyses conducted by the Oak Ridge National Laboratory
(ORNL), as explained in reports issued in July 1996 and September
1997.\1\ 62 FR at 54811-54816.
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\1\ The titles and references for these reports are
``Determination Analysis of Energy Conservation Standards for
Distribution Transformers, ORNL-6847'' and ``Supplement to the
`Determination Analysis' (ORNL-6847) and Analysis of NEMA Efficiency
Standard for Distribution Transformers, ORNL-6925.''
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The Department subsequently began the process for its adoption of
test procedures for distribution transformers. On February 10, 1998,
the Department held a public workshop (1998 workshop) to discuss the
following issues: (a) Adoption of national and international consensus
standards as the test procedures for determining the energy efficiency
of distribution transformers, (b) defining the transformers that the
test procedures will cover, (c) imposition of a burden on industry,
especially on manufacturers, with additional testing and data
processing, (d) definition of ``basic model'' for distribution
transformers, (e) sampling plan for units to be tested, (f) selection
of an energy consumption measure for distribution transformers, (g)
selection of reference temperatures, (h) requirements for applying
corrections to measurement data, and (i) requirements for quality
assurance in testing. The Department also gave interested parties an
opportunity to submit comments on these issues.
In 1998, the National Electrical Manufacturers Association (NEMA)
published ``NEMA Standards Publication No. TP 2-1998, Standard Test
Method for Measuring the Energy Consumption of Distribution
Transformers,'' (NEMA TP 2) a publication that extracts and presents
the pertinent parts of the current industry standards for distribution
transformer efficiency testing. NEMA TP 2 presents a weighted average
method to use to compute the energy efficiency of transformers, in
order to demonstrate compliance with the efficiency levels in NEMA
Standard TP 1-1996 (NEMA TP 1).\2\ Comments received at the 1998
workshop, written comments associated with this workshop, and NEMA TP 2
formed the basis for preparing the November 12, 1998, Notice of
Proposed Rulemaking (the ``1998 proposed rule''). 63 FR 63359.
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\2\ NEMA TP 1 contains suggested efficiency levels. Its full
name and title are ``NEMA Standards Publication No. TP 1-1996, Guide
for Determining Energy Efficiency for Distribution Transformers.''
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In the 1998 proposed rule, the Department proposed to adopt test
procedures that (1) it would use to evaluate distribution transformers
for efficiency standards, and (2) manufacturers and DOE would use to
determine the efficiency of any transformers which the standards
covered. DOE proposed to incorporate by reference as its test
procedures, provisions from either Institute of Electrical and
Electronics Engineers (IEEE) Standards C57.12.90-1993 and C57.12.91-
1993 (using IEEE C57.12.00-1993 as an additional reference source), or
NEMA TP 2. The 1998 proposed rule also included proposed definitions of
``distribution transformer'' and related terms, of terms used in the
test procedure provisions, and of ``basic model,'' and proposed a
sampling plan for applying the test procedures to perform compliance
testing. The sampling approach was based on the plan for compliance
testing in 10 CFR part 430, which contains energy efficiency
requirements for consumer products, but with modifications geared to
transformers and a minimum sample size of five units. The Department
selected this approach because it appeared to provide a satisfactory
balance between assuring accuracy of efficiency ratings for
distribution transformers and minimizing the test burden on
manufacturers. The Department also sought comment on three alternative
compliance approaches for basic models produced in small numbers.
DOE held a public hearing on January 6, 1999, on the 1998 proposed
rule and received nine written comments. After reviewing the oral and
written comments, DOE concluded that the comments raised a number of
significant issues that required additional analysis. On June 23 1999,
the Department reopened the comment period on the 1998 proposed rule,
64 FR 3343, (the ``1999 reopening notice'') to provide an opportunity
for additional public comment on the following issues: (a) The
suitability of NEMA TP 2 for adoption as the DOE test procedure; (b)
the adequacy of stakeholder opportunity to review NEMA TP 2; (c) the
transformers covered under the definition of ``distribution
transformer;'' (d) the suitability of the definition of ``basic model''
for the purpose of grouping transformers to limit the test burden; and
(e) the appropriateness of the proposed sampling plan and a number of
alternatives for demonstrating compliance. The Department received five
comments in response to the 1999 reopening notice and two additional
comments during the development of today's proposed test procedure.
These comments are addressed throughout section II of this supplemental
notice of proposed rulemaking.
Finally, concurrent with this rulemaking, the Department has
evaluated the establishment of energy conservation standards for
distribution transformers. On October 2, 2000, the Department made
available a Framework Document for Distribution Transformer Energy
Conservation Standards Rulemaking, which was the subject of a public
workshop on November 1, 2000, and on which stakeholders submitted
written comments before and after the workshop. 65 FR 59761 (October 6,
2000). Thereafter, the Department visited manufacturers of distribution
transformers and posted on DOE's Web site \3\ several draft reports
concerning the development of standards for these transformers. The
next step in this process is the Department's issuance of an Advance
Notice of Proposed Rulemaking (ANOPR) for distribution transformer
standards. The Department expects to publish the ANOPR in the Federal
Register later this year.
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\3\ http://www.eere.energy.gov/ buildings/appliance--standards/
commercial/dist--transformers.html.
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B. Summary of the Proposed Rule
In today's notice, the Department proposes to adopt a new test
procedure for determining the energy efficiency of distribution
transformers. The test procedure consists primarily of test methods
contained in IEEE Standards C57.12.90-1999 and C57.12.91-2001, and NEMA
TP 2. Initially, the Department would use the test procedure to test
distribution transformers for which it is considering energy
conservation standards. If DOE promulgates minimum efficiency
standards, the Department would then require manufacturers to use the
test procedure to determine compliance with the standards and as a
basis for efficiency representations for transformers they produce that
the standards cover. The Department would also use the test procedure
in enforcement proceedings concerning compliance with standards or
labeling requirements.
The proposed test procedure is a ``stand alone'' document. Thus,
the
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language of today's proposed rule sets forth all testing requirements,
without reference to other sources, for determining the energy
efficiency of distribution transformers. The measurement of electric
power consumed by the transformer is in the form of no-load and load
losses. The proposed rule specifies methods with which to measure the
following quantities: Temperature of the windings and the core,
current, voltage, waveform, and direct current resistance of the
windings. The proposed rule also contains definitions that establish
which transformers the test procedure covers and that clarify terms
used in the test procedure. In addition, to reduce the number of
transformers that manufacturers would have to test, the Department
proposes to define ``basic model,'' proposes a sampling plan, and
proposes to allow manufacturers to use alternative methods, other than
testing, for determining the efficiency of some basic models. Finally,
the proposed rule also sets forth enforcement procedures, including a
testing protocol, for distribution transformers.
The Department's adoption of uniform test procedures would not
necessarily mean that it would adopt a single efficiency standard or
set of labeling requirements for all transformers that today's proposed
rule covers. In the separate rulemaking proceeding concerning energy
conservation standards for distribution transformers, the Department
intends to divide such transformers into classes and may conclude that
standards are not warranted for some classes of transformers that are
within the scope of today's test procedure. Furthermore, for the
classes for which DOE decides to adopt standards, it may create a
separate standard for each class of products where the record indicates
the products include a utility or performance-related feature that
other products lack and that affects energy efficiency.
II. Discussion
A. The Test Procedure for Distribution Transformers
1. General Discussion
The Department developed today's proposed test procedure in order
to have a single primary reference standard that would clearly set
forth all testing requirements for the distribution transformers that
might be covered by an EPCA energy conservation standard. DOE adapted
virtually all of the provisions of the test procedure from NEMA TP 2
and the following four widely used IEEE standards: (1) IEEE C57.12.90-
1999, ``IEEE Standard Test Code for Liquid-Immersed Distribution, Power
and Regulating Transformers and IEEE Guide for Short Circuit Testing of
Distribution and Power Transformers,'' (2) IEEE C57.12.91-2001, ``IEEE
Standard Test Code for Dry-Type Distribution and Power Transformers,''
(3) IEEE C57.12.00-2000, ``IEEE Standard General Requirements for
Liquid-Immersed Distribution, Power and Regulating Transformers,'' and
(4) IEEE C57.12.01-1998, ``IEEE Standard General Requirements for Dry-
Type Distribution and Power Transformers Including those with Solid
Cast and/or Resin Encapsulated Windings.'' \4\
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\4\ This discussion does not address section 7 of NEMA TP 2,
``Demonstration of Compliance,'' which is discussed in section II-D.
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IEEE C57.12.90-1999 and IEEE C57.12.91-2001 address tests and
measurements leading to the energy consumption and efficiency values.
IEEE C57.12.00-2000 and C57.12.01-1998 complement IEEE C57.12.90-1999
and IEEE C57.12.91-2001 by specifying requirements such as measurement
tolerances, which are critical for defining the testing conditions.
Each of these four IEEE standards contains different elements of the
energy efficiency test procedure for distribution transformers, as well
as material not required for efficiency testing. Thus, if the
Department were to prescribe the transformer test procedure by
reference to these sources, it would require the user to consult
several references, and applicable sections and clauses within those
references, in order to construct a single test procedure. DOE believes
that having a single, reference test procedure document would enhance
the convenience to users and reduce the potential for misinterpretation
of testing requirements.
Because NEMA TP 2 was designed to be a document that would contain
all applicable testing provisions, the Department considered adopting
it as the DOE test procedure. 63 FR at 63362, 63370-72; 64 FR at 33431-
32. The Department therefore reviewed NEMA TP 2 and compared it with
the similar material in the IEEE standards. NEMA TP 2 excerpts the
information pertinent to transformer efficiency testing from these
standards (using earlier editions of the standards), and presents it in
abbreviated form. As a result of its review, the Department determined
that NEMA TP 2 lacks the clarity and detail required in a regulatory
document, and also contains a number of technical and typographical
errors. Consequently, DOE is not proposing to use it as the DOE test
procedure. Nevertheless, because NEMA TP 2 brings transformer
efficiency testing provisions into a single document, the Department
used it to develop today's proposed test procedure, which is designed
to approach the level of detail of the IEEE standards. The following
are examples of the ways in which the Department found NEMA TP 2 to be
unsatisfactory for use as the DOE test procedure, and in which today's
proposed test procedure differs from NEMA TP 2:
(1) Section 3 in NEMA TP 2, Resistance Measurements, contains
insufficient detail, particularly in describing instrumentation. The
proposed test procedure provides greater detail on the description of
instrumentation, especially resistance bridges and their operating
equations, and provides more information on temperature measurements.
(2) Figures 2 and 3 in NEMA TP 2 are too crowded with information.
As a result, the graphics and print symbols are too small, some to the
point of being unreadable. The proposed test procedure seeks to improve
the value of the diagrams, by incorporating four simplified diagrams
instead of two.
(3) Table 3 of NEMA TP 2 lacks a descriptive title, the title of
Table 3's first column should be ``Resistance to be Measured,'' and the
titles of the remaining three columns should each be followed by the
word ``Method.'' In addition, Table 3's identification of the ranges
covered by various methods does not reflect the capabilities of modern
instruments. Resistance meters are available to measure resistances on
a four-terminal basis below 10 ohms, and voltmeter-ammeter methods are
useable above 100 ohms. Hence, today's proposed rule does not contain a
table that is a counterpart to Table 3, and but instead sets forth in
narrative form the approximate ranges for the use of each method.
(4) Equation (2) for phase angle correction, in section 4.1.4 of
NEMA TP 2, is incorrect. The equation should be Pc = Pm - VmAm (Wd - Vd
+ Cd ) sin f, where f = cos-1(Pm/VmAm). Also, NEMA TP 2
fails to define the polarities of the phase angle errors. For example,
Wd is positive if the phase angle between the voltage and current
phasors as sensed by the wattmeter is smaller than the true phase
angle. The Department believes that today's proposed test procedure
correctly addresses these points based on the provisions of IEEE
C57.12.90 and C57.12.91. The Department also notes that, although
equation (4-3) in section 4.5.3.2 of the proposal does not appear in
the IEEE standards, it provides information similar to that in Table 1
of
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the IEEE C57.12.90 as to whether phase angle correction is required.
(5) Section 4.3.4.2 of NEMA TP 2 lacks some of the steps needed to
calculate the load loss from the previously measured quantities. The
test procedure proposed in today's notice includes all of the necessary
steps.
2. Reference Conditions
To establish a standard basis for test results, today's proposed
test procedure specifies reference conditions for testing and rating
the efficiency of distribution transformers. In particular, the test
procedure would require that equipment efficiencies be rated at the
loading levels of 35 percent for low-voltage, dry-type models and 50
percent for medium-voltage, dry-type and all liquid-immersed models, as
specified in NEMA TP 2.
The Department recognizes that considerations other than efficiency
commonly require manufacturers to test transformers at 100 percent of
their rated load. Today's proposed test procedure includes analytical
techniques that a manufacturer could use, where it has tested a
transformer at 100 percent of its rated load, to calculate the
transformer's efficiency at the loading point specified in the test
procedure. Thus, the manufacturer would not have to test the
transformer at both the loading point prescribed in the test procedure
and at 100 percent of its rated load. Moreover, once today's test
procedure has been implemented, should experience indicate that the
loading levels specified in the test procedure are not appropriate for
rating some distribution transformers, the Department would consider
adopting different loading levels for those types of transformers.
B. Transformers Subject to the Test Procedure
1. Background
In essence, section 346 of EPCA directs the Department to consider
whether an energy conservation program for ``distribution
transformers'' is warranted. (42 U.S.C. 6317(a)(1)) However, the
statute does not define ``distribution transformer.'' In the
Determination notice, the Department interpreted the term
``distribution transformer'' in section 346 of EPCA to mean ``all
transformers with a primary voltage of 480 V to 35 kV, a secondary
voltage of 120 V to 480 V, and a capacity of either 10 to 2500 kVA for
liquid-immersed transformers or 0.25 kVA to 2500 kVA for dry-type
transformers,'' except for transformers which are not continuously
connected to a power distribution system as a distribution transformer.
62 FR at 54811. The 1998 proposal proposed to adopt essentially this
same definition, except that the upper limit on secondary voltage was
increased from 480 V to 600 V because the Department learned that
industry typically classifies transformers with a secondary voltage up
to 600 V as distribution transformers. 63 FR 63370 (November 12, 1998).
The primary reason for defining distribution transformer in this
rulemaking is to identify the transformers to which the Department's
test procedure would apply. As indicated above, initially the test
procedure would apply only to those transformers that the Department is
evaluating for standards. Thus, the issue of which products should be
within today's proposed definition of distribution transformer is
identical to the issue of which products the Department will evaluate
for standards. As the following discussion indicates, in developing
this definition, the Department has considered information received in
its rulemaking on transformer standards. The Department has also based
the proposed definition on consideration of the nature of transformers
that are commonly understood to be ``distribution transformers,'' and
of whether energy conservation standards for such a transformer would
result in significant energy savings.
2. Changes to, and Retention of, Provisions in the 1998 Poposed Rule
Today's proposal eliminates from the definition of distribution
transformer the 1998 proposed rule's lower limits on primary voltage
and secondary voltage of 480 V and 120 V, respectively. In the 1999
reopening notice, the Department stated that it did not intend to
increase the lower limit on primary voltage to 600 V. 64 FR at 33432-
33. In the proceedings on the development of standards, NEMA strongly
advocated that the Department have no lower limits on the primary and
secondary voltages of the transformers it evaluates for standards,
reflecting the coverage of NEMA TP 1. (NEMA, No. 35 at p. 4 and No. 36
at p.2) \5\ Consistent with NEMA's position, the Department is
concerned that defining a distribution transformer as having a minimum
primary and/or secondary voltage may result in eliminating distribution
transformers from consideration in the standards rulemaking. The
Department also believes that it can include other elements in its
definition of ``distribution transformer'' to ensure that its test
procedures and standards for transformers would cover only products
that are truly ``distribution transformers.'' Therefore, in accordance
with its planned approach in the standards rulemaking, and to ensure
that its test procedure will apply to all distribution transformers
evaluated for standards, the Department has removed the lower bounds on
primary and secondary voltage from the definition of distribution
transformer that the Department is proposing today.
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\5\ No. 35 and No. 36 refer to the numbers of the written
comments and supporting documents included or referenced in the
docket for this rulemaking (Docket Number EE-TP-98-550). Numbers 4
and 2 refer to the cited page numbers in those written comments.
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With regard to the 1998 proposed rule's capacity criteria for
defining a distribution transformer (10 kVA to 2500 kVA for liquid-
immersed units and 0.25 kVA to 2500 kVA for dry-type units), the 1999
reopening notice stated the Department's intent to increase the lower
capacity limit for dry-type units to either 1, 5, 10 or 15 kVA. 64 FR
at 33433. The Department understands, based on information it has
received in the course of its work on the standards rulemaking, that 5
and 10 kVA dry-type transformers are normally not used in the
distribution of electric energy. Therefore, today's definition of
distribution transformer proposes a lower capacity limit for dry-type
units of 15 kVA. The Department, however, is still considering in the
standards rulemaking whether to evaluate for standards dry-type
transformers with ratings of 5 and 10 kVA. Therefore, DOE seeks comment
in the instant rulemaking on whether such transformers are properly
classified as distribution transformers, and whether it should adopt
one of these levels as the lower capacity limit for dry-type units in
the definition of distribution transformer, instead of the 15 kVA level
in today's proposed rule.
