Acme Catalog

223 / 244

Specifications G e n e r a l
223
toll free 800.334.5214 ACME ELECTRIC |
degree C temperature rise above a 40 degree C maximum ambient under full load conditions.
1.0.4 Transformer enclosure finish must be ASA 61 gray powder polyurethane paint. Ventilated transformer enclosure temperature shall
not exceed 50 degrees C plus the ambient. Compound filled transformer enclosure temperature shall not exceed 65 degrees C, plus the
ambient.
1.0.5 Compound filled transformer enclosure shall be UL/NEMA Type 3R and so marked on the transformer (7.5 - 20 kVA). No weather
shield is required. Ventilated transformer enclosure shall be UL/NEMA Type 2 and UL-3R listed with the addition of a weather
shield and shall be so marked on the transformer (27 - 750 kVA).
1.0.6 Transformers shall incorporate an electrostatic shield for the attenuation of voltage spikes, line noise, and transients.
1.0.7 Transformers up to 220 kVA shall terminate in copper bus bar or copper wire.
1.0.8 Transformer coils must be wound with aluminum strip conductors for increased insulation life, cooler operation and lower losses.
1.0.9 Transformers must operate at audible sound levels below NEMA standard ST-20. Sound levels will not exceed the following:
up to 9kVA40 db
10 - 50 kVA 45 db
51 - 150 kVA 50 db
151 - 300 kVA 55 db
301 - 500 kVA 60 db
501 - 750 kVA 65 db
Transformers must incorporate vibration isolation pads in their construction located between the transformer core and coil
assembly and the transformer case, (27 - 750 kVA).
External vibration pads should not be used as they tend to increase audible noise. Transformers shall be floor mounted on a
concrete pad. All connections to the transformer will be made by means of flexible metallic conduit.
1.0.10 Transformer enclosure shall be grounded per the National Electrical Code.
1.0.11 Transformer voltages shall be as follows:
(a) 460 Delta - 460Y/266
(b) 460 Delta - 230Y/133
(c) 575 Delta - 230Y/133
(d) 575 Delta - 460Y/266
(e) 230 Delta - 230Y/133
(f) Other
Transformer shall be 60 Hz. kVA rating as indicated. Contractor to provide all necessary lugs for all transformers.
1.0.12 Complete shop drawings must be submitted for approval on all dry type transformers.
1.0.13 Typical performance data must be submitted for approval on all transformers. Factory tests must be made in accordance
with the latest revisions of ANSI Test Code C57.12.91 for Dry Type Transformers. Performance data provided must contain,
but not be limited to:
(a) No load losses.
(b) Full load losses.
(c) Polarity and phase rotation.
(d) Impedance at reference temperature.
(e) Efficiencies at 25, 75, 50 and 100% load.
(f) Regulation at 100% and 80% power factor.
(g) Audible sound level.
(h) Insulation class and rated temperature rise.
(i) Dimensions and weight.
(j) Applied potential test.
(k) Induced potential test.
(l) Excitation current.
(m) IR, IX, and IZ percentages.
(n) Reference and ambient temperature.
1.0.14 Warranty: Transformers must be warranted against defects in materials, workmanship and performance for ten years from
date of manufacture.