10 CFR § 431.196 - Energy conservation standards and their effective dates.

§ 431.196 Energy conservation standards and their effective dates.

(a) Low-Voltage Dry-Type Distribution Transformers.

(1) The efficiency of a low-voltage, dry-type distribution transformer manufactured on or after January 1, 2007, but before January 1, 2016, shall be no less than that required for the applicable kVA rating in the table below. Low-voltage dry-type distribution transformers with kVA ratings not appearing in the table shall have their minimum efficiency level determined by linear interpolation of the kVA and efficiency values immediately above and below that kVA rating.

Single-phase		Three-phase
kVA	%	kVA	%
15	97.7	15	97.0
25	98.0	30	97.5
37.5	98.2	45	97.7
50	98.3	75	98.0
75	98.5	112.5	98.2
100	98.6	150	98.3
167	98.7	225	98.5
250	98.8	300	98.6
333	98.9	500	98.7
		750	98.8
		1000	98.9

Note 1 to paragraph (a)(1):

All efficiency values are at 35 percent per-unit load.

(2) The efficiency of a low-voltage, dry-type distribution transformer manufactured on or after January 1, 2016, but before April 23, 2029, shall be no less than that required for the applicable kVA rating in the following table. Low-voltage dry-type distribution transformers with kVA ratings not appearing in the table shall have their minimum efficiency level determined by linear interpolation of the kVA and efficiency values immediately above and below that kVA rating.

Table 2 to Paragraph (a)(1)

Single-phase		Three-phase
kVA		kVA
15	97.70	15	97.89
25	98.00	30	98.23
37.5	98.20	45	98.40
50	98.30	75	98.60
75	98.50	112.5	98.74
100	98.60	150	98.83
167	98.70	225	98.94
250	98.80	300	99.02
333	98.90	500	99.14
		750	99.23
		1000	99.28

Note: All efficiency values are at 35 percent of nameplate-rated load, determined according to the DOE Test Method for Measuring the Energy Consumption of Distribution Transformers under appendix A to this subpart K.

(3) The efficiency of a low-voltage dry-type distribution transformer manufactured on or after April 23, 2029, shall be no less than that required for their kVA rating in the following table. Low-voltage dry-type distribution transformers with kVA ratings not appearing in the table shall have their minimum efficiency level determined by linear interpolation of the kVA and efficiency values immediately above and below that kVA rating.

Table 3 to Paragraph (a)(3)

Single-phase		Three-phase
kVA	Efficiency (%)	kVA	Efficiency (%)
15	98.39	15	98.31
25	98.60	30	98.58
37.5	98.74	45	98.72
50	98.81	75	98.88
75	98.95	112.5	98.99
100	99.02	150	99.06
167	99.09	225	99.15
250	99.16	300	99.22
333	99.23	500	99.31
		750	99.38
		1000	99.42

(b) Liquid-Immersed Distribution Transformers.

(1) The efficiency of a liquid-immersed distribution transformer manufactured on or after January 1, 2010, but before January 1, 2016, shall be no less than that required for their kVA rating in the table below. Liquid-immersed distribution transformers with kVA ratings not appearing in the table shall have their minimum efficiency level determined by linear interpolation of the kVA and efficiency values immediately above and below that kVA rating.

Single-phase		Three-phase
kVA	Efficiency (%)	kVA	Efficiency (%)
10	98.62	15	98.36
15	98.76	30	98.62
25	98.91	45	98.76
37.5	99.01	75	98.91
50	99.08	112.5	99.01
75	99.17	150	99.08
100	99.23	225	99.17
167	99.25	300	99.23
250	99.32	500	99.25
333	99.36	750	99.32
500	99.42	1000	99.36
667	99.46	1500	99.42
833	99.49	2000	99.46
		2500	99.49

Note 3 to paragraph (b)(1):

All efficiency values are at 50 percent per-unit load.

(2) The efficiency of a liquid-immersed distribution transformer, including submersible distribution transformers, manufactured on or after January 1, 2016, but before April 23, 2029, shall be no less than that required for their kVA rating in the following table. Liquid-immersed distribution transformers, including submersible distribution transformers, with kVA ratings not appearing in the table shall have their minimum efficiency level determined by linear interpolation of the kVA and efficiency values immediately above and below that kVA rating.

