ACME ELECTRIC
•
MILWAUKEE, WI
•
800.334.5214
•
acmetransformer.com
135
GENERAL
ELECTRICAL CONNECTION DIAGRAMS
ACME
®
TR NSF RMER
™
SPECIFIC TIONS
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 and ventilated transformers
as indicated herein. Transformers shall be Acme or
approved equal.
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 rated 27 kVA and larger, single and three
phase shall be the ventilated type, incorporating a 220
degree C insulation system and designed not to
exceed 150 degree C temperature rise above a 40
degree C ambient under full load conditions. Taps are
to be provided on the primary side of the transformer
as follows:
(a)
2 - 2.5% above normal full capacity.
4 - 2.5% below normal full capacity.
-or-
(b)
2 - 2.5% above normal full capacity.
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 115 degree C temperature
rise above a 40 degree C ambient under full load
conditions. In addition, the transformer shall have
the ability to carry a continuous 15% overload without
exceeding a 150 degree C rise above ambient.
Alternate 2:
80 degree C rise Transformers shall
incorporate a 220 degree C insulation system and
be designed not to exceed 80 degree C temperature
rise above a 40 degree C ambient under full load
conditions. In addition, the transformer shall have the
ability to carry a continuous 30% overload without
exceeding a 150 degree C rise above ambient.
1.0.4
Transformer enclosure finish must be ASA 61 gray
powder polyurethane paint. Transformer enclosure
temperature shall not exceed 50 degrees C plus
the ambient under any condition of loading at any
specified temperature rise at or below 150 degrees C.
1.0.5
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.
1.0.6
Transformer shall incorporate an electrostatic shield
for the attenuation of voltage spikes, line noise, and
transients.
1.0.7
Single phase transformers and three phase
transformers terminate in copper or aluminum bus bar.
1.0.8
Transformer coils designed and manufactured 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:
30 - 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.
External vibration isolation pads will 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 Electric Code.
1.0.11
Transformers shall be dry-type 600 volt class, 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, 50, 75, and 100% load.
(f)
Regulation at 100% and 80% power factor.
(g)
Audible sound level.
(h)
Dimensions and weight.
(i)
Applied potential test.
(j)
Induced potential test.
(k)
Excitation current.
(l)
IR, IX, and IZ percentages.
(m)
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.
Specification Guide for
Dry Type Distribution Transformers