The 1998 proposed rule's definition also excluded ``transformers
which are not designed to be continuously connected to a power
distribution system as a distribution transformer * * * [such as
certain specifically identified types of transformers] and other
transformers which are not designed to transfer electrical energy from
a primary distribution circuit to a secondary distribution circuit, or
within a secondary distribution circuit, or to a consumer's service
circuit.'' 63 FR at 63370. The Department is concerned that these
criteria may be too vague and imprecise, and subject to
misinterpretation, and may fail to establish clearly which transformers
are and are not covered under EPCA as
[[Page 45510]]
distribution transformers. This would be particularly true for parties
that work with distribution transformers in non-utility related
applications, where much of the terminology in these criteria--for
example, phrases like ``to a consumer's service circuit''--is
inapplicable and may be meaningless. In the standards rulemaking, NEMA
has advocated that the Department adopt a definition of distribution
transformer that aligns with the scope of NEMA TP 1. (NEMA No. 35 at p.
4) The scope provision of NEMA TP 1 states that the standard applies to
transformers meeting numerical criteria of the types discussed above--
for example, capacity in kVA--and then lists specific types of
transformers to which the standard does not apply. (NEMA TP 1 at p. 1)
Today's proposed rule follows this approach in defining
distribution transformer and is similar to the scope provision of NEMA
TP 1. In addition to having numerical criteria, the proposed definition
lists types of transformers that are made for applications unrelated to
the distribution of electricity, or for which standards would not
produce significant energy savings, and provides that they are not
``distribution transformers.'' Such a definition is clearer, more
precise and less subject to misinterpretation than the 1998 proposed
rule's definition. Although the list of excluded transformers is quite
similar to that in NEMA TP 1, DOE has modified it slightly.\6\ The
proposed rule also contains a definition for each of these excluded
transformers.
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\6\ Today's proposed definition of ``distribution transformer''
excludes almost verbatim 13 of the 17 types of transformers
specifically excluded from NEMA TP 1. (The list of exclusions from
TP 1 appears on page one of TP 1.) NEMA TP 1, however, also excludes
``transformers designed for high harmonics'' and ``harmonic
transformers,'' but today's proposed definition addresses these
transformers by excluding ``harmonic mitigating transformers'' and
certain ``K-factor'' (harmonic tolerating) transformers. In
addition, although TP 1 excludes ``retrofit transformers'' and
``regulation transformers,'' the proposed rule excludes neither--the
former for reasons discussed in section II-B-3 in the text and the
latter because DOE believes they are more accurately described as
``regulating transformers,'' which are already in the list of
exclusions in NEMA TP 1 and the proposed rule. In addition, NEMA TP
1 excludes ``non-distribution transformers, such as UPS
[uninterruptible power supply] transformers.'' Although the proposed
definition excludes uninterruptible power supply transformers, the
remainder of this exclusion is vague, and the Department believes
that including it in the regulations would undercut the precision
achieved by listing specific types of transformers as being excluded
from the definition of ``distribution transformer.''
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The 1998 proposed rule identified the following transformers as not
being distribution transformers: grounding transformers, machine-tool
(control) transformers, regulating transformers, testing transformers,
and welding transformers. 63 FR at 63370. They were not addressed
further in either the comments DOE received in this rulemaking or the
1999 reopening notice and they are listed as exclusions in the scope
provision of NEMA TP 1. For all of these reasons, they are excluded
from being ``distribution transformers'' in today's proposed rule.
The 1998 proposed rule also excluded ``converter and rectifier
transformers with more than two windings per phase'' from the
definition of distribution transformer, and provided definitions for
these transformers. 63 FR at 63370. Comments on the 1998 proposed rule
and the 1999 reopening notice supported these exclusions, as well as
the exclusion of rectifier transformers with less than three windings.
(Alexander D. Kline, P.E., No. 14 at pp.1-2; NEMA, No. 15 at p. 2, No
21 at p. 5, and No. 28 at p. 5; Howard Industries, Inc., No. 18 at p. 3
and No. 27 at p. 2) The Department now believes that exclusion of
converter transformers is unnecessary. Today's proposed definition of
distribution transformer has an upper limit on capacity of 2500 kVA,
and it is the Department's understanding that a transformer connected
to a converter, i.e., a converter transformer, always has a capacity
far above this level. Thus, their capacity automatically excludes them
from the definition, and they need not be specifically excluded.
Rectifier transformers, however, often have a capacity below 2500 kVA,
but they are not connected to electric distribution systems and cannot
be readily tested for losses. See 64 FR at 33433 (and comments cited
there) and 63 FR at 63363. Therefore, in today's proposed rule they are
in the list of products not included as distribution transformers. The
Department is also proposing to adopt the definition of ``rectifier
transformer'' that was recently incorporated into IEEE C57.12.80-2002,
clause 3.379, rather than the definition proposed in the 1998 proposed
rule. The Department believes the IEEE definition will be more widely
understood and accepted, without any loss of technical precision.
3. Exclusions Discussed in the 1999 Reopening Notice
The 1999 reopening notice stated that the Department was also
inclined to exclude autotransformers, and transformers with tap ranges
greater than 15 percent, from the definition of distribution
transformer. 64 FR at 33433-34. The notice identified comments on the
1998 proposed rule that advocated these exclusions and the Department's
reasons for favoring them. Some of the comments in response to the
reopening notice supported the exclusions and none opposed them.
Therefore these exclusions are included in today's proposed rule.
The Department also discussed in the 1999 reopening notice whether
it should exclude sealed or non-ventilated transformers, special
impedance transformers, and harmonic transformers from the definition
of distribution transformer. 64 FR at 33433-34. Each of these types of
transformer can be a distribution transformer. The Department stated
that it did not find persuasive the reasons commenters had advanced for
excluding these products, and that it intended to include them unless
it received information justifying their exclusion. As to non-
ventilated or sealed transformers, in response to the 1999 reopening
notice NEMA indicated that the unique features of these transformers
could pose a hardship for some manufacturers in testing them, and that
they are a small part of the market for distribution transformers.
(NEMA, No. 28 at p. 5) Given their small market share, it appears that
adopting standards for non-ventilated or sealed transformers would not
result in significant energy savings. For these reasons, the Department
has excluded them from today's proposed definition of distribution
transformer. DOE specifically requests comment, however, on whether
such exclusion is warranted.
With respect to special impedance distribution transformers, NEMA
states that they have much higher load losses than standard impedance
distribution transformers, and are designed to meet unusual performance
functions. (NEMA, No. 28 at p. 5) It also asserts that, because they
are relatively expensive to build, a lack of Federal efficiency
standards for these products would not cause them to be manufactured
and sold in increased volumes as substitutes for standard distribution
transformers that were subject to standards. (NEMA, No. 15 at p. 2) The
Department agrees with these points, and believes that the market for
these products is small and therefore regulating them would not result
in significant energy savings. For these reasons, today's proposed rule
excludes special impedance transformers from the definition of
distribution transformer.
DOE questions, however, the validity of NEMA's claim that any
transformer with an impedance outside the range of four to eight
percent is a special impedance transformer. (NEMA, No. 15 at p. 2) To
address this issue, the Department is proposing a definition for
[[Page 45511]]
``special impedance transformer'' that incorporates tables which set
forth the normal impedance range at each standard kVA rating for
liquid-immersed and dry-type transformers. DOE would consider any
transformer built with an impedance rating outside the ranges defined
as normal to be considered special impedance, and would exclude it from
the definition of distribution transformer. The Department specifically
requests comments on the normal impedance ranges shown in Tables 1 and
2 of today's proposed definition of ``special impedance transformer.''
Concerning harmonic distribution transformers, the Department
understands that there are two types of such transformers, those that
correct harmonics (harmonic mitigating transformers) and those that
simply tolerate, and do not correct, harmonics (called harmonic
tolerating or K-factor transformers). NEMA appears to assert that
neither type can be accurately tested to measure its efficiency. (NEMA,
No. 28 at p. 5) Although the Department has doubts about the validity
of this assertion, it agrees that harmonic mitigating transformers are
a special type of transformer. Furthermore, DOE believes that few of
them exist in the distribution system, regulating them would save
little energy, and they are sufficiently expensive to manufacture that
excluding them would be unlikely to result in a loophole if DOE adopted
standards for other transformers. DOE is, therefore, excluding harmonic
mitigating transformers from coverage in today's proposed rule.
The situation with harmonic tolerating (K-factor) transformers is
not so clear cut. These transformers are designed for use in industrial
situations where electronic apparatus can cause transformer losses that
are much higher than normal, and they are designed to accommodate such
losses without excessive temperature rise. But apparently it is
economically viable to use K-factor distribution transformers that have
low K-factors and relatively low efficiencies, in standard
applications, instead of regular distribution transformers with higher
efficiencies. The Department understands that, after the State of
Minnesota began to require that dry-type distribution transformers
installed in the state meet NEMA TP 1 efficiency levels, with an
exemption for K-factor and other transformers excluded from NEMA TP 1,
the installation of K-4 transformers increased substantially. These K-4
transformers had efficiencies that were not only below the levels
mandated by NEMA TP 1, they were also below the prevailing efficiency
levels of conventional distribution transformers that had been
installed in Minnesota prior to the State's adoption of NEMA TP 1. As
the K rating of K-factor transformers increases, however, they become
increasingly sophisticated and expensive to produce, and their market
share decreases. Thus, the risk that they would be used in place of
more efficient transformers declines, and the potential energy savings
from regulating them becomes insignificant.
The Department believes that K-13 is a reasonable demarcation
between K-factor distribution transformers that should be evaluated for
standards, and those for which standards appear to be unwarranted.
Above the K-4 rating, K-9 and K-13 are the next higher standard K-
factor rated transformers. The Department believes that while K-9
products are a small part of the market, it is uncertain whether,
absent standards for them, K-9 distribution transformers would be
substituted for transformers that are subject to standards (as happened
in Minnesota with K-4 transformers). The Department is aware that K-
factor transformers at K-13 and higher are significantly more expensive
than conventional transformers, and believes it is very unlikely they
would be purchased in place of distribution transformers subject to
standards. Thus, today's proposed definition excludes transformers with
a K-factor rating of K-13 or higher from the definition of a
distribution transformer. The definition includes K-factor transformers
with lower standard K-factors (K-4 and K-9), and DOE is evaluating them
for standards during its rulemaking on transformer standards. The
Department specifically invites comments on this issue.
Finally, information developed thus far in this proceeding
indicates that ``retrofit distribution transformer'' refers to any
transformer that replaces an existing distribution transformer. The
Department understands, however, that the term also may refer more
specifically to a transformer used in a distribution substation between
primary and secondary switchgear 30 to 50 years old, which must be
designed so that terminations are compatible with existing switchgear
and for which other features must differ from present-day designs.
Comments on the 1998 proposed rule asserted that the Department's
exclusions from the definition of distribution transformer should
provide for situations where existing distribution transformers cannot
be replaced with more efficient retrofit transformers, which generally
would be larger than, or configured differently from, the existing
transformers. (NEMA, No. 21 at pp. 5-6) In the 1999 reopening notice
the Department requested further, more detailed information on this
issue. 64 FR at 33434. The Department has not received such
information. Clearly retrofit distribution transformers are
distribution transformers, and the Department lacks a basis for
creating an exclusion for them in today's rule. In the standards
rulemaking, however, the Department intends to gather information on
the nature of, and dimensional restrictions for, these transformers, in
order to decide whether to treat them separately, as for example by
excluding them, by creating a separate class(es) or both, if the
Department adopts energy conservation standards for distribution
transformers.
4. Additional Exclusions Drawn From NEMA TP 1
In addition to excluding from its scope the types of transformers
discussed in sections II-B-2 and 3, NEMA TP1 also excludes drive
(isolation), traction-power, and uninterruptible power supply
transformers. Drive or isolation transformers are a type of
distribution transformer that is specially designed to accommodate
added loads of drive-created harmonics, and mechanical stresses caused
by an alternating current or direct current motor drive. Although
intrinsically they have higher losses than conventional distribution
transformers, DOE understands that they also have low sales volumes.
Therefore, the Department believes standards for this product would not
result in significant energy savings and is proposing to exclude them
from the definition of distribution transformer. In addition, the
Department notes that there are many kinds of drive transformers, and
development of the varied test methods and multiple standard levels
that would be necessary to achieve even the limited energy savings
possible for this product would be a complex undertaking.
As to traction-power transformers, these are designed to supply
power to railway trains or municipal transit systems, at frequencies of
16\2/3\ or 25 Hz in an alternating current circuit or as a rectifier
transformer. These transformers are excluded from today's proposed
definition of distribution transformer by provisions discussed above
that exclude both transformers operating at these low frequencies as
well as rectifier transformers. Therefore, DOE need not consider
whether to specifically exclude them.
[[Page 45512]]
Finally, an uninterruptible power supply transformer is not a
distribution transformer. It does not have as one of its functions
stepping down voltage, but rather it is a transformer that is a system
conditioning device. It is used as part of the electric supply system
for sensitive equipment that cannot tolerate system interruptions or
distortions, and counteracts such irregularities. Therefore, it is
excluded from the definition of distribution transformer in today's
proposed rule.
5. Definitions of Excluded Transformers
As noted above, today's proposed rule includes definitions for the
transformers DOE is proposing to exclude from today's rule. This will
help to make clear exactly which transformers the proposed rule covers.
For the following excluded transformers, DOE has taken the definitions
from IEEE C57.12.80-2002: autotransformers, grounding transformers,
machine-tool (control) transformers, non-ventilated transformers,
rectifier transformers, regulating transformers, and sealed
transformers. For K-factor transformers, DOE took the definition from
Underwriters Laboratories (UL) UL1561 and UL1562.
C. Basic Model
It is common for a manufacturer to make numerous models of a
product covered by EPCA, and under the Act each model is potentially
subject to testing for energy efficiency. In order to lessen the burden
of testing, the Department allows manufacturers to group product models
having essentially identical characteristics with respect to energy
consumption into a single family of models. The Department has used the
term ``basic model'' to represent such a family of models, consisting
of models of a product that are essentially the same in some or all of
the following respects: performance, physical, mechanical, electrical
and functional characteristics. For each type of product, the
Department's regulations set forth which of these characteristics
applies in identifying basic models. Each manufacturer can then test a
sufficient, representative sample of units of each basic model it
manufactures, and derive an efficiency rating for each basic model that
would apply to all models subsumed by that basic model. Components of
similar design can be substituted in a basic model without requiring
additional testing if the represented measures of energy consumption
continue to satisfy applicable provisions for sampling and testing.
At the 1998 workshop, DOE presented a basic model definition for
distribution transformers that incorporated these concepts. All groups
and individuals who participated in that workshop opposed DOE's
proposed definition because distribution transformers, unlike consumer
appliances, are not produced in large numbers of virtually identical
units. NEMA advocated at the workshop that DOE define basic model to
include all transformers having the same nominal power (kVA) rating,
the same insulation type (liquid immersed or dry-type), and the same
number of phases (single or three), and operating within the same
voltage range. (Public Workshop Tr., No. 2GG at pp. 54-55) \7\ The
Department proposed such a definition in the 1998 proposed rule. 63 FR
at 63369. As the Department pointed out in the 1999 reopening notice,
however, it later realized that this approach would allow a single
basic model to include models of transformers that have significantly
different utility or performance-related features that affect their
efficiency. This would be inconsistent with the nature of the groupings
that the ``basic model'' concept is meant to permit, since all models
within a basic model should be in the same product class. 64 FR at
33435.
---------------------------------------------------------------------------
\7\ ``Public Workshop Tr., No. 2GG at pp. 54-55'' refers to the
page number of the transcript of the ``Workshop on Test Procedures
for Distribution Transformers'' held in Washington, DC on February
10, 1998.
---------------------------------------------------------------------------
All of the comments to the 1999 reopening notice that addressed the
basic model definition supported the approach in the 1998 proposed
rule, but none addressed DOE's concern that the 1998 proposed rule
definition would permit inclusion of models with different energy
consumption characteristics in any particular basic model. One comment
stated that the proposed definition would be a sound way to reduce the
testing burden on manufacturers. (Howard Industries, No. 27 at p. 3)
DOE continues to believe that any definition of basic model under its
regulations must require that all of the models included in a basic
model have similar energy consumption characteristics and be within the
same product class. This is necessary to assure that the efficiency
rating derived for the basic model would accurately represent the
efficiency of all of these models. The Department is therefore
proposing a definition of basic model for distribution transformers
that includes essentially the same criteria contained in the definition
proposed in the 1998 proposed rule, plus a requirement that the
transformers included in the basic model ``not have any differentiating
electrical, physical or functional features that affect energy
consumption.''
