GMB88-63 series moulded case circuit breaker is applicable to the circuit of AC 50/60 hz, rated insulation voltage 690V, rated operating voltage up to AC 660V, 250V rated operating current 10A-1600A for power distribution and protection of electrical equipment in case of overload, short circuit and under voltage and also for unfrequent switchover of electrical circuits under normal conditions. The MCCB rated current up to 400A can be used in motors against overload, short circuit and undervoltage.