YKM1 series of molded case circuit breaker (short for circuit breaker),AC50/60HZ,Current :63-800A,Voltage:400V,500V,690V,800V.. YKM1 series of molded case circuit breaker (short for circuit breaker), is the latest circuit breaker of advanced technology. The insulation voltage is 800V, (YKM1-63: 500V), used for the circuit of rated working voltage 690V and below, (YKM1-63: 400V), rated working ...