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toll free 800.334.5214 ACME ELECTRIC |
hubbell-acmeelectric.comM e d i u m V o l t a g e T r a n s f o r m e r s
Coil Construction
Coils are wound with aluminum conductor and insulated with UL recognized Class 220º C materials such as DuPont Nomex®.
Continuous Wound Coil
The continuous layer wound coil consists of columns of rectangular magnet wire layers separated by axial cooling ducts inserted
between various layers. This gives the coil a single column mass and maximum mechanical axial strength. Coils are also kept as
round and tight as possible in order to provide maximum strength against radial short circuit
forces.
The air ducts provide adequate air space between layers and coils, eliminating the need for flash barriers, which can restrict cool-
ing air flow, increasing hot spot temperatures. During assembly, high voltage windings are positioned over low voltage windings to
minimize axial stresses under short-circuit conditions.
All coils are preheated to drive out moisture, and then impregnated with high quality polyester resin to eliminate air-filled voids that
can promote corona. This also reduces effective spacing necessary to maintain a high BIL.
Cores
Transformer cores are manufactured with grain oriented cold rolled high purity silicon steel having the highest possible silicon con-
tent compatible with magnetic steel production methods. All core steel has been annealed to relieve stresses and to assure
flatness and optimum magnetic properties after slitting and processing.
Coil Taps
Coil taps are furnished in the high voltage winding to compensate for variations in the incoming supply voltage to the transformer.
All Acme Electric medium voltage transformers are equipped with 2–2½% ANFC (Above Normal Full Capacity) and 2–2½% BNFC
(Below Normal Full Capacity) high voltage taps that are easily accessible through removable panels on the front of the transformer.
Further, we are structured to provide custom specifications. If you need a medium voltage dry-type transformer with specifications
different from those in our existing line, our engineers can design one for you. For assistance, contact your Acme representative or
call 1-800-334-5214 for assistance in developing a solution to your needs.
Features
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Completely encased in a ventilated steel enclosure with no exposed live parts
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Air-cooled by natural convection
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Smaller, easier to maintain than liquid-filled transformers
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No additional fireproofing or venting needed
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Long life expectancy
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Covered under ACME’s 3 year warranty
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Available with 3R Weathershield
Applications
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Residential applications
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Hospitals, clinics and other health care operations
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Educational facilities
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Office buildings
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Theaters, stadiums and other entertainment venues