Dry Type Transformer

Most manufacturers of dry-type transformers make the same unit over and over. As if they were making cookies rather than an engineered product. You as the customer end up taking what you can and planning your installation around the transformer. At Virginia Transformer Corp (VTC) we think you should get what you NEED. That is why we custom design and manufacture a full range of dry-type transformers up to 20 MVA, 34.5 kV for all applications: industrial, commercial, institutional, indoor, outdoor, power distribution, drive/rectifier, even for heavy-duty traction. VTC's commitment is to satisfy each customer's individual needs with a high-quality, custom designed transformer while maintaining the shortest lead-times in the industry. With over 35 years of design experience applied in over 150,000 square feet of ISO-9000 certified manufacturing environment, we can easily meet a variety of diverse requirements: Drive & harmonic loads, overloads of up to 450%, multiple motor starts, and of course lighting and heating. In fact, our dry-type transformers up to 3000 kVA, 15 kV class are UL® rated.

In order to provide for the stringent requirements of different applications, our engineers look at all the various parameters and work with our customers to determine the best features: Coil shape, winding type, conductor material, impedance, K-factor, core type, enclosure and especially coil processing. Custom designed transformers achieve the highest rated efficiency level for a given set of conditions
Why choose Dry? Often a liquid-filled transformer is specified for a project when a dry-type transformer is best suited for the application. We provide the technology to offer dry-type alternative solutions that may greatly benefit your organization.

Reduce your costs. Because our dry-type transformer can be located closer to the electrical load than liquid transformers, we reduce the length of costly low voltage cabling. Dry-type weigh less than equivalent liquid-filled transformers so installation and craning costs are reduced. Downtime for maintenance and inspection is reduced and there are no annual fluid testing or gasket replacements.

Safer for workers and the environment. These units are non-flammable and self-extinguishing and pose less risk of fire due to materials used in construction. Units require no drainage areas or retaining walls since there is no risk of oil leaks or ground water contamination.

Quality all around. Our shorter lead times - as little as eight weeks from time of order - help meet your most critical schedule needs. We also offer a wide variety of termination arrangements to match every major switchgear manufacturer in the U.S.
  • Subway & rapid transit

  • Hospitals, hotels & schools

  • Utilities & power plants

  • Chemical plants

  • Mining operations

  • Paper & steel mills

  • Oil & gas refineries

  • Office & shopping complexes

  • Manufacturing plants

  • Airport Terminals

  • Water treatment plants

  • Research facilities

Range - Up to 20 MVA, 35 kV voltage class, 150 kV BIL
Loading - Designed to deliver rated current and MVA in all tap positions
Service - Indoor or outdoor
Basic Impulse Level (BIL) - Per ANSI standard
Impedance - See chart at right
Coils - Aluminum or copper conductor, circular or rectangular construction, disc or barrel wound
Coil Sealing - Vacuum Pressure Impregnated (VPI)
Insulation - 220c Insulation system
Enclosure - NEMA 1, Complete breakdown Crowned roof for water shedding, base suitable for lifting, jacking and skidding
Paint - ANSI 61 enamel on phosphatized cleansed surface
Nameplate - Engraved stainless steel for outdoor use, metalized Mylar adhesive for indoor application

Routine in-house tests per ANSI C57.12.91 include:

  • Ratio

  • Polarity & Phase Relation

  • Resistance Measurement

  • Excitation Current & No-Load Loss

  • Impedance & Load Loss

  • Applied Potential

  • Induced Potential

  • Partial Discharge

Witness testing is offered and arranged according to your schedule
12/18 month standard warranty


Spec Sheet
Weights and Dimensions
BIL Standard
Standard Ratings
Audible Sound Standard
Installation & Operation Manual

VTC's commitment doesn't stop once the manufacturing process ends. We are just as focused on meeting our customer's needs during shipping, installation and follow-up services. VTC offers total commissioning and testing services, from unloading and installation, to maintenance contracts to keep your unit running as well as the first day it was energized.