Which statement best describes the standard method to verify a GFCI's proper operation after installation?

Which statement best describes the standard method to verify a GFCI's proper operation after installation?

• A. Only visually inspect the outlet.
• B. Press the test button and use a tester to confirm proper operation.
• C. Measure insulation resistance with a megohmmeter.
• D. No testing is required.

Answer: (B)

To verify a GFCI works after installation, you actively test its protective function by using the built-in test button and then confirm with a tester. Pressing the test button simulates a ground-fault current, causing the device to trip and cut power to the receptacle. Using a tester afterward confirms that the trip actually occurs and that power is restored correctly when you press reset. This approach checks both the sensing circuitry and the mechanical trip mechanism, ensuring the GFCI will protect you in a real fault. Visual inspection alone won’t prove the protective function or trip reliability, and measuring insulation resistance with a megohmmeter isn’t relevant to confirming GFCI operation. Skipping testing isn’t acceptable, since a nonfunctional GFCI could give a false sense of protection.

To verify a GFCI works after installation, you actively test its protective function by using the built-in test button and then confirm with a tester. Pressing the test button simulates a ground-fault current, causing the device to trip and cut power to the receptacle. Using a tester afterward confirms that the trip actually occurs and that power is restored correctly when you press reset. This approach checks both the sensing circuitry and the mechanical trip mechanism, ensuring the GFCI will protect you in a real fault.

Visual inspection alone won’t prove the protective function or trip reliability, and measuring insulation resistance with a megohmmeter isn’t relevant to confirming GFCI operation. Skipping testing isn’t acceptable, since a nonfunctional GFCI could give a false sense of protection.