How to select the breaking capacity of box circuit breaker?

The breaking capacity of box Type breaker refers to the short-circuit current that can be broken by the circuit breaker on the premise of ensuring no damage in case of short-circuit fault in the circuit system. Breaking capacity is also a judgment on the protection performance of frame circuit breaker. How to select the breaking capacity of circuit breaker? Is the bigger the better? Let’s analyze it
The function of box circuit breaker is to connect, carry and disconnect normal current. At the same time, it can also connect, carry and disconnect fault current under abnormal conditions (overload and short circuit). The ability to disconnect fault current is an important standard to judge the performance of circuit breaker, that is, the breaking capacity of circuit breaker. At present, the breaking capacity of circuit breaker has two indexes, namely:
1. Rated operating short-circuit breaking capacity ics of box circuit breaker: the rated operating short-circuit current that the manufacturer can break under the specified conditions under the corresponding rated voltage. Specifically, after the circuit breaker can cut off the short-circuit current, the circuit breaker can still be used normally.
2. Rated limit short-circuit breaking capacity ICU: the limit short-circuit current that the frame circuit breaker manufacturer can break under the specified conditions under the corresponding rated voltage. That is, after the circuit breaker disconnects the short-circuit current, if it is opened and closed again, it can no longer be used normally.
The breaking capacity of box circuit breaker has many different specifications and parameters. Generally speaking, the greater the breaking capacity, the higher the safety, but the price of circuit breaker with large breaking capacity will be higher. Therefore, it is necessary to select a circuit breaker with relatively appropriate breaking capacity on the premise of ensuring equipment safety, so as to save a certain budget.


Post time: Nov-30-2021