H Class no -encapsulated-winding dr y-type power transformers with compound cross section designed by both Shenyang Transformer Research Institute get breakthrough magnetic-circuit structure and entire layout of traditional transformers. reach international advanced level. Meanwhile, it seizes the visual advantages on the aspect of energy saving and environmental protection. This product shows balance of three-phase no-load current, less no-load loss and no-load current that are a 40% and a 80% decline respectively compared with national standard, besides, it is featured with smaller volume, lighter weight and lower noise, therefore, this product is more and more popular with customers. It is used extensively in the locations where require fireproof and explosion-proof functions, such as high -rise building, shopping center, airport, underground, station, port, petrol, chemistry engineering, nuclear power station, nuclear submarine residential area, light rail, power plant and so on.