Today's proposed definition includes two editorial modifications to
the criteria included in the 1998 proposed rule definition. First, the
proposed definition omits the provision that transformers within a
basic model must ``operate within the same voltage range.'' This
criterion need not be stated explicitly in the proposed definition
because it is embodied in the new proposed requirement that
transformers cannot have differentiating electrical features that
affect energy consumption. Second, the provision in the 1998 proposed
rule that all transformers in a basic model must ``have a comparable
nominal output power (kVA) rating'' is replaced in today's proposed
rule with language that they have ``the same standard KVA rating.'' Use
of the word ``same'' instead of ``comparable'' better achieves the
Department's intent in the 1998 proposed rule to require that all
transformers in a basic model have the same standard kVA rating, an
approach supported in comments on the 1998 proposed rule and 1999
reopening notice. (NEMA, No. 28 at p. 7; Howard Industries, No. 18 at
p. 3 and No. 27 at p. 3) In addition, the Department's understanding is
that ``standard kVA rating'' means the same thing as ``nominal output
power (kVA) rating.'' The former terminology is proposed here because
it is more succinct and straightforward.
Regarding the term ``standard kVA rating,'' the transformer
industry normally groups transformers based on apparent power rating
and over the years has developed a set of standard ratings, ANSI/IEEE
C57.12.00-2000 for liquid-immersed transformers and ANSI/IEEE
C57.12.01-1998 for dry-type transformers. These standard ratings are
set forth in the table that follows, and are the ratings that the
Department refers to when it uses the term ``standard kVA rating'' in
today's proposed basic model definition. Thus, under today's proposal,
grouping of distribution transformers into basic models would be based
in substantial part on groupings already used by the transformer
industry.
[[Page 45513]]
Standard kVA Ratings for Distribution Transformers*
[kVA]
------------------------------------------------------------------------
------------------------------------------------------------------------
Single phase
------------------------------------------------------------------------
10**............................................................ 167
15.............................................................. 250
25.............................................................. 333
37.5............................................................ 500
50.............................................................. 667
75.............................................................. 833
100............................................................. ......
-----------------------------------------------------------------
Three phase
------------------------------------------------------------------------
15.............................................................. 300
30.............................................................. 500
45.............................................................. 750
75.............................................................. 1000
112.5........................................................... 1500
150............................................................. 2000
225............................................................. 2500
------------------------------------------------------------------------
* The Department anticipates that it will subdivide the kVA ratings for
the medium-voltage dry-type distribution transformers by basic impulse
insulation level (BIL) rating during the standards rulemaking process,
and develop separate efficiency ratings for each BIL rating associated
with each kVA rating for these transformers. This would not affect
manufacturers' basic model delineations under today's proposed
definition of basic model. By providing that a basic model cannot
include transformers that have differentiating electrical features,
the proposed definition would already require that transformers with
different BIL ratings be separated into different basic models.
** 10 kVA is a standard rating for liquid-immersed distribution
transformers, but not necessarily for dry-type transformers.
The Department recognizes that any given manufacturer would likely
have more basic models under today's proposed definition of basic model
than under the 1998 proposed rule's definition. Potentially, this could
increase the manufacturers' test burden. The Department believes,
however, that this potential would be more than offset by its proposal,
discussed below, to allow manufacturers to determine the efficiencies
of a substantial number of their basic models by using alternative
efficiency determination methods, instead of testing these basic
models.
D. Manufacturer's Determination of Efficiency
In developing proposed requirements for distribution transformers,
the Department initially examined as a model its regulations for
consumer appliances in 10 CFR part 430, and later also examined its
regulations for electric motors in 10 CFR part 431, after it adopted
them in late 1999. Under both parts 430 and 431, each manufacturer must
determine the efficiency rating for each of its basic models, to a
substantial extent from testing the model. (Such testing is commonly
referred to as ``compliance testing.'') As just discussed, use of the
``basic model'' concept is one means for reducing the potential
compliance testing burden on manufacturers. The Department also reduces
the compliance testing burden by allowing manufacturers to test a
sample of units of each basic model. For each type of product, the
regulations prescribe a statistical sampling plan designed to give a
reasonable assurance that on average the performance of all units
manufactured and sold of each basic model complies with (i.e., equals
or exceeds) the manufacturer's rating for the model and the applicable
energy conservation standard mandated under EPCA.
In the 1998 proposed rule, the Department proposed to use part
430's sampling approach for compliance testing, with numerical criteria
geared to distribution transformers and a minimum sample size of five
units. 63 FR at 63366-67. But this approach is not well suited to
situations where only a very small test sample (fewer than five units,
for example) is available, and therefore it could be problematic for
some distribution transformers.\8\ Although some basic models of
transformers are mass-produced, many are custom-designed with
production runs of as few as one unit. Consequently, in the 1998
proposed rule the Department sought comment on three alternative
approaches for basic models with limited production. 63 FR at 63366-67.
---------------------------------------------------------------------------
\8\ The operating characteristics of the proposed compliance
plan were examined and reported in National Institute of Standards
and Technology (NIST) Technical Note (TN) 1427, ``An Analysis of
Efficiency Testing under the Energy Policy and Conservation Act: A
Case Study with Application to Distribution Transformers'' (NIST TN
1427). NIST TN 1427 noted for example that for a test sample of two
units of a basic model that is designed and performing at a given
rated value, and has a standard deviation of three percent, the
probability of demonstrating compliance with that rated value is
only about 0.12, and the probability of a false conclusion of
noncompliance is about 0.88.
---------------------------------------------------------------------------
In response to the 1998 proposed rule, industry representatives
commented that the proposed sampling plan might require manufacturers
to do a large amount of testing, and, as DOE had indicated in the 1998
proposed rule, the plan appears unsuitable for basic models with small
production volumes. (Public Meeting Tr., No. 11DD at p. 174; Howard
Industries, No. 18 at p.5) \9\ None of the comments, however, addressed
the alternatives DOE had presented for dealing with these small
production models. See 64 FR at 33434. NEMA advocated that DOE adopt
the sampling plan set forth in NEMA TP 2, significant elements of which
are (1) on-going testing during 180-day periods of either 100 percent
of the units manufactured or a random sample of a statistically valid
number of units (but not less than five per month), (2) discarding or
reworking all tested units that exceed losses allowed under the
applicable standard by more than eight percent,\10\ and (3) for each
180-day period, aggregating the test results of different basic models
(comprising all or a portion of a manufacturer's production) to
determine their collective compliance with the applicable standards.
---------------------------------------------------------------------------
\9\ ``Public Workshop Tr., No. 11DD at pp. 54-55'' refers to the
page number of the transcript of the ``Public Hearing on Energy
Efficiency Test Procedures--Distribution Transformers'' held in
Washington, DC on January 6, 1999.
\10\ For transformers, the industry practice is to measure power
loss and evaluate performance in terms of such losses. Performance
is expressed in terms of efficiency only at the final stage of
rating the product.
---------------------------------------------------------------------------
In the 1999 reopening notice, the Department expressed concern
about aggregation as used in NEMA TP 2, particularly for basic models
produced in relatively large volumes (50 or more in a six-month
period). In DOE's view, compliance of the large volume models could be
demonstrated without aggregation. But the Department stated that
aggregation combined with testing all of the units of a basic model has
some merit, particularly for limited production models. Therefore, DOE
identified for consideration several alternatives to the proposal in
the 1998 proposed rule, including variations on NEMA TP 2 that would
allow manufacturers to demonstrate the compliance of aggregations of
basic models subject to certain conditions. 64 FR at 33434-35. The goal
of these alternatives was to provide a reasonable statistical method
for deriving efficiency ratings from test results that would minimize
the risk of false negatives for small volume basic models, i.e., would
make it unlikely that a manufacturer would determine a complying basic
model to be out of compliance. The Department indicated, however, that
although some of these options may be sufficient to assure compliance
with efficiency standards by basic models that are included in
aggregations, they may not be adequate to establish the validity of the
represented efficiency level for particular basic models.
The comments on the 1999 reopening notice generally supported DOE's
adoption of the sampling plan in NEMA TP 2, with Howard Industries
urging DOE to adopt an approach that would minimize the number of units
that a manufacturer must test. (American Council for an Energy-
Efficient Economy, No. 29 at p. 3; Howard Industries, No. 27 at pp. 2-
3; NEMA, No. 28 at pp. 6-7). None of the comments, however, addressed
the
[[Page 45514]]
alternatives DOE had presented in the reopening notice that would allow
for aggregation of basic models. NEMA essentially reiterated its view
that the Department should adopt the sampling plan in NEMA TP 2, but
asserted in addition that the approach proposed in the 1998 proposed
rule had only a 50-percent probability of accurately representing the
mean efficiency level of all units of a basic model and was
statistically unsound. (NEMA, No. 28 at pp. 6-7)
Upon consideration of the comments in this proceeding, and a
further review of the sampling plan in NEMA TP 2, the Department
continues to believe that NEMA TP 2's sampling plan is inappropriate
for adoption as a DOE requirement. DOE has done considerable analysis
of this issue since issuing the 1998 proposed rule. The Department's
key concern regarding NEMA TP 2's sampling plan is the aggregation of
test results. NEMA TP 2 allows a manufacturer to aggregate the test
results of all or any portion of its basic models to determine their
compliance with applicable standards. (The NEMA TP 2 sampling plan
could also be used to determine compliance with rated efficiencies.)
All of the basic models included in an aggregate grouping would be
deemed to be in compliance (with applicable rated efficiencies and/or
standards) so long as their weighted average efficiency measured from
testing is equal to or larger than the weighted average rated
efficiency or standard that applies to them. Thus, in a group of basic
models found in compliance under NEMA TP 2's sampling plan, some of the
basic models could have efficiencies below their applicable levels so
long as other models exceed their levels. The Department recognizes
that NEMA TP 2's eight percent limitation on total losses for
individual tested units would encourage manufacturers to produce each
basic model at or above the applicable efficiency level, and would
provide some assurance that each basic model complies with that level.
However, given the variability inherent in the manufacture of
distribution transformers, the Department believes such assurance would
be of limited value.
This approach is unacceptable to DOE for several reasons. First,
the Department believes EPCA contemplates that each basic model of a
distribution transformer must comply with the efficiency standard
applicable to it, not that all or some other disparate grouping of
models will comply on average with the applicable standards. Section
346(a) of EPCA directs DOE to prescribe energy conservation standards
for those distribution transformers for which the Department determines
standards would save significant amounts of energy and would be
technologically feasible and economically justified. (42 U.S.C.
6317(a)) And section 346(f) in effect bars distribution of any
transformer that does not conform to the standard applicable to it. (42
U.S.C. 6317(f)) The Department believes these provisions preclude it
from mandating use of the sampling plan in NEMA TP 2, under which a
manufacturer could determine all or groups of its basic models to be in
compliance on average with applicable standards, with limited assurance
that any particular basic model complies.
Second, NEMA TP 2's sampling plan does not provide a sufficient
basis for a manufacturer to make representations as to the efficiency
of individual basic models. Section 346(d) of EPCA requires the
Department to prescribe efficiency labeling requirements for the
distribution transformers for which DOE prescribes standards. (42
U.S.C. 6317(d)) Although the statute does not specify the content of
such requirements, for other products the statute requires: (1)
Efficiency labels that are based on or include the energy efficiency of
the model on which the label appears, (see 42 U.S.C. 6293(b)(4),
6294(c), and 6315(d)-(e)) and (2) that any energy use or efficiency
representation by a manufacturer or other distributor ``fairly
discloses'' the results of testing the product under the DOE test
procedure (42 U.S.C. 6293(c) and 6314(d)). In addition, for consumer
products and electric motors, DOE requires manufacturers to certify to
the Department the efficiency or energy use of particular basic models
that are covered by energy conservation standards. 10 CFR 430.62 and
431.123. In 10 CFR 430.24 and 431.24, DOE provides the basis for
manufacturers to comply with these requirements, by prescribing
sampling plans and other methods for manufacturers to rate each basic
model they produce. As indicated above, however, because of the
aggregation of test results it contemplates, the sampling plan in NEMA
TP 2 could not be used to establish the efficiency of any particular
basic model. If the Department were to prescribe this sampling plan for
distribution transformers, it would in effect be precluded from
adopting for this product labeling and other energy representation
requirements based on the energy use or efficiency of particular basic
models, since no uniform basis would exist for assuring the accuracy of
such representations. This would represent a considerable departure
from the requirements for other products, and the Department believes
it would be inconsistent with the intent of EPCA's labeling
requirements.
Third, the NEMA TP 2 sampling provisions are problematic when one
considers the enforcement of efficiency standards and of labeling
requirements. On the one hand, in an enforcement action the Government
assesses whether a basic model is out of compliance with its labeled
efficiency or the applicable standard. NEMA TP 2 contemplates, however,
that a manufacturer could distribute a non-compliant basic model
provided the manufacturer included other ``overly compliant'' models in
an aggregation with the non-compliant model. The Department believes
this inconsistency in approaches is unacceptable. On the other hand, it
could be argued that DOE should align the enforcement provisions for
distribution transformers with NEMA TP 2's sampling plan. This would
mean that any enforcement action would have to concern all of the basic
models included in an aggregation that the manufacturer had used to
establish compliance, possibly including the manufacturer's entire line
of products. The Department strongly believes that such an approach
would be untenable, and that it should address its enforcement efforts
to individual basic models alleged to be out of compliance, not batches
of basic models.
Finally, NEMA TP 2 contemplates more compliance testing than either
part 430 or part 431. The sampling plan under part 430 prescribes no
minimum size for a test sample, and the minimum sample size under part
431 is five units. Under NEMA TP 2, a manufacturer must do continuous
testing either of 100 percent of the units it manufactures or of a
random sample of a statistically valid number of units (but not less
than five per month). Manufacturers are of course free to voluntarily
do any amount of testing they deem necessary to meet their own
contractual and other business requirements. DOE is reluctant, however,
to require this amount of testing, and to impose this burden as a legal
mandate.
For the foregoing reasons, the Department is not proposing to adopt
the sampling plan in NEMA TP 2. Nevertheless, the Department agrees
with NEMA that the sampling plan proposed in the 1998 proposed rule,
using a methodology similar to that in 10 CFR part 430, could impose a
significant risk of false negatives, i.e., compliant basic models found
to be non-compliant. The Department
[[Page 45515]]
recognizes that there are inherent differences between the products
regulated in part 430 and distribution transformers, and that these
differences warrant a sampling plan for distribution transformers that
is different from that in part 430. Manufacturers of electric motors
had similar concerns, and DOE adopted a new sampling plan for
determining a motor's efficiency in 10 CFR part 431.
DOE is proposing today to adopt both a sampling plan and
alternative methods (other than actual testing) for manufacturers to
use to determine the efficiency of distribution transformers, which are
similar to requirements that DOE has prescribed for electric motors.
Today's proposals are a substantial departure from the approaches
proposed in the 1998 proposed rule and 1999 reopening notice. The
Department believes they would require manufacturers to do
substantially less testing than contemplated either by the earlier
proposals or by NEMA TP 2, while at the same time ensuring that
products comply with applicable efficiency standards.
Today's proposed sampling plan is designed to have a significantly
higher probability than the 1998 proposed rule proposal that a basic
model would be found in compliance with its rated value where it is in
fact manufactured at that value, without incurring a probability for
significant false positives, i.e., non-complying models being found in
compliance. Similar to the sampling plan for motors, today's proposal
is predicated on the principle that the mean power loss of the sample
must be equal to or smaller than the rated loss plus five percent of
the rated loss divided by the square root of the number of units in the
sample. This translates into the ``Represented Efficiency'' expression
in today's proposed section 432.12. The tolerance of the motors plan is
constant, however, while that of today's proposed plan decreases with
increases in the sample size. The motors plan also has an additional
requirement that the power loss of a single unit in the sample must not
exceed the rated loss by more than 15 percent. Today's plan includes no
such provision in large part because the tolerance in today's proposal
decreases with increased sample size. The proposed plan provides the
same probability of demonstrating compliance for all sample sizes for a
basic model that is manufactured at the rated efficiency. Finally,
because the confidence limit varies with the standard deviation of the
population, under the proposed plan a very high probability exists that
complying basic models that have relatively small variabilities would
pass compliance testing, i.e., be found in compliance with their rated
values. For example, there is a 96.8 percent probability that a
complying basic model with a standard deviation of 2.7 percent would
pass compliance testing. Therefore, the manufacturer of such a basic
model could design and manufacture the product at very close to its
rated value, with little risk that it would fail compliance testing. A
more thorough analysis of today's proposed sampling plan is set forth
in NIST Technical Note 1456, ``Operating Characteristics of the
Proposed Sampling Plans for Testing Distribution Transformers,'' which
has been placed in the docket for this rulemaking and is publicly
available at http://www.eere.energy.gov/buildings/appliance_standards/commercial/dist_transformers.html
.
Today's proposed sampling plan also would limit the testing burden
on manufacturers. As with the motors plan, it prescribes a minimum test
sample size of five units except when fewer than that number of units
is manufactured in a 180-day period. It also handles samples as small
as one.
The key element that limits the test burden on manufacturers in
today's proposed rule, however, is the proposal to allow manufacturers
of distribution transformers to determine the efficiency of some of
their transformers through use of alternative efficiency determination
methods (AEDMs). An AEDM is a predictive mathematical model, developed
from engineering analyses of design data and substantiated by actual
test data, that represents the energy consumption characteristics of
one or more basic models. Under today's proposal, after it
substantiates the accuracy of an AEDM, the manufacturer can apply it to
basic models to determine their efficiencies without testing them. The
manufacturer would, however, have to determine the efficiency of at
least five of its basic models, selected in accordance with criteria
specified in the rule, through actual testing. The proposal would not
permit a manufacturer to use the AEDM to rate any model that it had
tested.
