EXCEPTION: | The following transformers are exempt: 1. Transformers that meet the Energy Policy Act of 2005 exclusions based on the DOE 10 C.F.R. 431 definition of special purpose applications. 2. Transformers that meet the Energy Policy Act of 2005 exclusions that are not to be used in general purpose applications based on information provided in DOE 10 C.F.R. 431. 3. Transformers that meet the Energy Policy Act of 2005 exclusions with multiple voltage taps where the highest tap is not less than 20 percent more than the lowest tap. 4. Drive transformers. 5. Rectifier transformers. 6. Auto-transformers. 7. Uninterruptible power system transformers. 8. Impedance transformers. 9. Regulating transformers. 10. Sealed and nonventilating transformers. 11. Machine tool transformer. 12. Welding transformer. 13. Grounding transformer. 14. Testing transformer. |
Table C405.6
Minimum Nominal Efficiency Levels For 10 C.F.R. 431 Low Voltage Dry-Type Distribution Transformers
Single Phase Transformers | Three Phase Transformers | ||
kVAa | Efficiency (%)b | kVAa | Efficiency (%)b |
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 |
a kiloVolt-Amp rating.
b Nominal efficiencies shall be established in accordance with the DOE 10 C.F.R. 431 test procedure for low voltage dry-type transformers.
EXCEPTION: | Dwelling units in other than Group R-2 multi-family and live/work units are not required to provide a separate electrical metering at each dwelling unit where electrical usage is metered separately for each of the following building end uses: 1. Dwelling units. 2. Sleeping units. 3. Commercial kitchens. 4. Central laundries. |
Wash. Admin. Code § 51-11C-40507
Statutory Authority: RCW 19.27A.020, 19.27A.025 and chapters 19.27 and 34.05 RCW. 13-04-056, § 51-11C-40507, filed 2/1/13, effective 7/1/13.