400kVA S20 10kv Oil Immersed Transformer Mining Site Power Transformation

Dry transformers use epoxy resin to insulate windings without insulating oil; oil-immersed transformers rely on mineral oil for insulation and heat dissipation. Choose dry-type for indoor buildings, shopping malls, hospitals, high-rise residential, underground substations, fire-sensitive areas, and places with strict environmental protection requirements. Choose oil-immersed for outdoor box substations, large industrial parks, power grid main substations, open air sites with sufficient ventilati

Dry-type transformers are far safer in fire prevention. They have no flammable insulating oil, low fire risk, self-extinguishing epoxy material, and will not leak combustible liquid. Oil-immersed transformers contain a large volume of flammable oil; oil leakage, overheating or short circuit may trigger fire and explosion, requiring dedicated fire isolation walls, oil pits and fire extinguishing facilities.

Dry-type transformers can be directly installed indoors in power distribution rooms without independent fire isolation zones, only needing ventilation for heat dissipation. Oil-immersed transformers must be placed in separate outdoor bays or dedicated oil-resistant transformer rooms, equipped with oil collection pits, fire baffles and oil interceptors, occupying much larger construction space.

Dry-type transformers produce slightly higher operating noise than oil-immersed ones. For pollution: Dry-type has zero liquid leakage risk, no oil waste, no soil/water contamination. Oil-immersed has leakage risks; leaked oil pollutes soil and underground water, and waste oil needs qualified hazardous waste treatment, which brings environmental compliance pressure.

Standard cast resin dry transformers cannot be directly exposed to rain, snow and strong humidity outdoors; they need IP54/IP65 protective cabinets. Oil-immersed transformers are designed for outdoor use and can work under open air with simple rainproof covers; installing oil transformers indoors requires strict fire and oil containment facilities, which is rarely adopted by customers due to high construction cost.