Table 5 to Paragraph (b)(2)

Single-phase		Three-phase
kVA	Efficiency (%)	kVA	Efficiency (%)
10	98.70	15	98.65
15	98.82	30	98.83
25	98.95	45	98.92
37.5	99.05	75	99.03
50	99.11	112.5	99.11
75	99.19	150	99.16
100	99.25	225	99.23
167	99.33	300	99.27
250	99.39	500	99.35
333	99.43	750	99.40
500	99.49	1000	99.43
667	99.52	1500	99.48
833	99.55	2000	99.51
		2500	99.53

Note: All efficiency values are at 50 percent of nameplate-rated load, determined according to the DOE Test—Procedure, appendix A to this subpart K.

(3) The efficiency of a liquid-immersed distribution transformer, that is not a submersible distribution transformer, manufactured on or after April 23, 2029, shall be no less than that required for their kVA rating in the following table. Liquid-immersed distribution transformers with kVA ratings not appearing in the table shall have their minimum efficiency level determined by linear interpolation of the kVA and efficiency values immediately above and below that kVA rating.

Table 6 to Paragraph (b)(3)

Single-phase		Three-phase
kVA	Efficiency (%)	kVA	Efficiency (%)
10	98.77	15	98.92
15	98.88	30	99.06
25	99.00	45	99.14
37.5	99.10	75	99.22
50	99.15	112.5	99.29
75	99.23	150	99.33
100	99.29	225	99.38
167	99.46	300	99.42
250	99.51	500	99.38
333	99.54	750	99.43
500	99.59	1000	99.46
667	99.62	1500	99.51
833	99.64	2000	99.53
		2500	99.55
		3750	99.54
		5000	99.53

Note: All efficiency values are at 50 percent of nameplate-rated load, determined according to the DOE Test Method for Measuring the Energy Consumption of Distribution Transformers under appendix A to this subpart K.

(4) The efficiency of a submersible distribution transformer, manufactured on or after April 23, 2029, shall be no less than that required for their kVA rating in the following table. Submersible distribution transformers with kVA ratings not appearing in the table shall have their minimum efficiency level determined by linear interpolation of the kVA and efficiency values immediately above and below that kVA rating.

Table 7 to Paragraph (b)(4)

Single-phase		Three-phase
kVA	Efficiency (%)	kVA	Efficiency (%)
10	98.70	15	98.65
15	98.82	30	98.83
25	98.95	45	98.92
37.5	99.05	75	99.03
50	99.11	112.5	99.11
75	99.19	150	99.16
100	99.25	225	99.23
167	99.33	300	99.27
250	99.39	500	99.35
333	99.43	750	99.40
500	99.49	1000	99.43
667	99.52	1500	99.48
833	99.55	2000	99.51
		2500	99.53

Note: All efficiency values are at 50 percent of nameplate-rated load, determined according to the DOE Test—Procedure, appendix A to this subpart K.

(1) The efficiency of a medium-voltage dry-type distribution transformer manufactured on or after January 1, 2010, but before January 1, 2016, shall be no less than that required for their kVA and BIL rating in the table below. Medium-voltage dry-type distribution transformers with kVA ratings not appearing in the table shall have their minimum efficiency level determined by linear interpolation of the kVA and efficiency values immediately above and below that kVA rating.

Single-phase				Three-phase
kVA	BIL*			kVA	BIL
	20-45 kV	46-95 kV	≥96 kV		20-45 kV	46-95 kV	≥96 kV
	Efficiency (%)	Efficiency (%)	Efficiency (%)		Efficiency (%)	Efficiency (%)	Efficiency (%)
15	98.10	97.86		15	97.50	97.18
25	98.33	98.12		30	97.90	97.63
37.5	98.49	98.30		45	98.10	97.86
50	98.60	98.42		75	98.33	98.12
75	98.73	98.57	98.53	112.5	98.49	98.30
100	98.82	98.67	98.63	150	98.60	98.42
167	98.96	98.83	98.80	225	98.73	98.57	98.53
250	99.07	98.95	98.91	300	98.82	98.67	98.63
333	99.14	99.03	98.99	500	98.96	98.83	98.80
500	99.22	99.12	99.09	750	99.07	98.95	98.91
667	99.27	99.18	99.15	1000	99.14	99.03	98.99
833	99.31	99.23	99.20	1500	99.22	99.12	99.09
				2000	99.27	99.18	99.15
				2500	99.31	99.23	99.20

* BIL means basic impulse insulation level.

