Question 511Electricity & Electronics - Assistant Engineer

The correct answer is C) The live-line tester should be checked by connecting to a known high voltage source before and after the circuit to be worked upon is tested. This is the correct answer because it is important to verify the proper functioning of the live-line tester both before and after testing the circuit. Connecting the tester to a known high voltage source ensures that it can accurately detect the presence of voltage, which is crucial for ensuring the circuit is truly de-energized and safe to work on. Checking the tester only before or only after testing the circuit would not provide the necessary verification. The other options are incorrect because option A) only requires checking the tester before the circuit is tested, and option B) only requires checking the tester after the circuit is tested, both of which do not fully ensure the tester's functionality throughout the testing process. Option D) is incorrect because it is essential to verify the tester's ability to detect voltage, regardless of whether it has been declared inoperative.