Short Description:

The HM4 medium-voltage circuit breaker uses sulfur hexafluoride (SF6) gas as the arc-extinguishing and insulating medium. SF6 gas has smooth breaking characteristics, and when breaking current in it, there is no current chopping phenomenon and no operation overvoltage is generated. This excellent characteristic ensures that the circuit breaker has a long electrical life. Moreover, during operation, it has no impact on the equipment’s shock, dielectric level, and thermal stress. The pole column of the circuit breaker, that is, the arc-extinguishing chamber part, is a maintenance-free closed system for life. Its sealing life complies with IEC 62271-100 and CEI17-1 standards.