Question 46Electricity & Electronics - QMED

70% to pass

Before electrical work can be safely undertaken, the equipment must be de-energized, locked and tagged out, and verification must be made that the circuit is actually dead. What testing device is most certain to reliably verify that a circuit is actually dead?

Aa non-contact voltage tester
Ban autoranging digital multimeter
Ca solenoid type voltage tester
Da non-autoranging digital multimeter
AI Explanation

The correct answer is B) an autoranging digital multimeter. An autoranging digital multimeter is the most reliable device to verify that a circuit is actually dead because it can accurately measure the voltage in the circuit and confirm there is no voltage present. This ensures the circuit has been properly de-energized before any work is performed, in accordance with electrical safety regulations. The other options are less reliable - a non-contact voltage tester may not detect low voltages, a solenoid type voltage tester can be affected by electromagnetic fields, and a non-autoranging digital multimeter requires the user to manually select the correct voltage range, which increases the risk of an incorrect reading.

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