We at SVT have an extensive product range of Dry Type Transformers, from range of 25 KVA to 2000 KVA up to 33 KV voltage. Dry type transformers are voltage changing (Step-up or Step-down) or isolation device that is air cooled rather than liquid cooled. The transformer case is ventilated to allow air to flow and cool the coil (coils). Dry-type transformers can have their windings insulated various ways. A basic method is to preheat the conductor coils and then, when heated, dip them in varnish at a high temperature. The coils are then baked to cure the varnish. This process is an open-wound method and helps ensure penetration of the varnish. Cooling ducts in the windings provide an efficient and economical way to remove the heat produced by the electrical losses of the transformer by allowing air to flow through the duct openings. The dry type transformer does not require a liquid such as oil or silicone or any other liquid to cool the electrical core and coils. We adhere to IS 2026 and BEE Standards
Dry type Transformers – Classes of insulation
Dry-type transformers are available in three general classes of insulation. The main features of insulation are to provide dielectric strength and to be able to withstand certain thermal limits. Insulation classes are:
- 220°C (Class R).
- 180°C (Class H),
- 155°C (Class F).
- 130°C (Class B).
- 105°C (Class A).
Features and Benefits
- Dry Type transformers use air as the cooling medium
- The insulation used in dry type transformers is designed to withstand higher temperatures
Dry type transformers are most suitable in locations where conventional oil filled transformers present a safety hazard. Some of the locations where dry type transformers are best suited are Oil refinery, Chemical plants, Marine applications, Metro railways where significant safety is required against fire.