Today's proposal requires a manufacturer to substantiate an AEDM
based on actual testing of at least five basic models. (These could be
the same five basic models just referred to.) The manufacturer would
have to apply the AEDM to these basic models, and could use the AEDM to
determine the efficiency of other basic models only if, (1) the
predicted total power loss for each of these basic models, calculated
by applying the AEDM, is within five percent of the mean total power
loss determined from the testing of that basic model, and (2) the
average of the predicted total power loss for the tested basic models,
calculated by applying the AEDM, is within three percent of the average
of the total power loss determined from testing these basic models. In
making this second determination, the manufacturer would calculate the
average predicted power loss of each basic model as a percentage of the
average measured power loss, which in turn it would treat as 100
percent. This expression of power losses as percentages is necessary in
order for the manufacturer to assign equal weight to each basic model
used to substantiate the AEDM.
The Department selected the above tolerances because the power loss
predicted from an AEDM will differ from that predicted from testing
sample units of a basic model, due to the variability of units within
each model. The magnitude of such differences depends on the degree of
variability, quantified as the standard deviation, and the sample size.
As the number of units in each sample and the number of samples
increases the difference between the calculated and measured values
should decrease, but as a practical matter it never disappears. DOE
understands that a difference on the order of one to three percent is
the minimum that can be achieved. The maximum difference of plus or
minus three percent proposed in today's rule is appropriate for
populations consisting of at least five basic models with at least five
units in each. This allowable difference is equal to the allowable
measurement error in the test procedure specified in proposed section
432.11. The higher five-percent tolerance permitted for any single
basic model allows for situations where units of a basic model have
unusually high variability resulting in a relatively high standard
deviation of four percent. This can result from factors such as
variation in the materials used to produce the basic model and
variability in the manufacturing process. Such factors can affect an
entire production run for the basic model.
E. Enforcement Procedures
As it did in developing proposals for manufacturers to rate the
efficiency of distribution transformers, DOE reviewed the provisions of
10 CFR parts 430 and 431 in formulating proposed enforcement procedures
for this product. Parts 430 and 431 contain enforcement provisions that
apply when DOE examines whether a basic model of a covered product
complies with
[[Page 45516]]
efficiency requirements set forth in those parts. Each part allows for
enforcement testing where necessary, and each includes a sampling plan
for such testing. Neither the 1998 proposed rule nor the 1999 reopening
notice addressed enforcement. The Department believes, however, that it
is desirable to consider methods for manufacturers to use to rate their
distribution transformers, and methods for enforcement testing, in
conjunction with one another. Therefore, today's proposal includes
proposed enforcement procedures, including a sampling plan and other
provisions for enforcement testing. Substantial elements of these
procedures are drawn from part 431 and their application to
distribution transformers should not be controversial, but the
Department nevertheless welcomes comment on them. However, the
provisions as to the number of units to be tested and the number of
tests to be performed are not drawn from part 431, and the sampling
plan was developed specifically for application to distribution
transformers. These provisions reflect the fact that some basic models
of distribution transformers are produced in limited quantities. The
Department is particularly interested in receiving comments on these
provisions.
The proposed enforcement sampling plan establishes detailed
procedures for an enforcement action, and is similar to the enforcement
sampling plans established in parts 430 and 431. All of these plans are
based on a well established statistical method for obtaining a
confidence interval on a mean, which first originated in Charles Stein,
A Two-sample Test For a Linear Hypothesis Whose Power is Independent of
Variance, 16 Annals of Mathematical Statistics 243-258 (1945). This
procedure is discussed in Peter J. Bickel and Kjell A. Doksum,
Mathematical Statistics: Basic Ideas and Selected Topics 158-159
(1977), for example. The sampling plan for enforcement testing included
in part 430 covers both efficiency and energy consumption, and it is
general. The enforcement sampling plan proposed here, in Appendix B to
proposed part 432, has been adapted from part 430, but has been
simplified to address only efficiency testing. It also includes
provisions to allow tests of very small samples. These provisions
assure consistency with today's proposed sampling plan for compliance
testing, discussed above.
The proposed enforcement sampling plan is based on a t-test. The
Department believes that the t-test is well suited for use in
enforcement testing in that: (1) The t-test is insensitive to the exact
nature of the distribution of performance of the item being evaluated,
and (2) the risk of a false finding against a manufacturer can be set,
by design, to a negligible level.
The nature of the distribution of efficiency performance may be at
issue for some basic models of distribution transformers. Some of them
are produced in small quantities, and it is difficult to establish with
confidence an accurate distribution of efficiency performance for very
small test samples. Moreover, even some basic models produced in
relatively large quantities may not have a normally distributed
efficiency performance. Although the t-test assumes a normal
distribution, it is insensitive to departures from that assumption. The
t-test is a test on a sample mean that is an average of independent
values obtained from a random sample. Since sums of arbitrary,
independent random values tend to have a distribution that is almost
normal, i.e. is very close to normal, even if the values themselves are
not normally distributed, the t-test is not strongly influenced by the
exact form of the underlying distribution of these values (in this case
transformer efficiencies).
Under parts 430 and 431, the test results obtained during
enforcement testing may result in serious adverse actions against a
manufacturer. For example, the manufacturer must cease distribution and
sale of any basic model that the Department finds to be out of
compliance, and the Department can assess a civil penalty for such
noncompliance. Thus, the risk to a manufacturer of a false
determination of noncompliance during an enforcement action is set, by
design, to a negligible level. Today's proposed sampling plan for
enforcement is based on a 97.5 percent statistical confidence,
resulting in a risk of a false determination of noncompliance of not
greater than 2.5 percent.
As mentioned above, some basic models of distribution transformers
may have limited production, and thus, few units may be available for
testing. The proposed sampling plan for compliance testing contemplates
that a basic model would be in compliance with its rated efficiency so
long as the mean, measured efficiency of the compliance test sample of
the basic model meets the following test:
[GRAPHIC] [TIFF OMITTED] TP29JY04.034
where RE is the rated efficiency and n is the number of units tested.
Thus, the Department could find a basic model in compliance with its
rated efficiency even if the mean efficiency of the test sample is less
than the rated efficiency. This ``threshold efficiency'' establishes a
reasonable lower control limit for compliance testing when very few
units are available for testing.
Under the proposed plan for enforcement testing, DOE would test a
random sample and would calculate the mean, X, standard deviation, S,
standard error in the mean, SE(X), and a sample size discount, SSD(m).
In determining compliance with a rated efficiency, DOE would assume
that the tested units are drawn from a population of transformers for
which the mean efficiency is equal to or greater than the rated
efficiency. Using the value for t at the 97.5 percentile of the t-
distribution for n tests, that is for n-1 degrees of freedom, the
probability of obtaining a mean efficiency
[GRAPHIC] [TIFF OMITTED] TP29JY04.035
is not less than 97.5 percent. The procedure recommends a lower control
limit,
[GRAPHIC] [TIFF OMITTED] TP29JY04.036
where the sample size discount,
[GRAPHIC] [TIFF OMITTED] TP29JY04.037
is included to be consistent with the provisions, just discussed, of
the proposed plan for compliance testing. Here m is the number of units
available for testing, which may not exceed 20 and can range between 1
and 20 under the proposed provisions for enforcement testing. Provided
the mean efficiency obtained from the random sample is not less than
the lower control limit and the condition
[GRAPHIC] [TIFF OMITTED] TP29JY04.038
holds, the product is compliant.
In any statistical test there is some probability of a false
conclusion. Under the proposed sampling plan for enforcement, the
probability that the mean efficiency for a random sample drawn from a
compliant population of transformers would fall below the lower control
limit, and hence the risk of incorrectly concluding that the basic
model is in noncompliance, is not greater than 2.5 percent.
Furthermore, if both the proposed compliance and enforcement plans were
applied to the same sample test units, the risk of a false
determination of noncompliance with a represented efficiency under the
[[Page 45517]]
proposed enforcement testing plan is not greater than 2.5 percent for
units tested and found to be in compliance with that same represented
efficiency under the compliance testing plan. Finally, as in parts 430
and 431, today's proposed rule provides that after DOE determines a
basic model to be in noncompliance through testing under the
enforcement sampling plan, DOE will conduct additional testing if the
manufacturer so requests, and such testing could result in a
determination of compliance. This testing over and above that required
under the enforcement sampling plan would further reduce the likelihood
of a false determination of noncompliance and would thus allow a
manufacturer to reduce the risk of a false conclusion.
F. New Part 432
Section 346 of EPCA, 42 U.S.C. 6317, addresses energy conservation
requirements for distribution transformers, high-intensity discharge
lamps and small electric motors. As set forth in the 1998 proposed
rule, 63 FR at 63367, the Department is proposing to add a new Part 432
which would include efficiency regulations the Department adopts for
these products. In this notice, the Department is proposing to adopt,
and place in Part 432, regulations as to efficiency testing for
distribution transformers. At such time as the Department adopts energy
conservation standards and other requirements for distribution
transformers, or requirements for high-intensity discharge lamps or
small electric motors, it also intends to place them in Part 432.
III. Procedural Requirements
A. Review Under Executive Order 12866
The Office of Information and Regulatory Affairs of the Office of
Management and Budget (OMB) has determined that today's regulatory
action is not a ``significant regulatory action'' under Executive Order
12866, ``Regulatory Planning and Review,'' 58 FR 51735 (October 4,
1993). Accordingly, this action was not subject to review under the
Executive Order.
B. Review Under the Regulatory Flexibility Act
The Regulatory Flexibility Act (5 U.S.C. 601 et seq.) requires
preparation of an initial regulatory flexibility analysis for any rule
that by law must be proposed for public comment, unless the agency
certifies that the rule, if promulgated, will not have a significant
economic impact on a substantial number of small entities. As required
by Executive Order 13272, ``Proper Consideration of Small Entities in
Agency Rulemaking,'' 67 FR 53461 (August 16, 2002), DOE published
procedures and policies on February 19, 2003, to ensure that the
potential impacts of its rules on small entities are properly
considered during the rulemaking process (68 FR 7990). DOE has made its
procedures and policies available on the Office of General Counsel's
Web site: http://www.gc.doe.gov.
DOE reviewed today's rule under the provisions of the Regulatory
Flexibility Act and the procedures and policies published on February
19, 2003, and, for reasons that follow, certifies that the proposed
rule, if adopted as a final rule, will not impose a significant
economic impact on a substantial number of small entities.
In another rulemaking, the Department is in the early stages of
considering the adoption of mandatory energy conservation standards for
distribution transformers. Today's proposed rule would prescribe test
procedures that will be used to determine what standards, if any, DOE
would adopt in that rulemaking, and it also contains certain related
provisions. The proposed rule would likely become generally applicable
only upon adoption of standards. Unless and until DOE adopts such
standards, the Department anticipates that manufacturers will use the
test procedures to voluntarily test their transformers and provide to
DOE efficiency information about their products. But until energy
conservation standards are adopted, no entities, small or large, would
be required to comply with these test procedures, or with the other
parts of today's proposed rule. Therefore, DOE believes today's
proposed rule would not have a ``significant economic impact on a
substantial number of small entities,'' and the preparation of a
regulatory flexibility analysis is neither required nor warranted at
this point.
If the Department adopts standards for distribution transformers,
DOE's regulations would require manufacturers to produce transformers
that meet the standards. That requirement would have the effect of also
requiring manufacturers to comply with the provisions in today's
proposed rule (if it is subsequently adopted as a final rule), with
respect to the distribution transformers that are subject to the
standards. At that point, today's proposed rule would become binding
on, and could have an economic impact on, small entities. But the
nature and extent of any such impact cannot be assessed until the
Department develops standards. Until then, neither the identity nor the
proportion of distribution transformers covered by standards can be
known. Since today's proposed rule would only be mandatory as to
transformers covered by standards, only when that information is known
will it be possible to determine what if any burdens the proposed rule
would impose on small entities. In light of these circumstances, at an
appropriate point in conjunction with the standards rulemaking, the
Department will conduct further review under the Regulatory Flexibility
Act.
Accordingly, DOE has not prepared a regulatory flexibility analysis
for this rulemaking. DOE will transmit the certification and supporting
statement of factual basis to the Chief Counsel for Advocacy of the
Small Business Administration for review pursuant to 5 U.S.C. 605(b).
C. Review Under the Paperwork Reduction Act
Today's proposed rule contains certain record-keeping requirements.
For example, proposed Sec. 432.12(a)(4)(ii) would require
manufacturers to have records as to AEDMs available for DOE inspection,
and proposed Sec. 6.0 of Appendix A to Subpart B would require
maintenance of calibration records. But for the reasons explained in
Section III. B. above, unless and until the Department requires
manufacturers to comply with energy conservation standards for
distribution transformers, no manufacturer would be required to comply
with these record-keeping provisions. Therefore, today's notice of
proposed rulemaking would not impose any new reporting requirements
requiring clearance by OMB under the Paperwork Reduction Act, 44 U.S.C.
3501 et seq.
The Department recognizes, however, that if it adopts standards for
distribution transformers, once the standards become operative
manufacturers will become subject to the record-keeping requirements in
today's proposed rule (if it has been adopted in a final rule). Prior
to that time, therefore, these requirements, if covered by the
Paperwork Reduction Act, must be reviewed and approved by OMB. In
addition, in conjunction with proposing any standards for transformers,
the Department may propose additional reporting and/or record-keeping
requirements for this product that are similar to requirements already
in place for consumer products in 10 CFR 430.62 and for electric motors
in 10 CFR 431.123 and 431.124. Any such additional requirements also
may be subject to clearance under the
[[Page 45518]]
Paperwork Reduction Act. The Department anticipates a Paperwork
Reduction Act submission that will cover any such additional
requirements and the information collection requirements in today's
proposed rule.
For these reasons, the Department will comply with the Paperwork
Reduction Act with respect to the record-keeping requirements in
today's rule at the appropriate point in conjunction with the standards
development rulemaking. DOE nonetheless invites public comment on the
collections of information proposed today.
D. Review Under the National Environmental Policy Act
In this rulemaking, DOE proposes to adopt test procedures and
related provisions for distribution transformers. The test procedures
would be used initially for the purpose of considering the adoption of
energy conservation standards for transformers, and DOE would require
their use only if standards are subsequently adopted. The proposed test
procedures will not affect the quality or distribution of energy and,
therefore, will not result in any environmental impacts. DOE,
therefore, determined that this rule falls into a class of actions that
are categorically excluded from review under the National Environmental
Policy Act of 1969 (42 U.S.C. 4321 et seq.) and the Department's
implementing regulations at 10 CFR part 1021. More specifically,
today's rule is covered by the Categorical Exclusion in paragraph A6 to
subpart D, 10 CFR part 1021. Accordingly, neither an environmental
assessment nor an environmental impact statement is required.
E. Review Under Executive Order 13132
Executive Order 13132, ``Federalism,'' 64 FR 43255 (August 4, 1999)
imposes certain requirements on agencies formulating and implementing
policies or regulations that preempt State law or that have federalism
implications. The Executive Order requires agencies to examine the
constitutional and statutory authority supporting any action that would
limit the policymaking discretion of the States and carefully assess
the necessity for such actions. The Executive Order also requires
agencies to have an accountable process to ensure meaningful and timely
input by State and local officials in the development of regulatory
policies that have federalism implications. On March 14, 2000, DOE
published a statement of policy describing the intergovernmental
consultation process it will follow in the development of such
regulations (65 FR 13735). DOE has examined today's proposed rule and
has determined that it does not preempt State law and does not have a
substantial direct effect on the States, on the relationship between
the national government and the States, or on the distribution of power
and responsibilities among the various levels of government. No further
action is required by Executive Order 13132.
F. Review Under Executive Order 12988
With respect to the review of existing regulations and the
promulgation of new regulations, section 3(a) of Executive Order 12988,
``Civil Justice Reform'' (61 FR 4729, February 7, 1996), imposes on
Federal agencies the general duty to adhere to the following
requirements: (1) Eliminate drafting errors and ambiguity; (2) write
regulations to minimize litigation; and (3) provide a clear legal
standard for affected conduct rather than a general standard and
promote simplification and burden reduction. Section 3(b) of Executive
Order 12988 specifically requires that Executive agencies make every
reasonable effort to ensure that the regulation: (1) Clearly specifies
the preemptive effect, if any; (2) clearly specifies any effect on
existing Federal law or regulation; (3) provides a clear legal standard
for affected conduct while promoting simplification and burden
reduction; (4) specifies the retroactive effect, if any; (5) adequately
defines key terms; and (6) addresses other important issues affecting
clarity and general draftsmanship under any guidelines issued by the
Attorney General. Section 3(c) of Executive Order 12988 requires
Executive agencies to review regulations in light of applicable
standards in section 3(a) and section 3(b) to determine whether they
are met or it is unreasonable to meet one or more of them. DOE has
completed the required review and determined that, to the extent
permitted by law, this proposed rule meets the relevant standards of
Executive Order 12988.
