Question 52Electricity/Electronics - Assistant Engineer70% 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?
AI Explanation
The correct answer is A) an autoranging digital multimeter.
An autoranging digital multimeter is the most reliable device to verify that a circuit is actually dead. It can accurately measure the voltage level in the circuit and confirm that there is no voltage present, indicating the circuit is de-energized. This is the most certain way to verify the circuit is safe for electrical work, as required by electrical safety regulations.
The other options are less reliable. A solenoid tester (B) can provide false positives if the tester is improperly grounded. Non-autoranging multimeters (C) may not have the necessary sensitivity to detect low voltage levels. A non-contact voltage tester (D) can be affected by nearby electrical fields and may not definitively confirm the circuit is completely de-energized.
Related Questions
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