In the era of fixed line telephones, each household's telephone was powered by the telecommunications bureau. Due to the long distance between the telecommunications office and the telephone in the home, in order to ensure a certain service range, the power supply voltage of the central office switc

The 220vdc power supply is designed for switching devices and protection relays in the Thermal Power Plant, such as terminal circuit breakers, 10kV circuit breakers, generator/transformer/10kV equipment protection relays,etc.These critical DC power supply systems are also designed with redundancy fe