Thermal relay phase failure protection function

Some types of thermal relay also has the function of phase failure protection.

The phase interruption protection function of the thermal relay is provided by a differential amplification mechanism composed of an inner and an outer push rods. When the motor is working normally, the current of the thermal relay is normal, and the inside and outside two push rods move forward to the appropriate position. When there is a power supply phase disconnection caused by phase, the phase current is zero, the double sheet metal cooling to reset, the push rod in the right move, the other two for bimetal current is increased and the bending degree increases, the push rod moves to the left, due to differential amplification, in promoting often close contact to open phase faults within a very short time after the release of AC contactor, motor power parking and protection. Relay manufacturers