The circuit breaker assumes the function equivalent to a fuse. It provides overcurrent protection. It doesn't jump under normal circumstances. Generally, the relay is controlled after the control signal comes, and then the contactor is controlled by the relay to realize the operation and stop of the pump. If your cooling pump turns on the circuit breaker and jumps, there must be something wrong with your circuit. You should check whether there is any open circuit that causes the motor to be out of phase.

In addition, the contactor can achieve hundreds of thousands to millions of times of suction, so don't worry about using it too much and breaking it.

The start and stop of spindle motor is realized by frequency converter without contactor, so hundreds of thousands of motors can be the same as hundreds of motors.