What is the minimum standard for the interrupting capacity of circuit breakers?

The minimum standard for the interrupting capacity of circuit breakers is that it must meet or exceed the maximum fault current calculated for the system. This is essential because the primary function of a circuit breaker is to protect the circuit by disconnecting it during a fault condition. If the interrupting capacity of a circuit breaker is less than the maximum fault current, the device may not be able to open the circuit effectively, potentially leading to equipment damage, fire hazards, or safety risks for personnel.

When designing electrical systems, engineers calculate the maximum fault current to ensure that the circuit breakers are appropriately rated. This rating ensures that when a fault occurs, the circuit breaker can safely interrupt the current flow without sustaining damage or failing to operate. It guarantees the reliability and effectiveness of the overcurrent protection mechanism in the electrical system.