Question 257Electricity/Electronics - 1st Asst/Chief70% to pass
Before work may safely commence on a high voltage system, what must first be done after disconnection and isolation?
AI Explanation
The correct answer is C) The circuit must be tested and proved dead first with a live-line tester, then grounded.
This is the correct answer because it aligns with the standard safety procedures for working on high voltage electrical systems. Before a circuit can be safely grounded, it must first be tested and verified as de-energized, typically using a live-line tester. Grounding the circuit before confirming it is dead could potentially create a dangerous short circuit. By testing the circuit first, you can ensure it is safe to proceed with grounding the system before work commences.
The other options are incorrect because they either reverse the order of testing and grounding (A and B), or specify the use of an off-line tester (D), which is not the appropriate tool for this scenario involving a live, high voltage system.
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