G. Review Under the Unfunded Mandates Reform Act of 1995
Title II of the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-
4) (UMRA) requires each Federal agency to assess the effects of Federal
regulatory actions on State, local, and tribal governments and the
private sector. With respect to a proposed regulatory action that may
result in the expenditure by State, local and tribal governments, in
the aggregate, or by the private sector of $100 million or more
(adjusted annually for inflation), section 202 of UMRA requires a
Federal agency to publish estimates of the resulting costs, benefits,
and other effects on the national economy. (2 U.S.C. 1532(a), (b)) UMRA
also requires a Federal agency to develop an effective process to
permit timely input by elected officers of State, local, and tribal
governments on a proposed ``significant intergovernmental mandate,''
and requires an agency plan for giving notice and opportunity for
timely input to potentially affected small governments before
establishing any requirements that might significantly or uniquely
affect small governments. On March 18, 1997, DOE published a statement
of policy on its process for intergovernmental consultation under UMRA
(62 FR 12820) (also available at http://www.gc.doe.gov). The proposed
rule published today does not provide for any Federal mandate likely to
result in an aggregate expenditure of $100 million or more. Therefore,
the UMRA does not require a cost benefit analysis of today's proposal.
H. Review Under the Treasury and General Government Appropriations Act,
1999
Section 654 of the Treasury and General Government Appropriations
Act, 1999 (Pub. L. 105-277) requires Federal agencies to issue a Family
Policymaking Assessment for any rule that may affect family well-being.
This proposed rule would not have any impact on the autonomy or
integrity of the family as an institution. Accordingly, DOE has
concluded that it is not necessary to prepare a Family Policymaking
Assessment.
I. Review Under Executive Order 12630
DOE has determined pursuant to Executive Order 12630,
``Governmental Actions and Interference with Constitutionally Protected
Property Rights,'' 53 FR 8859 (March 18, 1988) that this proposed rule
would not result in any takings which might require compensation under
the Fifth Amendment to the United States Constitution.
J. Review Under the Treasury and General Government Appropriations Act,
2001
The Treasury and General Government Appropriations Act, 2001 (44
U.S.C. 3516, note) provides for agencies to review most disseminations
of information to the public under guidelines established by each
agency pursuant to general guidelines issued by OMB. OMB's guidelines
were published at 67 FR 8452 (February 22, 2002), and DOE's guidelines
were published at 67 FR 62446 (October 7, 2002). DOE has
[[Page 45519]]
reviewed today's notice under the OMB and DOE guidelines and has
concluded that it is consistent with applicable policies in those
guidelines.
K. Review Under Executive Order 13211
Executive Order 13211, ``Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use,'' 66 FR 28355
(May 22, 2001) requires Federal agencies to prepare and submit to the
Office of Information and Regulatory Affairs (OIRA), Office of
Management and Budget, a Statement of Energy Effects for any proposed
significant energy action. A ``significant energy action'' is defined
as any action by an agency that promulgated or is expected to lead to
promulgation of a final rule, and that: (1) Is a significant regulatory
action under Executive Order 12866, or any successor order; and (2) is
likely to have a significant adverse effect on the supply,
distribution, or use of energy, or (3) is designated by the
Administrator of OIRA as a significant energy action. For any proposed
significant energy action, the agency must give a detailed statement of
any adverse effects on energy supply, distribution, or use should the
proposal be implemented, and of reasonable alternatives to the action
and their expected benefits on energy supply, distribution, and use.
Today's regulatory action is not a significant regulatory action under
Executive Order 12866. Moreover, it would not have a significant
adverse effect on the supply, distribution, or use of energy.
Therefore, it is not a significant energy action, and DOE has not
prepared a Statement of Energy Effects.
L. Review Under Section 32 of the Federal Energy Administration Act of
1974
Under section 301 of the Department of Energy Organization Act
(Pub. L. 95-91), the Department of Energy must comply with section 32
of the Federal Energy Administration Act of 1974, as amended by the
Federal Energy Administration Authorization Act of 1977. (15 U.S.C.
788) Section 32 provides in part that, where a proposed rule contains
or involves use of commercial standards, the rulemaking must inform the
public of the use and background of such standards.
The rule proposed in this notice incorporates testing methods
contained in the following commercial standards: (1) IEEE Standard
C57.12.90-1999, ``IEEE Standard Test Code for Liquid-Immersed
Distribution, Power and Regulating Transformers and IEEE Guide for
Short Circuit Testing of Distribution and Power Transformers,'' (2)
IEEE Standard C57.12.91-2001, ``IEEE Standard Test Code for Dry-Type
Distribution and Power Transformers,'' (3) IEEE Standard C57.12.00-
2000, ``IEEE Standard General Requirements for Liquid-Immersed
Distribution, Power and Regulating Transformers,'' (4) IEEE Standard
C57.12.01-1998, ``IEEE Standard General Requirements for Dry-Type
Distribution and Power Transformers Including those with Solid Cast
and/or Resin Encapsulated Windings,'' and (5) NEMA Standards
Publication No. TP 2-1998, ``Standard Test Method for Measuring the
Energy Consumption of Distribution Transformers.'' The Department has
evaluated these standards and is unable to conclude whether they fully
comply with the requirements of section 32(b) of the Federal Energy
Administration Act, i.e., they were developed in a manner that fully
provides for public participation, comment and review.
As required by section 32(c) of the Federal Energy Administration
Act, of 1974, as amended, DOE will consult with the Attorney General
and the Chairman of the Federal Trade Commission, prior to prescribing
a final rule, concerning the impact on competition of requiring use of
methods contained in these standards to test distribution transformers.
IV. Public Participation
A. Attendance at Public Meeting
The time and date of the public meeting are listed in the DATES
section at the beginning of this notice of proposed rulemaking. The
public meeting will be held at the U.S. Department of Energy, Forrestal
Building, Room 1E-245, 1000 Independence Avenue, SW., Washington, DC,
20585. To attend the public meeting, please notify Ms. Brenda Edwards-
Jones at (202) 586-2945. Foreign nationals visiting DOE Headquarters
are subject to advance security screening procedures, requiring a 30-
day advance notice. Any foreign national wishing to participate in the
meeting should advise DOE of this fact as soon as possible by
contacting Ms. Brenda Edwards-Jones to initiate the necessary
procedures.
B. Procedure for Submitting Requests To Speak
Any person who has an interest in today's notice, or who is a
representative of a group or class of persons that has an interest in
these issues, may request an opportunity to make an oral presentation.
Such persons may hand-deliver requests to speak, along with a computer
diskette or CD in WordPerfect, Microsoft Word, PDF, or text (ASCII)
file format to the address shown in the ADDRESSES section at the
beginning of this supplemental notice of proposed rulemaking between
the hours of 9 a.m. and 4 p.m., Monday through Friday, except Federal
holidays. Requests may also be sent by mail or e-mail to:
Persons requesting to speak should briefly describe the nature of
their interest in this rulemaking and provide a telephone number for
contact. The Department requests persons selected to be heard to submit
an advance copy of their statements at least two weeks before the
public meeting. At its discretion, DOE may permit any person who cannot
supply an advance copy of their statement to participate, if that
person has made advance alternative arrangements with the Building
Technologies Program. The request to give an oral presentation should
ask for such alternative arrangements.
C. Conduct of Public Meeting
The Department will designate a DOE official to preside at the
public meeting and may also use a professional facilitator to aid
discussion. The meeting will not be a judicial or evidentiary-type
public hearing, but DOE will conduct it in accordance with 5 U.S.C. 553
and section 336 of EPCA. A court reporter will be present to record the
proceedings and prepare a transcript. The Department reserves the right
to schedule the order of presentations and to establish the procedures
governing the conduct of the public meeting. After the public meeting,
interested parties may submit further comments on the proceedings as
well as on any aspect of the rulemaking until the end of the comment
period.
The public meeting will be conducted in an informal, conference
style. The Department will present summaries of comments received
before the public meeting, allow time for presentations by
participants, and encourage all interested parties to share their views
on issues affecting this rulemaking. Each participant will be allowed
to make a prepared general statement (within time limits determined by
DOE), before the discussion of specific topics. The Department will
permit other participants to comment briefly on any general statements.
At the end of all prepared statements on a topic, DOE will permit
participants to clarify their statements briefly and comment on
statements made by others. Participants should be prepared to answer
questions by DOE and by other
[[Page 45520]]
participants concerning these issues. Department representatives may
also ask questions of participants concerning other matters relevant to
this rulemaking. The official conducting the public meeting will accept
additional comments or questions from those attending, as time permits.
The presiding official will announce any further procedural rules or
modification of the above procedures that may be needed for the proper
conduct of the public meeting.
The Department will make the entire record of this proposed
rulemaking, including the transcript from the public meeting, available
for inspection at the U.S. Department of Energy, Forrestal Building,
Room 1J-018 (Resource Room of the Building Technologies Program), 1000
Independence Avenue, SW., Washington, DC 20585, (202) 586-9127, between
9 a.m. and 4 p.m., Monday through Friday, except Federal holidays. Any
person may buy a copy of the transcript of the public hearing
proceedings from the transcribing reporter.
D. Submission of Comments
The Department will accept comments, data, and information
regarding the proposed rule before or after the public meeting, but no
later than the date provided at the beginning of this notice of
proposed rulemaking. Please submit comments, data, and information
electronically. Send them to the following e-mail address:
DistTransformersTP-SNOPR@ee.doe.gov. Submit electronic comments in
WordPerfect, Microsoft Word, PDF, or text (ASCII) file format and avoid
the use of special characters or any form of encryption. Comments in
electronic format should be identified by the docket number EE-TP-98-
550 and/or RIN number, and wherever possible carry the electronic
signature of the author. Absent an electronic signature, comments
submitted electronically must be followed and authenticated by
submitting the signed original paper document. No telefacsimiles
(faxes) will be accepted.
According to 10 CFR 1004.11, any person submitting information that
he or she believes to be confidential and exempt by law from public
disclosure should submit two copies: one copy of the document including
all the information believed to be confidential, and one copy of the
document with the information believed to be confidential deleted. The
Department of Energy will make its own determination about the
confidential status of the information and treat it according to its
determination.
Factors of interest to the Department when evaluating requests to
treat submitted information as confidential include: (1) A description
of the items; (2) whether and why such items are customarily treated as
confidential within the industry; (3) whether the information is
generally known by or available from other sources; (4) whether the
information has previously been made available to others without
obligation concerning its confidentiality; (5) an explanation of the
competitive injury to the submitting person which would result from
public disclosure; (6) when such information might lose its
confidential character due to the passage of time; and (7) why
disclosure of the information would be contrary to the public interest.
List of Subjects in 10 CFR Part 432
Administrative practice and procedure, Energy conservation,
Distribution transformers.
The Secretary of Energy has approved publication of today's rule.
Issued in Washington, DC on May 26, 2004.
David K. Garman,
Assistant Secretary, Energy Efficiency and Renewable Energy.
For the reasons set forth in the preamble, Chapter II of Title 10,
Code of Federal Regulations, is proposed to be amended by adding a new
Part 432 to read as set forth below.
PART 432--ENERGY CONSERVATION PROGRAM FOR DISTRIBUTION TRANSFORMERS
Subpart A--General Provisions
Sec.
432.1 Purpose and scope.
432.2 Definitions.
Subpart B--Distribution Transformers
432.10 Definitions.
432.11 Test procedures for measuring energy consumption of
distribution transformers.
432.12 Manufacturer's determination of efficiency for distribution
transformers.
432.13 Enforcement testing for distribution transformers.
Appendix A to Subpart B of Part 432--Uniform Test Method for
Measuring the Energy Consumption of Distribution Transformers
Appendix B to Subpart B of Part 432--Sampling Plan for Enforcement
Testing
Subpart C--[Reserved]
Subpart D--[Reserved]
Authority: 42 U.S.C. 6317.
Subpart A--General Provisions
Sec. 432.1 Purpose and scope.
This part contains energy conservation requirements that the
Department has promulgated pursuant to section 346 of EPCA, 42 U.S.C.
6317.
Sec. 432.2 Definitions.
The following definitions apply for purposes of this part:
Act means the Energy Policy and Conservation Act of 1975, as
amended, 42 U.S.C. 6291-6317.
DOE or the Department means the Department of Energy.
EPCA means the Energy Policy and Conservation Act of 1975, as
amended, 42 U.S.C. 6291-6317.
Secretary means the Secretary of the Department of Energy.
Subpart B--Distribution Transformers
Sec. 432.10 Definitions.
The following definitions apply for purposes of this subpart:
Autotransformer means a transformer that:
(1) Has one physical winding that consists of a series winding part
and a common winding part;
(2) Has no isolation between its primary and secondary circuits;
and
(3) During step-down operation, has a primary voltage that is equal
to the total of the series and common winding voltages, and a secondary
voltage that is equal to the common winding voltage.
Basic model means a group of distribution transformers manufactured
by a single manufacturer, that have the same insulation type (i.e.,
liquid-immersed or dry-type), have the same number of phases (i.e.,
single or three), have the same standard kVA rating, and do not have
any differentiating electrical, physical or functional features that
affect energy consumption.
Distribution transformer means a transformer with a primary voltage
of equal to or less than 35 kV, a secondary voltage equal to or less
than 600 V, a frequency of 55-65 Hz, and a capacity of 10 kVA to 2500
kVA for liquid-immersed units and 15 kVA to 2500 kVA for dry-type
units, and does not include the following types of transformers:
(1) Autotransformer;
(2) Drive (isolation) transformer;
(3) Grounding transformer;
(4) Harmonic mitigating transformer;
(5) K-Factor Transformer;
(6) Machine-Tool (Control) Transformer;
(7) Non-ventilated Transformer;
(8) Rectifier Transformer;
(9) Regulating Transformer;
[[Page 45521]]
(10) Sealed Transformer;
(11) Special-Impedance Transformer;
(12) Testing Transformer;
(13) Transformer with Tap Range greater than 15 percent;
(14) Uninterruptible Power Supply Transformer; or
(15) Welding Transformer.
Drive (isolation) transformer means a transformer that:
(1) Isolates an electric motor from the line;
(2) Accommodates the added loads of drive-created harmonics; and
(3) Is designed to withstand the additional mechanical stresses
resulting from an alternating current adjustable frequency motor drive
or a direct current motor drive.
Dry-type distribution transformer means a distribution transformer
in which the core and coil assembly is immersed in a gaseous or dry-
compound insulating medium.
Efficiency means the ratio of the useful power output to the total
power input.
Excitation current or no-load current means the current that flows
in any winding used to excite the transformer when all other windings
are open-circuited.
Grounding transformer means a three-phase transformer intended
primarily to provide a neutral point for system-grounding purposes,
either by means of:
(1) A grounded wye primary winding and a delta secondary winding;
or
(2) An autotransformer with a zig-zag winding arrangement.
Harmonic mitigating transformer means a transformer designed to
cancel or reduce the harmonics drawn by computer equipment and other
non-linear power electronic loads.
K-Factor transformer means a transformer with a K-Factor of 13 or
greater that is designed to tolerate the additional eddy-current losses
resulting from harmonics drawn by non-linear loads, usually when the
ratio of the non-linear load to the linear load is greater than 50
percent.
Liquid-immersed distribution transformer means a distribution
transformer in which the core and coil assembly is immersed in an
insulating liquid.
Load loss means, for a distribution transformer, those losses
incident to a specified load carried by the transformer, including
losses in the windings as well as stray losses in the conducting parts
of the transformer. It does not include no-load losses.
Low-voltage distribution transformer means a dry-type distribution
transformer with a rated primary voltage of 600 V or less.
Machine-tool (control) transformer means a transformer that is
equipped with a fuse or other over current protection device, and is
generally used for the operation of a solenoid, contactor, relay,
portable tool, or localized lighting.
Medium-voltage distribution transformer means a dry-type
distribution transformer with rated primary voltage between 601 V and
35 kV.
No-load loss means those losses that are incident to the excitation
of the transformer.
Non-ventilated transformer means a transformer constructed so as to
prevent external air circulation through the coils of the transformer
while operating at zero gauge pressure.
Phase angle means the angle between two phasors, where the two
phasors represent progressions of periodic waves of either:
(1) Two voltages;
(2) Two currents; or
(3) A voltage and a current of an alternating current circuit.
Phase angle correction means the adjustment (correction) of
measurement data to negate the effects of phase angle error.
Phase angle error means incorrect displacement of the phase angle,
introduced by the components of the test equipment.
Rectifier transformer means a transformer that operates at the
fundamental frequency of an alternating-current system and that is
designed to have one or more output windings connected to a rectifier.
Reference temperature means 20 [deg]C for no-load loss, 55 [deg]C
for liquid-immersed distribution transformers at 50% load, and 75
[deg]C for both low-voltage and medium-voltage dry-type distribution
transformers, at 35% load and 50% load, respectively. It is the
temperature at which the transformer losses must be determined, and to
which such losses must be corrected if testing is done at a different
point. (These temperatures are specified in the test method in Appendix
A to this part.)
