Essentially, the explosion-proof starter is an electrical device used to control the starting, stopping, and operation of the motor.

When the operator presses the start button, the start signal is transmitted to the internal control circuit. The control circuit is usually composed of elements such as contactors and relays. When the coil of the contactor is energized, the main contact of the contactor closes, thereby connecting the power supply to the motor and enabling the motor to start running.

During the motor's operation, the thermal relay monitors the current of the motor. If the motor is overloaded and the current exceeds the set value of the thermal relay, the bimetallic strip of the thermal relay deforms due to heating, triggering the opening of its normally closed contact. This will cause the coil of the contactor to lose power, and the main contact of the contactor to open, thereby cutting off the motor's power supply to achieve overload protection and prevent the motor from being damaged or causing danger due to overload.

If the voltage in the power grid drops or there is a voltage loss, the electromagnetic attraction of the contactor coil is insufficient. The main contact of the contactor automatically opens under the action of the spring, and the motor stops running, achieving voltage loss protection.

In the explosion-proof starter, in order to meet the explosion-proof requirements, its shell adopts a special explosion-proof structure and materials, which can withstand the possible sparks, arcs, and explosion pressure generated inside, and prevent the internal sparks and high temperature from being transmitted to the external explosive environment to avoid causing an explosion accident.

In conclusion, the explosion-proof starter realizes the starting and stopping control of the motor through the control circuit. At the same time, it has protection functions such as overload, phase loss, and voltage loss, and its explosion-proof shell can ensure safe use in an explosive environment.