Testing & TroubleshootingQuestion 520 of 521
During commissioning of a new bathroom circuit, how should you verify a GFCI receptacle provides ground-fault protection?
a.Press the built-in TEST button (and/or use a GFCI tester) and confirm it trips and removes power, then RESET
b.Measure 120 V hot-to-neutral only and assume it works
c.Check that the LED is lit and skip tripping it
d.Short the hot to ground with a screwdriver to force a trip
Explanation
The correct functional test is to operate the built-in TEST button (or an external GFCI tester that injects a small fault) and confirm the device trips and de-energizes the outlet, then reset it. A normal voltage reading (b) or a lit indicator (c) does not prove the ground-fault sensing works. Deliberately shorting to ground (d) is dangerous and unnecessary.
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