Electrical – the *interrupting rating* of a GFCI receptacle


Say, we have a UL943 compliant 15A GFCI receptacle on a garden-variety 15A grounded branch circuit. Some nitwit comes along and wirenuts the receptacle's load-side hot to the branch circuit ground, creating a bolted ground fault. When the power comes back on — both the breaker and the GFCI are going to race to trip on what they both detect as faults.

If the GFCI "wins the race" and trips before the breaker does, how much fault current can it safely interrupt?

Best Answer

I checked a few GFCI data sheets and they all listed either a 10kA Short Circuit Current Rating or Max Interrupting Capacity.

I'm assuming that this is similar to the 10kA rating on common household circuit breakers where the device is required to break at least 10kA.

Cooper Industries has a PDF that describes short-circuit current ratings in more deail:

Article 100 Definitions
Short-Circuit Current Rating. The prospective
symmetrical fault current at a nominal voltage to which an
apparatus or system is able to be connected without
sustaining damage exceeding defined acceptance criteria.