Power should be turned off at the __________ ONLY.

Power should be turned off at the __________ ONLY.

• A. Main Panel
• B. Local Switch
• C. Breaker Box
• D. Outlet

Answer: (A)

The main idea is that true de-energization comes from cutting power at the main service disconnect, which is located in the main panel. A local switch only interrupts power to a single device or branch circuit, so other parts of the system can remain energized. A breaker box contains individual breakers, and turning off one breaker stops power to that circuit but doesn’t shut down everything unless the main disconnect is opened. An outlet only powers that receptacle and does not affect the rest of the wiring. Therefore, to ensure complete safety and isolation, power should be turned off at the main panel. After doing so, verify zero voltage with a tester and follow appropriate safety procedures.

The main idea is that true de-energization comes from cutting power at the main service disconnect, which is located in the main panel. A local switch only interrupts power to a single device or branch circuit, so other parts of the system can remain energized. A breaker box contains individual breakers, and turning off one breaker stops power to that circuit but doesn’t shut down everything unless the main disconnect is opened. An outlet only powers that receptacle and does not affect the rest of the wiring. Therefore, to ensure complete safety and isolation, power should be turned off at the main panel. After doing so, verify zero voltage with a tester and follow appropriate safety procedures.