Mineral Oil Filled
The oil-filled unit is the least expensive transformer, and is suitable for distribution transformer outdoors or indoors enclosed in a vault. The oil used in transformers meets all the requirements of ANSI C57.106 and ASTM D-3487, has high dielectric strength, is free from impurities, is durable and has a high flash point These features make it an excellent insulating liquid.
The silicone fluid selected for use in transformers is a clear, liquid silicone polymer (polydimethyl-siloxane) that has been specially processed to meet exacting dielectric specifications. To obtain an optimum combination of heat transfer and fire-resistant properties, the transformer silicone fluid has a viscosity of 50 centistokes at 25°C. This fluid has a minimum fire point of 300°C and oxygen index of 21. The silicone fluid that we are using meets paragraph 450-23 (Less-Flammable Liquid Insulated Transformers) of the National Electrical Code. OSHA by its Program Directive 100-68 permits the use of silicone transformers as equivalent to askarel transformers in its enforcement of the National Electrical Code. Transformer silicone fluid has suitable dielectric characteristics, is compatible with other materials used in construction of transformers and has shown good thermal stability in accelerated aging tests with transformer materials.
Environmentally Friendly Dielectric Liquid FR3
A Fire-Resistant Hydrocarbon Fluid (FRHF) dielectric coolant formulated for use in distribution transformers is available when its unique electrical, thermal and safety properties are advantageous. It is non-toxic and readily biodegradable. It is also referred to as a High Fire Point Fluid, a High Molecular Weight Hydrocarbon or a Less Flammable Dielectric Liquid. The dielectric coolant is a listed less-flammable fluid meeting the requirements of National Electrical Code section 450-23, including a minimum fire point of 300°C and the requirements of the National Electrical Code (IEEE C2-1993).
Varelen Electric Co., Ltd