Note 5 to paragraph (c)(1):

All efficiency values are at 50 percent per-unit load.

(2) The efficiency of a medium-voltage dry-type distribution transformer manufactured on or after January 1, 2016, but before April 23, 2029, shall be no less than that required for their kVA and BIL rating in the following table. Medium-voltage dry-type distribution transformers with kVA ratings not appearing in the table shall have their minimum efficiency level determined by linear interpolation of the kVA and efficiency values immediately above and below that kVA rating.

Table 9 to Paragraph (c)(2)

kVA	Single-phase			kVA	Three-phase
	BIL ¹				BIL
	20-45 kV	46-95 kV	≥96 kV		20-45 kV	46-95 kV	≥96 kV
	Efficiency (%)	Efficiency (%)	Efficiency (%)		Efficiency (%)	Efficiency (%)	Efficiency (%)
15	98.10	97.86		15	97.50	97.18
25	98.33	98.12		30	97.90	97.63
37.5	98.49	98.30		45	98.10	97.86
50	98.60	98.42		75	98.33	98.13
75	98.73	98.57	98.53	112.5	98.52	98.36
100	98.82	98.67	98.63	150	98.65	98.51
167	98.96	98.83	98.80	225	98.82	98.69	98.57
250	99.07	98.95	98.91	300	98.93	98.81	98.69
333	99.14	99.03	98.99	500	99.09	98.99	98.89
500	99.22	99.12	99.09	750	99.21	99.12	99.02
667	99.27	99.18	99.15	1000	99.28	99.20	99.11
833	99.31	99.23	99.20	1500	99.37	99.30	99.21
				2000	99.43	99.36	99.28
				2500	99.47	99.41	99.33

1 BIL means basic impulse insulation level.

Note: All efficiency values are at 50 percent of nameplate rated load, determined according to the DOE Test Method for Measuring the Energy Consumption of Distribution Transformers under appendix A to this subpart K.

(3) The efficiency of a medium-voltage dry-type distribution transformer manufactured on or after April 23, 2029, shall be no less than that required for their kVA and BIL rating in the following table. Medium-voltage dry-type distribution transformers with kVA ratings not appearing in the table shall have their minimum efficiency level determined by linear interpolation of the kVA and efficiency values immediately above and below that kVA rating.

Table 10 to Paragraph (c)(3)

kVA	Single-phase			kVA	Three-phase
	BIL ¹				BIL
	20-45 kV	46-95 kV	≥96 kV		20-45 kV	46-95 kV	≥96 kV
	Efficiency (%)	Efficiency (%)	Efficiency (%)		Efficiency (%)	Efficiency (%)	Efficiency (%)
15	98.29	98.07		15	97.75	97.46
25	98.50	98.31		30	98.11	97.87
37.5	98.64	98.47		45	98.29	98.07
50	98.74	98.58		75	98.50	98.32
75	98.86	98.71	98.68	112.5	98.67	98.52
100	98.94	98.80	98.77	150	98.79	98.66
167	99.06	98.95	98.92	225	98.94	98.82	98.71
250	99.16	99.06	99.02	300	99.04	98.93	98.82
333	99.23	99.13	99.09	500	99.18	99.09	99.00
500	99.30	99.21	99.18	750	99.29	99.21	99.12
667	99.34	99.26	99.24	1000	99.35	99.28	99.20
833	99.38	99.31	99.28	1500	99.43	99.37	99.29
				2000	99.49	99.42	99.35
				2500	99.52	99.47	99.40
				3750	99.50	99.44	99.40
				5000	99.48	99.43	99.39

1 BIL means basic impulse insulation level/

(d) Mining Distribution Transformers. [Reserved]

(e) Severability. The provisions of paragraphs (a) through (d) of this section are separate and severable from one another. Should a court of competent jurisdiction hold any provision(s) of this section to be stayed or invalid, such action shall not affect any other provision of this section.

[78 FR 23433, Apr. 18, 2013, as amended at 86 FR 51252, Sept. 14, 2021; 89 FR 30040, Apr. 22, 2024]