UL 508A Frequently Asked Questions

Q. To increase SCCR rating of the panel, why would you ever want to use anything besides a Main fused disconnect?

A. SB4.3 specifies components that can be used to limit the available short circuit current available. Current limiting fuses (SB4.3.3 part a) is one allowable method and Current limting circuit breakers are another method (SB4.3.2 part a). The advantage of a circuit breaker is that it is resetable after a fault condition, fuses would need to be replaced.

Category: Application

Keywords: increase, increaing, current limiting, fuses, circuit breaker