Regulating Transformer means a transformer that varies the voltage,
the phase angle, or both voltage and phase angle, of an output circuit
and compensates for fluctuation of load and input voltage, phase angle
or both voltage and phase angle.
Sealed Transformer means a transformer designed to remain
hermetically sealed under specified conditions of temperature and
pressure.
Special-Impedance Transformer means any transformer built to
operate at an impedance outside of the normal impedance range for that
transformer's kVA rating. The normal impedance range for each kVA
rating for liquid-immersed and dry-type transformers is shown in Tables
1 and 2, respectively.
Table 1.--Normal Impedance Ranges for Liquid-Immersed Transformers
----------------------------------------------------------------------------------------------------------------
Single-phase transformers Three-phase transformers
----------------------------------------------------------------------------------------------------------------
kVA Impedance (%) kVA Impedance (%)
----------------------------------------------------------------------------------------------------------------
10 1.0-4.5 15 1.0-4.5
15 1.0-4.5 30 1.0-4.5
25 1.0-4.5 45 1.0-4.5
37.5 1.0-4.5 75 1.0-5.0
50 1.5-4.5 112.5 1.2-6.0
75 1.5-4.5 150 1.2-6.0
100 1.5-4.5 225 1.2-6.0
167 1.5-4.5 300 1.2-6.0
250 1.5-6.0 500 1.5-7.0
333 1.5-6.0 750 5.0-7.5
500 1.5-7.0 1000 5.0-7.5
667 5.0-7.5 1500 5.0-7.5
833 5.0-7.5 2000 5.0-7.5
2500 5.0-7.5
----------------------------------------------------------------------------------------------------------------
[[Page 45522]]
Table 2.--Normal Impedance Ranges for Dry-Type Transformers
----------------------------------------------------------------------------------------------------------------
Single-phase transformers Three-phase transformers
----------------------------------------------------------------------------------------------------------------
kVA Impedance (%) kVA Impedance (%)
----------------------------------------------------------------------------------------------------------------
15 1.5-6.0 15 1.5-6.0
25 1.5-6.0 30 1.5-6.0
37.5 1.5-6.0 45 1.5-6.0
50 1.5-6.0 75 1.5-6.0
75 2.0-7.0 112.5 1.5-6.0
100 2.0-7.0 150 1.5-6.0
167 2.5-8.0 225 3.0-7.0
250 3.5-8.0 300 3.0-7.0
333 3.5-8.0 500 4.5-8.0
500 3.5-8.0 750 5.0-8.0
667 5.0-8.0 1000 5.0-8.0
833 5.0-8.0 1500 5.0-8.0
2000 5.0-8.0
2500 5.0-8.0
----------------------------------------------------------------------------------------------------------------
Temperature Correction means the mathematical correction(s) of
measurement data, obtained when a transformer is tested at a
temperature that is different from the reference temperature, to the
value(s) that would have been obtained if the transformer had been
tested at the reference temperature.
Test Current means the current of the electrical power supplied to
the transformer under test.
Test Frequency means the frequency of the electrical power supplied
to the transformer under test.
Test Voltage means the voltage of the electrical power supplied to
the transformer under test.
Testing Transformer means a transformer used in a circuit to
produce a specific voltage or current for the purpose of testing
electrical equipment. This type of transformer is also commonly known
as an Instrument Transformer.
Total Loss means the sum of the no-load loss and the load loss for
a transformer.
Transformer means a static electric device consisting of a winding
or two or more coupled windings, with a magnetic core, for introducing
mutual coupling between electric circuits.
Transformer with Tap Range greater than 15 percent means a
transformer with a tap range in the primary winding greater than the
range accomplished with six, 2.5-percent taps, 3 above and 3 below the
rated primary voltage (e.g., 6 times 2.5 percent = 15 percent).
Uninterruptible Power Supply Transformer means a transformer that
supplies power to an uninterruptible power system, which in turn
supplies power to loads that are sensitive to power failure, power
sags, over voltage, switching transients, line noise, and other power
quality factors.
Waveform Correction means the adjustment(s) (mathematical
correction(s)) of measurement data obtained with a test voltage that is
non-sinusoidal, to a value(s) that would have been obtained with a
sinusoidal voltage.
Welding Transformer means a transformer designed for use in arc
welding equipment or resistance welding equipment.
Sec. 432.11 Test procedures for measuring energy consumption of
distribution transformers.
The test procedures for measuring the energy efficiency of
distribution transformers for purposes of EPCA are specified in
Appendix A to this subpart (``Appendix A'').
Sec. 432.12 Manufacturer's determination of efficiency for
distribution transformers.
When a manufacturer or other party (both of which this section
refers to as a ``manufacturer'') determines the efficiency of a
distribution transformer in order to comply with an obligation imposed
on it by or pursuant to Part C of Title III of EPCA, 42 U.S.C. 6311-
6317, this section applies. This section does not apply to enforcement
testing conducted pursuant to Sec. 432.13 of this part.
(a) Methods used to determine efficiency.
(1) General Requirements. A manufacturer must determine the
efficiency of each basic model of distribution transformer either by
testing in accordance with Sec. 432.11 of this part and paragraph
(b)(2) of this section, or by application of an alternative efficiency
determination method (AEDM) that meets the requirements of paragraphs
(a)(2) and (a)(3) of this section; provided, however, that a
manufacturer may use an AEDM to determine the efficiency of one or more
of its untested basic models only if it determines the efficiency of at
least five of its other basic models (selected in accordance with
paragraph (b)(1) of this section) through actual testing.
(2) Alternative efficiency determination method. A manufacturer may
apply an AEDM to a basic model only if:
(i) The AEDM has been derived from a mathematical model that
represents the electrical characteristics of that basic model;
(ii) The AEDM is based on engineering and statistical analysis,
computer simulation or modeling, or other analytic evaluation of
performance data; and
(iii) In applying the AEDM to distribution transformers, the
manufacturer uses the AEDM only for one or more of its basic models in
one of the following groups of distribution transformers: low-voltage
dry-type transformers, medium-voltage dry-type transformers, and
liquid-immersed transformers.
(3) Substantiation of an alternative efficiency determination
method. Before using an AEDM, the manufacturer must substantiate the
AEDM's accuracy and reliability as follows:
(i) Apply the AEDM to at least five of the manufacturer's basic
models that have been selected for testing in accordance with paragraph
(b)(1) of this section, and calculate the power loss for each of these
basic models;
(ii) Test at least five units of each of these basic models in
accordance with the applicable test procedure and paragraph (b)(2) of
this section, and determine the power loss for each of these basic
models;
(iii) The predicted total power loss for each of these basic
models, calculated by applying the AEDM pursuant to paragraph (a)(3)(i)
of this section, must be within plus or minus five percent of
[[Page 45523]]
the mean total power loss determined from the testing of that basic
model pursuant to paragraph (a)(3)(ii) of this section; and
(iv) Calculate for each of these basic models the percentage that
its power loss calculated pursuant to paragraph (a)(3)(i) is of its
power loss determined from testing pursuant to paragraph (a)(3)(ii),
compute the average of these percentages, and that calculated average
power loss, expressed as a percentage of the average power loss
determined from testing, must be no less than 97 percent and no greater
than 103 percent.
(4) Subsequent verification of an AEDM.
(i) Each manufacturer shall periodically select basic models
representative of those to which it has applied an AEDM, and for each
basic model selected shall either:
(A) Subject a sample of at least five units to testing in
accordance with the applicable test procedure and paragraph (b)(2) of
this section by an independent testing laboratory; or
(B) Have an independent state-registered professional engineer, who
is qualified to perform an evaluation of distribution transformer
efficiency in a highly competent manner and who is not an employee of
the manufacturer, review the manufacturer's representations and certify
that the results of the AEDM accurately represent the total power loss
and efficiency of the basic model.
(ii) Each manufacturer that has used an AEDM under this section
shall have available for inspection by the Department of Energy records
showing: the method or methods used; the mathematical model, the
engineering or statistical analysis, computer simulation or modeling,
and other analytic evaluation of performance data on which the AEDM is
based; complete test data, product information, and related information
that the manufacturer has generated or acquired pursuant to paragraphs
(a)(3) and (a)(4)(i) of this section; and the calculations used to
determine the efficiency and total power losses of each basic model to
which the AEDM was applied.
(iii) If requested by the Department, the manufacturer shall
conduct simulations to predict the performance of particular basic
models of distribution transformers specified by the Department,
analyses of previous simulations conducted by the manufacturer, sample
testing of basic models selected by the Department, or a combination of
the foregoing.
(b) Additional testing requirements.
(1) Selection of basic models for testing if an AEDM is to be
applied.
(i) A manufacturer must select basic models for testing in
accordance with the following criteria:
(A) Two of the basic models must be among the five basic models
with the highest unit volumes of production by the manufacturer in the
prior year, or during the prior 12-calendar-month period beginning in
2003,\1\ whichever is later;
---------------------------------------------------------------------------
\1\ When identifying these five basic models, any basic model
that does not comply with Federal energy conservation standards for
distribution transformers that may be in effect shall be excluded
from consideration.
---------------------------------------------------------------------------
(B) No two basic models should have the same combination of power
and voltage ratings; and
(C) At least one basic model should be single-phase and at least
one should be three-phase.
(ii) In any instance where it is impossible for a manufacturer to
select basic models for testing in accordance with all of these
criteria, the criteria shall be given priority in the order in which
they are listed. Within the limits imposed by the criteria, basic
models shall be selected randomly.
(2) Selection of units for testing within a basic model. For each
basic model a manufacturer selects for testing, it shall select a
sample of units at random and test them. The sample shall be comprised
of production units of the basic model, or units that are
representative of such production units. The sample size shall be not
fewer than five units, except that when the manufacturer would produce
fewer than five units of a basic model over a reasonable period of time
(approximately 180 days), then it must test each unit. However, a
manufacturer may not use a basic model with a sample size of fewer than
five units to substantiate or verify an AEDM pursuant to paragraphs
(a)(3) or (a)(4) of this section. In a test of compliance with a
represented efficiency:
The average efficiency of the sample, X, which is defined by
[GRAPHIC] [TIFF OMITTED] TP29JY04.000
where Xi is the measured efficiency of unit i and n is the
number of units tested, must satisfy the condition:
[GRAPHIC] [TIFF OMITTED] TP29JY04.001
where RE is the represented efficiency.
Sec. 432.13 Enforcement testing for distribution transformers.
(a) Test notice. Upon receiving information in writing, concerning
the energy performance of a particular distribution transformer sold by
a particular manufacturer or private labeler, which indicates that the
transformer may not be in compliance with the applicable energy
efficiency standard, or upon undertaking to ascertain the accuracy of
the efficiency rating on the nameplate or in marketing materials for a
distribution transformer, disclosed pursuant to this part, the
Department may conduct testing of that equipment under this subpart by
means of a test notice addressed to the manufacturer in accordance with
the following requirements:
(1) The test notice procedure will only be followed after the
Department has examined the underlying test data (or, where
appropriate, data as to use of an AEDM) provided by the manufacturer
and after the manufacturer has been offered the opportunity to meet
with the Department to verify, as applicable, compliance with the
applicable efficiency standard, or the accuracy of labeling
information, or both. In addition, where compliance of a basic model
was certified based on an AEDM, the Department shall have the
discretion to pursue the provisions of Sec. 432.12(a)(4)(iii) prior to
invoking the test notice procedure. The Department shall be permitted
to observe any reverification procedures undertaken pursuant to this
subpart, and to inspect the results of such reverification.
(2) The Department will mail or deliver the test notice to the
plant manager or other responsible official, as designated by the
manufacturer.
(3) The test notice will specify the basic model to be selected for
testing, the method of selecting the test sample, the date and time at
which testing shall be initiated, the date by which testing is
scheduled to be completed and the facility at which testing will be
conducted. The test notice may also provide for situations in which the
specified basic model is unavailable for testing, and may include
alternative basic models. The specified basic model may be one either
that the manufacturer has rated by actual testing or that it has rated
by the use of an AEDM.
(4) The Department may require in the test notice that the
manufacturer shall ship at his expense a reasonable number of units of
a basic model specified in such test notice to a testing laboratory
designated by the Department. The number of units of a basic model
specified in a test notice shall not exceed twenty (20).
[[Page 45524]]
(5) Except as required or provided in paragraphs (a)(6) or (a)(7)
of this section, initially the Department will test five units.
(6) Except as provided in paragraph (a)(7) of this section, if
fewer than five units of a basic model are available for testing when
the manufacturer receives the test notice, then
(i) DOE will test the available unit(s); or
(ii) If one or more other units of the basic model are expected to
become available within six months, DOE may instead, at its discretion,
test either:
(A) The available unit(s) and one or more of the other units that
subsequently become available (up to a maximum of twenty); or
(B) Up to twenty of the other units that subsequently become
available.
(7) Notwithstanding paragraphs (a)(5) and (a)(6) of this section,
if testing of the available or subsequently available units of a basic
model would be impractical, as for example where a basic model is very
large, has unusual testing requirements, or has limited production, the
Department may in its discretion decide to base the determination of
compliance on the testing of fewer than the available number of units,
if the manufacturer so requests and demonstrates that the criteria of
this paragraph are met.
(8) When testing units under paragraphs (a)(5), (a)(6), or (a)(7)
of this section, DOE shall perform the following number of tests:
(i) If DOE tests four or more units, it will test each unit once;
(ii) If DOE tests two or three units, it will test each unit twice;
or
(iii) If DOE tests one unit, it will test that unit four times.
(9) Within five working days of the time the units are selected,
the manufacturer shall ship the specified test units of the basic model
to the testing laboratory.
(b) Testing laboratory. Whenever the Department conducts
enforcement testing at a designated laboratory in accordance with a
test notice under this section, the resulting test data shall
constitute official test data for that basic model. Such test data will
be used by the Department to make a determination of compliance or
noncompliance.
(c) Sampling. The determination that a manufacturer's basic model
complies with its labeled efficiency, or the applicable energy
efficiency standard, shall be based on the testing conducted in
accordance with the statistical sampling procedures set forth in
Appendix B of this subpart and the test procedures specified for
distribution transformers.
(d) Test unit selection. The Department shall select a batch, a
batch sample, and test units from the batch sample in accordance with
the following provisions of this paragraph and the conditions specified
in the test notice.
(1) The batch may be subdivided by the Department utilizing
criteria specified in the test notice.
(2) The Department will then randomly select a batch sample of up
to 20 units from one or more subdivided groups within the batch. The
manufacturer shall keep on hand all units in the batch sample until
such time as the basic model is determined to be in compliance or non-
compliance.
(3) The Department will randomly select individual test units
comprising the test sample from the batch sample.
(4) All random selection shall be achieved by sequentially
numbering all of the units in a batch sample and then using a table of
random numbers to select the units to be tested.
(e) Test unit preparation.
(1) Prior to and during the testing, a test unit selected in
accordance with paragraph (d) of this section shall not be prepared,
modified, or adjusted in any manner unless such preparation,
modification, or adjustment is allowed by the applicable Department of
Energy test procedure.
(2) No quality control, testing, or assembly procedures shall be
performed on a test unit, or any parts and sub-assemblies thereof, that
is not performed during the production and assembly of all other units
included in the basic model.
(3) A test unit shall be considered defective if such unit is
inoperative or is found to be in noncompliance due to failure of the
unit to operate according to the manufacturer's design and operating
instructions. Defective units, including those damaged due to shipping
or handling, shall be reported immediately to the Department. The
Department shall authorize testing of an additional unit on a case-by-
case basis.
(f) Testing at manufacturer's option.
(1) If a manufacturer's basic model is determined to be in
noncompliance with the applicable energy performance standard at the
conclusion of Department testing in accordance with the sampling plan
specified in Appendix B of this subpart, the manufacturer may request
that the Department conduct additional testing of the basic model
according to procedures set forth in Appendix B of this subpart and the
test procedures specified for distribution transformers.
(2) All units tested under this paragraph shall be selected and
tested in accordance with the provisions given in paragraphs (a)(9),
(b), (d) and (e) of this section.
(3) The manufacturer shall bear the cost of all testing conducted
under this paragraph.
(4) The manufacturer shall cease distribution of the basic model
tested under the provisions of this paragraph from the time the
manufacturer elects to exercise the option provided in this paragraph
until the basic model is determined to be in compliance. The Department
may seek civil penalties for all units distributed during such period.
(5) If the additional testing results in a determination of
compliance, a notice of allowance to resume distribution shall be
issued by the Department.
Appendix A to Subpart B of Part 432--Uniform Test Method for Measuring
the Energy Consumption of Distribution Transformers
1.0 Definitions
The definitions contained in Sec. Sec. 432.2 and 432.10 are
applicable to this Appendix A.
2.0 Accuracy Requirements
Equipment and methods for loss measurement shall be sufficiently
accurate that measurement error will be limited to the values shown
in Table 2.1.
Table 2.1--Test System Accuracy Requirements for Each Measured Quantity
------------------------------------------------------------------------
Test system
Measured quantity accuracy
------------------------------------------------------------------------
Power Losses............................................
3.0 %
Voltage.................................................
0.5 %
Current.................................................
0.5 %
Resistance..............................................
0.5 %
Temperature.............................................
