DC contactor is mainly used for remotely connecting and disconnecting the DC circuit, as well as frequently starting, stopping, reversing and plug braking the DC motors. It's also widely used for connecting and disconnecting the lifting electromagnet, solenoid valve, clutch's magnetic coils. DC contactor has two structure of stereoscopic arrangement and plane arrangement, some products are derived on the basis of AC contactor. Therefore, structure and working principle of the DC contactor are basically the same as that of AC contactor, which mainly consists of three parts, electromagnetic mechanism, contact system and arc-extinguishing equipment.