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G e n e r a l Specifications
222 toll free 800.334.5214 ACME ELECTRIC |
151 - 300 kVA 55 db*
301 - 500 kVA 60 db*
* Sound levels are based on transformers with a K-Factor of 4 and a temperature rise of 150 degrees centigrade.
Enclosed, ventilated transformers must incorporate vibration dampening pads in their construction, located between
the transformer core and coil assembly and the transformer case. External vibration dampening pads will not be used
on enclosed, ventilated designs as they tend to increase audible noise. Transformers 15 kVA and larger shall be floor
mounted on a concrete pad. All connections to the transformer will be made by means of flexible metallic conduit.
1.0.7 Transformers shall incorporate a neutral conductor sized at 2 times rated phase current. Transformer
cases shall be grounded per the National Electric Code.
1.0.8 Transformers shall be 60 Hz, 480 or 600 volts delta primary, 208Y/120 volt secondary. kVA rating as
indicated. Contractor to provide all necessary lugs for all transformers. Transformer enclosures shall be Type 2 and UL-3R
listed with the addition of a weather shield.
1.0.9 Complete shop drawings must be submitted for approval on all dry type transformers.
1.0.10 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 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.
1.0.11 Warranty: Transformers must be warranted against defects in materials, workmanship and performance for ten years from
date of manufacture.
SPECIFICATION GUIDE FOR DRIVE ISOLATION® TRANSFORMERS
1.0 Dry Type Transformers:
1.0.0 The following information should be utilized only by trained technical personnel. If you need assistance, please contact Acme’s
Technical Services Department at 800-334-5214.
1.0.1 Provide dry type, enclosed, epoxy encapsulated transformers as indicated and specified herein. Transformers shall be designed
for use with AC/DC Drive applications and labeled as such.
1.0.2 Transformers shall be designed, constructed and rated in accordance with UL, CSA, NEMA, ANSI, IEEE, and OSHA standards.
1.0.3 Transformers 7.5 - 20 kVA shall be three phase,
compound filled, incorporating a 180 degree C insulation system and designed not to exceed a 115 degree C temperature rise
above a 40 degree C ambient under full load conditions. Taps are provided on the primary side of the transformer as follows:
(a) 1-5% above normal full capacity.
(b) 1-5% below normal full capacity.
Transformers 27 - 750 kVA shall be the ventilated type, incorporating a 220 degree C insulation system and designed not to
exceed a 150 degree C temperature rise above a 40 degree C maximum ambient under full load conditions. Taps are to be pro-
vided on the primary side of the transformer as follows:
(a) 2 - 2.5% above normal full capacity.
(b) 2 - 2.5% below normal full capacity.
Alternate 1: 115 degree C rise transformers shall incorporate a 220 degree C insulation system and be designed not to exceed a
115 degree C temperature rise above a 40 degree C maximum ambient under full load conditions.
Alternate 2: 80 degree C rise transformers shall incorporate a 220 degree C insulation system and be designed not to exceed 80