Does third party equipment exist to test the AFCI to determine that it is functioning properly?


28 September 2021

Product Line:
Arc Fault Circuit Breakers

No. So-called AFCI testers are on the market, but they are not UL listed for testing the function of a CAFI/AFI circuit breaker. UL 1436 refers to them as "indicators" rather than testers, and Square D does not endorse them or recommend their use. They are subject to error in the form of giving a false negative result.

The UL approved method of testing an AFCI circuit breaker is to press the push-to-test button when installed in an energized load center or panel. This test injects a signal into the AFCI sensor that looks like an arc to the AFCI. A properly functioning AFCI will trip when the test button is pushed as long as the panel is energized and the neutral pigtail/plug on neutral connection is made to the neutral bar.

Paragraph 31.8.1 of the UL 1436 standard requires the AFCI indicator markings or instructions to effectively state that the test button on the AFCI circuit breaker demonstrates proper operation.