1.0 [deg]C
------------------------------------------------------------------------
Only instrument transformers meeting the 0.3 metering accuracy
class, or better, may be used under this test method.
3.0 Resistance Measurements
3.1 General Considerations
Measure or establish the winding temperature at the time of the
winding resistance measurement.
Measure the direct current resistance (Rdc) of
transformer windings by one of the methods outlined in section 3.3.
The methods of section 3.5 must be used to correct load losses to
the applicable reference temperature from the temperature at which
they are measured. Observe precautions while taking measurements,
such as those in section 3.4, in order to maintain measurement
uncertainty limits specified in Table 2.1.
3.2 Temperature Determination of Windings and Pre-conditions for
Resistance Measurement
Make temperature measurements in protected areas where the air
temperature is
[[Page 45525]]
stable and there are no drafts. Determine the winding temperature
(Tdc) for liquid-immersed and dry-type distribution
transformers by the methods described in sections 3.2.1 and 3.2.2,
respectively.
3.2.1 Liquid-Immersed Distribution Transformers
Record the winding temperature (Tdc) of liquid-
immersed transformers as the average of top and bottom thermocouples
or other temperature sensing devices applied to the outside of the
transformer tank. The top sensor should be located at the level of
the oil and the bottom sensor should be near the tank bottom or at
the lower radiator header if applicable.
Make this determination under either of the following
conditions:
(a) The windings have been under insulating liquid with no
excitation and no current in the windings for four hours before the
dc resistance is measured; or
(b) The temperature of the insulating liquid has stabilized, and
the difference between the top and bottom temperature does not
exceed 5 [deg]C.
3.2.2 Dry-Type Distribution Transformers
Record the winding temperature (Tdc) of ventilated
dry-type transformers as the average of readings of four or more
thermometers, thermocouples, or other suitable temperature sensors
inserted within the coils. Sensing points of the measuring devices
must be placed as close as possible to the winding conductors.
For sealed units such as epoxy-coated or epoxy-encapsulated
distribution transformers, the temperature of the windings must be
recorded as either:
(1) The average of four or more temperature sensors located on
the enclosure and cover as close to different parts of the winding
assemblies as possible; or
(2) After allowing a stabilizing interval with no excitation and
no current in the windings for at least 24 hours, the ambient
temperature of the test area.
The following conditions must be met immediately before taking
cold-resistance measurements:
(a) All internal temperatures measured by the internal
temperature sensors must not differ from the test area ambient
temperature by more than 2 [deg]C.
(b) Enclosure surface temperatures for sealed units must not
differ from the test area ambient temperature by more than 2 [deg]C.
(c) Test area ambient temperature should not have changed by
more than 3 [deg]C for 3 hours before the test.
(d) Neither voltage nor current has been applied to the unit
under test for 24 hours. In addition, the period since application
of voltage or current must exceed 24 hours by any added amount of
time necessary for the temperature of the transformer windings to
stabilize at the level of the ambient temperature. However, this
added amount of time need not exceed 24 hours.
3.3 Resistance Measurement Methods
Make resistance measurements using either the resistance bridge
method, the voltmeter-ammeter method or a resistance meter. In each
instance when this Uniform Test Method is used to test more than one
unit of a basic model to determine the efficiency of that basic
model, the resistance of the units being tested may be determined
from making resistance measurements on only one of the units.
3.3.1 Resistance Bridge Methods
If the resistance bridge method is selected, use either the
Wheatstone or Kelvin bridge circuit (or the equivalent of either).
3.3.1.1 Wheatstone Bridge
This bridge is best suited for measuring resistances larger than
ten ohms. A schematic diagram of a Wheatstone bridge with a
representative transformer under test is shown in Figure 3.1.
[GRAPHIC] [TIFF OMITTED] TP29JY04.002
Where:
Rdc is the resistance of the transformer winding being
measured,
Rs is a standard resistor having the resistance
Rs,
Ra, Rb are two precision resistors with
resistance values Ra and Rb, respectively; at
least one resistor must have a provision for resistance adjustment,
Rt is a resistor for reducing the time constant of the
circuit,
D is a null detector, which may be either a micro ammeter or
microvoltmeter or equivalent instrument for observing that no signal
is present when the bridge is balanced, and
Vdc is a source of dc voltage for supplying the power to
the Wheatstone Bridge.
In the measurement process, turn on the source (Vdc),
and adjust the resistance ratio (Ra/Rb) to
produce zero signal at the detector (D). Determine the winding
resistance by using equation 3-1 as follows:
Rdc = Rs (Ra/Rb) (3-1)
3.3.1.2 Kelvin Bridge
This bridge separates the resistance of the connecting
conductors to the transformer winding being measured from the
resistance of the winding, and therefore is best suited for
measuring resistances of ten ohms and smaller. A schematic diagram
of a Kelvin bridge with a representative transformer under test is
shown in Figure 3.2.
[[Page 45526]]
[GRAPHIC] [TIFF OMITTED] TP29JY04.003
The Kelvin Bridge has seven of the same type of components as in
the Wheatstone Bridge. It has two more resistors than the Wheatstone
bridge, Ra1 and Rb1. At least one of these
resistors must have adjustable resistance. In the measurement
process, the source is turned on, two resistance ratios
(Ra/Rb) and (Ra1/Rb1)
are adjusted to be equal, and then the two ratios are adjusted
together to balance the bridge producing zero signal at the
detector. Determine the winding resistance by using equation 3-2 as
follows:
Rdc = Rs (Ra/Rb) (3-2),
as with the Wheatstone bridge, with an additional condition that:
(Ra/Rb) = (Ra1/Rb1) (3-
3)
The Kelvin bridge provides two sets of leads, current-carrying
and voltage-sensing, to the transformer terminals and the standard
resistor, thus eliminating voltage drops from the measurement in the
current-carrying leads as represented by Rd.
3.3.2 Voltmeter-Ammeter Method
Employ the voltmeter-ammeter method only if the rated current of
the winding is greater than one ampere and the test current is
limited to 15% of the winding current. Connect the transformer
winding under test to the circuit shown in Figure 3.3.
[GRAPHIC] [TIFF OMITTED] TP29JY04.004
Where:
A is an ammeter or a voltmeter-shunt combination for measuring the
current (Imdc) in the transformer winding,
V is a voltmeter with sensitivity in the millivolt range for
measuring the voltage (Vmdc) applied to the transformer
winding,
Rdc is the resistance of the transformer winding being
measured,
Rt is a resistor for reducing the time constant of the
circuit, and
Vdc is a source of dc voltage for supplying power to the
measuring circuit.
To perform the measurement, turn on the source to produce
current no larger than 15 percent of the rated current for the
winding. Wait until the current and voltage readings have stabilized
and then take simultaneous readings of voltage and current.
Determine the winding resistance Rdc by using equation 3-
4 as follows:
Rdc = (Vmdc/Imdc) (3-4)
Where:
Vmdc is the voltage measured by the voltmeter V, and
[[Page 45527]]
Imdc is the current measured by the ammeter A.
As shown in Figure 3.3, separate current and voltage leads must
be brought to the transformer terminals. (This eliminates the errors
due to lead and contact resistance.)
3.3.3 Resistance Meters
Resistance meters may be based on voltmeter-ammeter, or
resistance bridge, or some other operating principle. A particular
meter may be used to measure a transformer's winding resistance only
if the meter's specifications for resistance range, current range,
and ability to measure highly inductive resistors cover the
characteristics of the transformer being tested. Also the meter's
specifications for accuracy must meet the applicable criteria of
Table 2.1 in section 2.0.
3.4 Precautions in Measuring Winding Resistance
3.4.1 Required actions
The following guidelines must be observed when making resistance
measurements:
(a) Use separate current and voltage leads when measuring small
(< 10 ohms) resistance.
(b) Use null detectors in bridge circuits, and measuring
instruments in voltmeter-ammeter circuits, that have sensitivity and
resolution sufficient to enable observation of at least 0.1 percent
change in the measured resistance.
(c) Maintain the dc test current at or below 15 percent of the
rated winding current.
(d) Inclusion of a stabilizing resistor Rt (see
section 3.4.2) will require higher source voltage.
(e) Disconnect the null detector (if a bridge circuit is used)
and voltmeter from the circuit before the current is switched off,
and switch off current by a suitable insulated switch.
3.4.2 Guideline for Time Constant
The following guideline is suggested for the tester as a means
to facilitate the measurement of resistance in accordance with the
accuracy requirements of section 2.0:
The accurate reading of resistance Rdc may be
facilitated by shortening the time constant. This is done by
introducing a resistor Rt in series with the winding
under test in both the bridge and voltmeter-ammeter circuits as
shown in Figures 3.1 to 3.3. The relationship for the time constant
is:
Tc = (Ltc/Rtc) (3-5)
Where:
Tc is the time constant in seconds,
Ltc is the total magnetizing and leakage inductance of
the winding under test, in henries, and
Rtc is the total resistance in ohms, consisting of
Rt in series with the winding resistance Rdc.
Because Rtc is in the denominator of the expression
for the time constant, increasing the size of resistor
Rtc will decrease the time constant. If the time constant
in a given test circuit is too high for the resistance readings to
be stable, then a higher resistance can be substituted for the
existing Rtc, and successive replacements can be made
until adequate stability is reached.
3.5 Conversion of Resistance Measurements
Resistance measurements must be corrected, from the temperature
at which the winding resistance measurements were made, to the
reference temperature. As specified in these test procedures, the
reference temperature for liquid-immersed transformers loaded at 50
percent of the rated load is 55 [deg]C. For medium-voltage, dry-type
transformers loaded at 50 percent of the rated load, and for low-
voltage, dry-type transformers loaded at 35 percent of the rated
load, the reference temperature is 75[deg]C.
Correct measurement temperatures to the DOE reference
temperature using equation 3-6 as follows:
Rts = Rdc [(Ts + Tk)/
(Tdc + Tk)] (3-6)
Where:
Rts is the resistance at the reference temperature,
Ts,
Rdc is the measured resistance at temperature,
Tdc,
Ts is the reference temperature in [deg]C,
Tdc is the temperature at which resistance was measured
in [deg]C, and
Tk is 234.5 [deg]C for copper or 225 [deg]C for aluminum.
Where copper and aluminum windings are employed in the same
transformer, use 229 [deg]C.
4.0 Loss Measurement
4.1 General Considerations
The efficiency of a transformer is computed from the total
transformer losses, which are determined from the measured value of
the no-load loss and load loss power components. Each of these two
power loss components is measured separately using functionally
identical test sets. The measured quantities will need correction
for instrumentation losses and may need corrections for known phase
angle errors in measuring equipment and for the wave form distortion
in the test voltage. Any power loss not measured at the applicable
reference temperature must be adjusted to that reference
temperature. The measured load loss must also be adjusted to a
specified output loading level if not measured at the specified
output loading level.
4.2 Measurement of Power Losses
4.2.1 No-Load Loss
Measure the no-load loss and apply corrections as described in
section 4.4, using the appropriate test set as described in section
4.3.
4.2.2 Load Loss
Measure the load loss and apply corrections as described in
section 4.5, using the appropriate test set as described in section
4.3.
4.3 Test Sets
The same test set may be used for both the no-load loss and load
loss measurements provided the range of the test set encompasses the
test requirements of both tests. Calibrate the test set to national
standards to meet the tolerances in Table 2.1 in section 2.0. In
addition, the wattmeter, current measuring system and voltage
measuring system must be calibrated separately if the overall test
set calibration is outside the tolerance as specified in section 2
or the individual phase angle error exceeds the values specified in
section 4.5.3.
A test set based on the wattmeter-voltmeter-ammeter principle
may be used to measure the power loss and the applied voltage and
current of a transformer where the transformer's test current and
voltage are within the measurement capability of the measuring
instruments. Current and voltage transformers, known collectively as
instrument transformers, or other scaling devices such as resistive
or capacitive dividers for voltage, may be used in the above
circumstance, and must be used in place of an instrument to measure
current or voltage where the current or voltage of the transformer
under test exceeds the measurement capability of such instrument.
Thus, a test set may include a combination of measuring instruments
and instrument transformers (or other scaling devices), so long as
the current or voltage of the transformer under test does not exceed
the measurement capability of any of the instruments.
4.3.1 Single Phase Test Sets
Use these for testing single phase distribution transformers.
4.3.1.1 Without Instrument Transformers
A single-phase test set without an instrument transformer is
shown in Figure 4.1.
[[Page 45528]]
[GRAPHIC] [TIFF OMITTED] TP29JY04.005
Where:
W is a wattmeter used to measure Pnm and Plm,
the no-load and load loss power, respectively,
Vrms is a true root-mean-square (rms) voltmeter used to
measure Vr(nm) and Vlm, the rms test voltages
in no-load and load loss measurements, respectively,
Vav is an average sensing voltmeter, calibrated to
indicate rms voltage for sinusoidal waveforms and used to measure
Va(nm), the average voltage in no-load loss measurements,
A is an rms ammeter used to measure test current, especially
Ilm, the load loss current, and
(SC) is a conductor for providing a short-circuit across the output
windings for the load loss measurements.
Either the primary or the secondary winding can be connected to
the test set. However, more compatible voltage and current levels
for the measuring instruments are available if for no-load loss
measurements the secondary (low voltage) winding is connected to the
test set, and for load loss measurements the primary winding is
connected to the test set. Use the average-sensing voltmeter,
Vav, only in no-load loss measurements.
4.3.1.2 With Instrument Transformers
A single-phase test set with instrument transformers is shown in
Figure 4.2. This circuit has the same four measuring instruments as
that in Figure 4.1. The current and voltage transformers, designated
as (CT) and (VT), respectively, are added.
[GRAPHIC] [TIFF OMITTED] TP29JY04.006
4.3.2 Three-Phase Test Sets
Use these for testing three-phase distribution transformers.
4.3.2.1 Without Instrument Transformers
A three-phase test set without instrument transformers is shown
in Figure 4.3. This test set is essentially the same circuit shown
in Figure 4.1 repeated three times, and the instruments are
individual devices as shown. As an alternative, the entire
instrumentation system of a three-phase test set without
transformers may consist of a multi-function analyzer.
[[Page 45529]]
[GRAPHIC] [TIFF OMITTED] TP29JY04.007
Either group of windings, the primary or the secondary, can be
connected in wye or delta configuration. If both groups of windings
are connected in the wye configuration for the no-load test, the
neutral of the winding connected to the test set must be connected
to the neutral of the source to provide a return path for the
neutral current.
In the no-load loss measurement, the voltage on the winding must
be measured. Therefore a provision must be made to switch the
voltmeters for line-to-neutral measurements for wye-connected
windings and for line-to-line measurements for delta-connected
windings.
4.3.2.2 With Instrument Transformers
A three-phase test set with instrument transformers is shown in
Figure 4.4. This test set is essentially the same circuit shown in
Figure 4.2 repeated three times. Provision must be made to switch
the voltmeters for line-to-neutral and line-to-line measurements as
in section 4.3.2.1. The voltage sensors (``coils'') of the
wattmeters must always be connected in the line-to-neutral
configuration.
[GRAPHIC] [TIFF OMITTED] TP29JY04.008
[[Page 45530]]
4.3.3 Test Set Neutrals
A four-wire, three-wattmeter test circuit must be used in making
measurements. For delta-wound transformers, a neutral deriving
transformer must be used to obtain neutral and ground for the test.
4.4 No-Load Losses: Measurement and Calculations
4.4.1 General Considerations
Make measurement corrections:
(1) For instrumentation losses;
(2) When the waveform of the applied voltage is non-sinusoidal;
and
(3) When the core temperature or liquid temperature is outside
the 20 [deg]C 10 [deg]C range.
4.4.2 No-Load Loss Test
The purpose of the no-load loss test is to measure no-load
losses at a specified excitation voltage and a specified frequency.
The no-load loss determination must be based on a sine-wave voltage
corrected to the reference temperature. Connect either of the
transformer windings, primary or secondary, to the appropriate test
set of Figures 4.1 to 4.4, giving consideration to precaution (b)
below. Leave the unconnected winding(s) open circuited. Apply the
rated voltage at rated frequency, as measured by the average-sensing
voltmeter, to the transformer. Take the readings of the wattmeter(s)
and the average-sensing and true rms voltmeters. Observe the
precautions (a), (b), and (c) below:
(a) Voltmeter connections. When correcting to a sine-wave basis
using the average-voltmeter method, the voltmeter connections must
be such that the waveform applied to the voltmeters is the same as
the waveform across the energized windings.
(b) Energized windings. Either the high voltage or the low
voltage winding of the transformer under test may be energized.
Energize not less than 25 percent of the winding.
(c) Voltage and frequency. The no-load loss test must be
conducted with rated voltage impressed across the transformer
terminals using a voltage source at a frequency equal to the rated
frequency of the transformer under test, unless otherwise specified.
Adjust the voltage to the specified value as indicated by the
average-sensing voltmeter. Record the values of rms voltage, rms
current, electrical power, and average voltage as close to
simultaneously as possible. For a three-phase transformer, take all
of the readings on one phase before proceeding to the next, and
record the average of the three rms voltmeter readings as the rms
voltage value.
