DC Moulded Case Circuit Breaker

How do DC circuit breakers work?

DC circuit breakers work in the same way as AC circuit breakers, with thermal and magnetic protection. The thermal protection trips the breaker when the current exceeds the rated value. When the current generates more heat, the bimetallic contacts heat up and expand.

Why use a DC circuit breaker?

DC power is used because it allows a battery pack to provide closing/tripping power to the circuit breaker control circuit in the event of complete AC power failure. This operating mechanism has the advantages of high reliability, low failure rates, long maintenance intervals and low maintenance effort.

Are DC circuit breakers placed on the positive or negative terminal?

For DC circuits, the overcurrent protection is always placed on the positive pole. The circuit protection should be connected to the mains as far as possible.