Question 77Electricity/Electronics - Assistant Engineer70% to pass
What would be the indication of a grounded switch or cable as measured by a megohmmeter?
AI Explanation
The correct answer is B) 'zero'.
When measuring the insulation resistance of a grounded switch or cable using a megohmmeter, the reading will indicate a 'zero' or very low resistance value. This is because a grounded circuit has a direct connection to the ground, effectively shorting out the insulation and causing the megohmmeter to read a near-zero resistance.
The other options are incorrect because: A) being unsteady in the low range is not a definitive indication of a grounded circuit, C) being unsteady in the high range is more indicative of a high-resistance or open circuit, and D) infinity would indicate a completely open or disconnected circuit, which is the opposite of a grounded condition.
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