Note: When the tester uses a power supply that is not
synchronized with an electric utility grid, such as a dc/ac motor-
generator set, check the frequency and maintain it within < plus-
minus>0.5 percent of the rated frequency of the transformer under
test. A power source that is directly connected to, or synchronized
with, an electric utility grid need not be monitored for frequency.
4.4.3 Corrections
4.4.3.1 Correction for Instrumentation Losses
Determine the losses attributable to the voltmeters, ammeter,
and wattmeter, and to the instrument transformers if they are used,
and deduct these losses from the measurement of total no-load
losses.
4.4.3.2 Correction for Non-Sinusoidal Applied Voltage
The measured value of no-load loss must be corrected to a
sinusoidal voltage, except when waveform distortion in the test
voltage causes the magnitude of the correction to be less than 1%.
In such a case, no correction is required.
To make a correction where the distortion requires a correction
of 5% or less, use equation 4-1. If the distortion requires a
correction to be greater than 5%, improve the test voltage and re-
test. Repeat until the distortion requires a correction of 5% or
less.
Determine the no-load losses of the transformer corrected for
sine-wave basis from the measured value by using equation 4-1 as
follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.009
Where:
Pncl is the no-load loss corrected to a sine-wave basis
at the temperature (Tnm) at which no-load loss is
measured,
Pnm is the measured no-load loss at temperature
Tnm,
P1 is the per unit hysteresis loss,
P2 is the per unit eddy-current loss,
P1 + P2 = 1,
[GRAPHIC] [TIFF OMITTED] TP29JY04.010
Vr(nm) is the test voltage measured by rms voltmeter, and
Va(nm) is the test voltage measured by average-voltage
voltmeter.
The two loss components (P1 and P2) are
assumed equal in value, each assigned a value of 0.5 per unit,
unless the actual measurement-based values of hysteresis and eddy-
current losses are available (in per unit form), in which case the
actual measurements apply.
4.4.3.3 Correction of No-Load Loss to Reference Temperature
After correcting the measured no-load loss for waveform
distortion, correct the loss to the reference temperature of 20
[deg]C. If the no-load loss measurements were made between 10 [deg]C
and 30 [deg]C, this correction is not required. If the correction to
reference temperature is applied, then the core temperature of the
transformer during no-load loss measurement (Tnm) must be
determined within 10 [deg]C of the true average core
temperature. Correct the no-load loss to the reference temperature
by using equation 4-2 as follows:
Pnc=Pncl [(1 + 0.00065 (Tnm -
Tnr)] (4-2)
Where:
Pnc is the no-load losses corrected for waveform
distortion and then to the reference temperature of 20[deg]C,
Pncl is the no-load losses, corrected for waveform
distortion, at temperature Tnm,
Tnm is the core temperature during the measurement of no-
load losses, and
Tnr is the reference temperature, 20 [deg]C.
4.5 Load Losses: Measurement and Calculations
4.5.1 General Considerations
The load losses of a transformer are those losses incident to a
specified load carried by the transformer. Load losses consist of
ohmic loss in the windings due to the load current and stray losses
due to the eddy currents induced by the leakage flux in the
windings, core clamps, magnetic shields, tank walls, and other
conducting parts. The ohmic loss of a transformer varies directly
with temperature, whereas the stray losses vary inversely with
temperature.
For a transformer with a tap changer, the test must be conducted
at the rated current and voltage of the nominal tap position.
4.5.2 Tests for Measuring Load Losses
Connect the transformer with either the high-voltage or low-
voltage windings to the appropriate test set. Then short-circuit the
winding that was not connected to the test set. Apply a voltage at
the rated frequency (of the transformer under test) to the connected
windings to produce the rated current in the transformer. Take the
readings of the wattmeter(s), the ammeters(s), and rms voltmeter(s).
Regardless of the test set selected, the following preparatory
requirements must be satisfied for accurate test results:
(a) Determine the temperature of the windings using the
applicable method in section 3.2.1 or section 3.2.2.
(b) The conductors used to short-circuit the windings must have
a cross-sectional area equal to, or greater than, the corresponding
transformer leads.
(c) When the tester uses a power supply that is not synchronized
with an electric utility grid, such as a dc/ac motor-generator set,
follow the provisions of the Note in section 4.4.2.
4.5.3 Corrections
4.5.3.1 Correction for Instrumentation Losses
Determine the losses attributable to the voltmeters, ammeter,
wattmeter and short-circuiting conductor (SC), and to the instrument
transformers if they are used, and deduct these losses from the
measurement of total load losses.
4.5.3.2 Correction for Phase Angle Errors
Corrections for phase angle errors are not required if the
instrumentation is calibrated over the entire range of power factors
and phase angle errors. Otherwise, determine whether to correct for
phase angle errors from the magnitude of the normalized per unit
correction, [beta]n, obtained by using equation 4-3 as
follows:
[[Page 45531]]
[GRAPHIC] [TIFF OMITTED] TP29JY04.011
The correction must be applied if [beta]n is outside
the limits of 0.01. If [beta]n is within the
limits of 0.01, the correction is permitted but not
required.
If the correction for phase angle errors is to be applied, first
examine the total system phase angle ([beta]w-
[beta]v+[beta]c). Where the total system phase
angle is equal to or less than 12 milliradians (41 minutes), use either equation 4-4 or 4-5 to correct the
measured load loss power for phase angle errors, and where the total
system phase angle exceeds 12 milliradians (41 minutes) use equation 4-5, as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.012
[GRAPHIC] [TIFF OMITTED] TP29JY04.013
The symbols in this section (4.5.3.2) have the following
meanings:
Plc1 is the corrected wattmeter reading for phase angle
errors,
Plm is the actual wattmeter reading,
Vlm is the measured voltage at the transformer winding,
Ilm is the measured rms current in the transformer
winding,
[GRAPHIC] [TIFF OMITTED] TP29JY04.014
[GRAPHIC] [TIFF OMITTED] TP29JY04.015
[beta]w is the phase angle error (in radians) of the
wattmeter; the error is positive if the phase angle between the
voltage and current phasors as sensed by the wattmeter is smaller
than the true phase angle, thus effectively increasing the measured
power,
[beta]v is the phase angle error (in radians) of the
voltage transformer; the error is positive if the secondary voltage
leads the primary voltage, and
[beta]c is the phase angle error (in radians) of the
current transformer; the error is positive if the secondary current
leads the primary current.
The instrumentation phase angle errors used in the correction
equations must be specific for the test conditions involved.
4.5.3.3 Temperature Correction of Load Loss
When the measurement of load loss is made at a temperature
Tlm that is different from the reference temperature, use
the procedure summarized in the equations 4-6 to 4-10 to correct the
measured load loss to the reference temperature.
Calculate the ohmic loss (Pe) by using equation 4-6
as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.016
Obtain the stray loss by subtracting the calculated ohmic loss
from the measured load loss, by using equation 4-7 as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.017
Correct the ohmic and stray losses to the reference temperature
for the load loss by using equations 4-8 and 4-9, respectively, as
follows:
[[Page 45532]]
[GRAPHIC] [TIFF OMITTED] TP29JY04.018
Add the ohmic and stray losses, corrected to the reference
temperature, to give the load loss, Plc2, at the
reference temperature, by using equation (4-10) as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.020
The symbols in this section (4.5.3.3) have the following
meanings:
Ilm(p) is the primary current in amperes,
Ilm(s) is the secondary current in amperes,
Pe is the ohmic loss in the transformer in watts at the
temperature Tlm,
Pe(p) is the ohmic loss in watts in the primary winding
at the temperature Tlm,
Pe(s) is the ohmic loss in watts in the secondary winding
at the temperature Tlm,
Per is the ohmic loss in watts corrected to the reference
temperature,
Plc1 is the measured load loss in watts, corrected for
phase angle error, at the temperature Tlm,
Plc2 is the load loss at the reference temperature,
Ps is the stray loss in watts at the temperature
Tlm,
Psr is the stray loss in watts corrected to the reference
temperature,
Rdc(p) is the measured dc primary winding resistance in
ohms,
Rdc(s) is the measured dc secondary winding resistance in
ohms,
Tk is the critical temperature in degrees Celsius for the
material of the transformer windings. Where copper is used in both
primary and secondary windings, Tk is 234.5 [deg]C; where
aluminum is used in both primary and secondary windings,
Tk is 225 [deg]C; where both copper and aluminum are used
in the same transformer, the value of 229 [deg]C is used for
Tk,
Tk(p) is the critical temperature in degrees Celsius for
the material of the primary winding: 234.5 [deg]C if copper and 225
[deg]C if aluminum,
Tk(s) is the critical temperature in degrees Celsius for
the material of the secondary winding: 234.5 [deg]C if copper and
225 [deg]C if aluminum,
Tlm is the temperature in degrees Celsius at which the
load loss is measured,
Tlr is the reference temperature for the load loss in
degrees Celsius,
Tdc is the temperature in degrees Celsius at which the
resistance values are measured, and
N1/N2 is the ratio of the number of turns in
the primary winding (N1) to the number of turns in the
secondary winding (N2); for a primary winding with taps,
N1 is the number of turns used when the voltage applied
to the primary winding is the rated primary voltage.
5.0 Determining the Efficiency Value of the Transformer
This section presents the equations to use in determining the
efficiency value of the transformer at the required reference
conditions and at the specified loading level. The details of
measurements are described in sections 3.0 and 4.0.
5.1 Output Loading Level Adjustment
If the output loading level for energy efficiency is different
from the level at which the load loss power measurements were made,
then adjust the corrected load loss power, Plc2, by using
equation 5-1 as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.022
Where:
Plc is the adjusted load loss power to the specified
energy efficiency load level,
Plc2 is as calculated in section 4.5.3.3,
Por is the rated transformer output power (name plate),
Pos is the specified energy efficiency load level, where
Pos, = PorL2, and
L is the per unit load level, e.g., if the load level is 50 percent
then ``L'' will be 0.5.
5.2 Total Loss Power Calculation
Calculate the corrected total loss power by using equation 5-2
as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.019
Where:
Pts is the corrected total loss power adjusted for the
transformer output loading specified by the standard,
Pnc is as calculated in section 4.4.3.3, and
Plc is as calculated in section 5.1.
5.3 Energy Efficiency Calculation
Calculate efficiency ([eta]) at specified energy efficiency load
level, Pos, by using equation 5-3 as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.023
Where:
Pos is as described and calculated in section 5.1, and
Pts is as described and calculated in section 5.2.
5.4 Significant Figures in Power Loss and Efficiency Data
In measured and calculated data, retain enough significant
figures to provide at least 1 percent resolution in power loss data
and 0.01 percent resolution in efficiency data.
6.0 Test Equipment Calibration and Certification
6.1 Test Equipment
Test equipment and measuring instruments must be maintained
properly, and calibration records must be maintained. The
calibration of the test set shall confirm the accuracy of the test
set to that specified in section 2.0.
The party performing the tests shall control, calibrate and
maintain measuring and test equipment, whether or not it owns the
equipment, has the equipment on loan, or the equipment is provided
by another party. Equipment shall be used in a manner which assures
that measurement uncertainty
[[Page 45533]]
is known and is consistent with the required measurement capability.
6.2 Calibration and Certification
The party performing the tests must:
(a) Identify the measurements to be made, the accuracy required
(section 2.0) and select the appropriate measurement and test
equipment;
(b) At prescribed intervals, or prior to use, identify, check
and calibrate, if needed, all measuring and test equipment systems
or devices that affect test accuracy, against certified equipment
having a known valid relationship to nationally recognized
standards; where no such standards exist, the basis used for
calibration must be documented;
(c) Establish, document and maintain calibration procedures,
including details of equipment type, identification number,
location, frequency of checks, check method, acceptance criteria and
action to be taken when results are unsatisfactory;
(d) Ensure that the measuring and test equipment is capable of
the accuracy and precision necessary, taking into account the
voltage, current and power factor of the transformer under test;
(e) Identify measuring and test equipment with a suitable
indicator or approved identification record to show the calibration
status;
(f) Maintain calibration records for measuring and test
equipment;
(g) Assess and document the validity of previous test results
when measuring and test equipment is found to be out of calibration;
(h) Ensure that the environmental conditions are suitable for
the calibrations, measurements and tests being carried out;
(i) Ensure that the handling, preservation and storage of
measuring and test equipment is such that the accuracy and fitness
for use is maintained; and
(j) Safeguard measuring and test facilities, including both test
hardware and test software, from adjustments which would invalidate
the calibration setting.
Appendix B to Subpart B of Part 432--Sampling Plan for Enforcement
Testing
Step 1. The number of units in the sample (m1) shall
be in accordance with Sec. Sec. 432.13(a)(4), 432.13(a)(5),
432.13(a)(6) and 432.13(a)(7) and shall not be greater than twenty.
The number of tests in the first sample (n1) shall be in
accordance with Sec. 432.13(a)(8) and shall be not fewer than four.
Step 2. Compute the mean (X1) of the measured energy
performance of the n1 tests in the first sample by using
equation 1 as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.024
Where Xi is the measured efficiency of test i.
Step 3. Compute the sample standard deviation (S1) of
the measured efficiency of the n1 tests in the first
sample by using equation 2 as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.025
Step 4. Compute the standard error (SE(X1)) of the
mean efficiency of the first sample by using equation 3 as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.026
Step 5. Compute the sample size discount (SSD(m1)) by
using equation 4 as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.027
Where m1 is the number of units in the sample, and
RE is the applicable EPCA efficiency when the test is to
determine compliance with the applicable statutory standard, or is
the labeled efficiency when the test is to determine compliance with
the labeled efficiency value.
Step 6. Compute the lower control limit (LCL1) for
the mean of the first sample by using equation 5 as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.028
Where t is the 2.5th percentile of a t-distribution for a sample
size of n1, which yields a 97.5 percent confidence level
for a one-tailed t-test.
Step 7. Compare the mean of the first sample (X1)
with the lower control limit (LCL1) to determine one of
the following:
(i) If the mean of the first sample is below the lower control
limit, then the basic model is in non-compliance and testing is at
an end.
(ii) If the mean is equal to or greater than the lower control
limit, no final determination of compliance or non-compliance can be
made; proceed to Step 8.
Step 8. Determine the recommended sample size (n) by using
equation 6 as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.029
Where S1 and t have the values used in Steps 3 and 6,
respectively. The factor
[GRAPHIC] [TIFF OMITTED] TP29JY04.030
is based on a 5-percent tolerance in the total power loss.
Given the value of n, determine one of the following:
(i) If the value of n is less than or equal to n1 and
if the mean energy efficiency of the first sample (X1) is
equal to or greater than the lower control limit (LCL1),
the basic model is in compliance and testing is at an end.
(ii) If the value of n is greater than n1, and no
additional units are available for testing, testing is at an end and
the basic model is in non-compliance. If the value of n is greater
than n1, and additional units are available for testing,
select a second sample n2. The size of the n2
sample is determined to be the smallest integer equal to or greater
than the difference n-n1. If the value of n2
so calculated is greater than 20-n1, set n2
equal to 20-n1.
Step 9. After testing the n2 sample, compute the
combined mean (X2) of the measured energy performance of
the n1 and n2 tests of the combined first and
second samples by using equation 7 as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.031
Step 10. Compute the standard error (SE(X2)) of the
mean efficiency of the n1 and n2 tests in the
combined first and second samples by using equation 8 as follows:
[GRAPHIC] [TIFF OMITTED] TP29JY04.032
(Note that S1 is the value obtained above in Step 3.)
Step 11. Set the lower control limit (LCL2) to,
[GRAPHIC] [TIFF OMITTED] TP29JY04.033
Where t has the value obtained in Step 5 and SSD(m1) is
sample size discount from Step 5. Compare the combined sample mean
(X2) to the lower control limit (LCL2) to find
one of the following:
(i) If the mean of the combined sample (X2) is less
than the lower control limit (LCL2), the basic model is
in non-compliance and testing is at an end.
(ii) If the mean of the combined sample (X2) is equal
to or greater than the lower control limit (LCL2), the
basic model is in compliance and testing is at an end.
Manufacturer-Option Testing
If a determination of non-compliance is made in Steps 6, 7 or
11, above, the manufacturer may request that additional
[[Page 45534]]
testing be conducted, in accordance with the following procedures.
Step A. The manufacturer requests that an additional number,
n3, of units be tested, with n3 chosen such
that n1 + n2 + n3 does not exceed
20.
Step B. Compute the mean efficiency, standard error, and lower
control limit of the new combined sample in accordance with the
procedures prescribed in Steps 8, 9, and 10, above.
Step C. Compare the mean performance of the new combined sample
to the lower control limit (LCL2) to determine one of the
following:
(a) If the new combined sample mean is equal to or greater than
the lower control limit, the basic model is in compliance and
testing is at an end.
(b) If the new combined sample mean is less than the lower
control limit and the value of n1 + n2 +
n3 is less than 20, the manufacturer may request that
additional units be tested. The total of all units tested may not
exceed 20. Steps A, B, and C are then repeated.
(c) Otherwise, the basic model is determined to be in non-
compliance.
Subpart C--[Reserved]
Subpart D--[Reserved]
[FR Doc. 04-16576 Filed 7-28-04; 8:45 am]
BILLING CODE 6450-01-P