ASHRAE-90.1-2022- - Page 148
Extracted Content
Table 8.4.4 Minimum Nominal Efficiency Levels for Low-Voltage Dry-Type Distribution Transformers [ a,b]
| Single-Phase Transformers | Col2 | Three-Phase Transformers | Col4 |
|---|---|---|---|
| kVA c | Efficiency,% d | kVA c | Efficiency,% d |
| 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. A low-voltage dry-type distribution transformer is a transformer that is air-cooled, does not use oil as a coolant, has an input voltage 600 V, and is rated
for operation at a frequency of 60 Hz. b. A low-voltage dry-type distribution transformer with a kVA rating not listed in the table shall have its minimum efficiency level determined by linear
interpolation of the kVA and efficiency values listed in the table immediately above and below its kVA rating. Extrapolation shall not be used below the minimum values or above the maximum values shown for single-phase transformers and three-phase transformers . b. Kilovolt-ampere rating. c. Nominal efficiencies shall be established in accordance with the 10 CFR 431.193 test procedure for low-voltage dry-type distribution transformers .
- Transformers with tap range of 20% or more.
- Drive (isolation) transformer .
- Rectifier transformer .
- Auto- transformer .
- Uninterruptible power supply transformer .
- Special impedance transformer .
- Regulating transformer .
- Sealed and nonventilating transformer .
- Machine-tool (control) transformer .
- Welding transformer .
- Grounding transformer .
- Testing transformer .
- Nonventilated transformer.
8.5 Prescriptive Path (Not Used)
8.6 Alternative Compliance Path 8.6.1 Computer Room Systems. Power distribution systems and equipment only serving a computer room with IT equipment load greater than 10 kW shall comply with ASHRAE Standard 90.4, Energy Stan- dard for Data Centers.
8.7 Submittals 8.7.1 General. Compliance documentation and supplemental information shall be submitted in accordance with Section 4.2.2 of this standard.
8.7.2 Permit Application Documentation (Not Used) 8.7.3 Completion Requirements 8.7.3.1 Record Documents. Construction documents shall require that within 90 days after the date of system acceptance, record documents shall be provided to the property owner, including
a. a single-line diagram of the property electrical distribution system, b. floor plans indicating location and area served for all distribution, and c. site plans indicating location and area served for all distribution.
146 ANSI/ASHRAE/IES Standard 90.1-2022 (I-P)