Introduction
SFM3 series molded case circuit breaker (hereinafter referred to as “circuit breaker”) is suitable for infrequent transfer and infrequent starting of motor in circuits with AC 50/60Hz, rated insulation voltage up to 1,000V, rated working voltage up to 415/690V and rated working current up to 800A (Inm≤400A and below). The circuit breaker has the overload and short-circuit protection functions, and can protect the circuit and power equipment from damage. The circuit breaker has the features of small dimension, high breaking capacity, short arc, vibration resistance etc.