What is the breaking capacity of 400a MCCB?

The breaking capacity of a 400A MCCB (Molded Case Circuit Breaker) is the maximum current level that the circuit breaker is capable of interrupting safely without causing damage to the electrical system or equipment. The breaking capacity is typically expressed in terms of both the interrupting current rating and the short-circuit current rating.

The interrupting current rating refers to the maximum level of fault current that the MCCB can safely interrupt when it is tripped. The interrupting current rating of a 400A MCCB can vary depending on the manufacturer and specific model, but it is typically between 10,000 and 100,000 amperes.

The short-circuit current rating refers to the maximum level of short-circuit current that the MCCB can safely withstand without damaging its internal components. The short-circuit current rating of a 400A MCCB is typically around 22,000 amperes.

It's important to note that the breaking capacity of a 400A MCCB should match the requirements of the electrical system, and it should be properly selected and installed by a qualified electrician to ensure safe and reliable operation. Additionally, regular maintenance and testing can help ensure that the MCCB continues to perform as intended.