Question 122Electricity & Electronics - 1st Asst/Chief

70% to pass

Which of the following statements represents the reading display of a hand-cranked megohmmeter when testing a capacitor start motor start capacitor in good condition that has been properly discharged prior to the test?

AThe needle should immediately deflect to a very low resistance value and then gradually increase to infinity while cranking.
BThe needle should immediately deflect to a very low resistance value and remain there while cranking.
CThe needle should immediately deflect to infinity and remain there while cranking
DThe needle should immediately deflect to infinity and then continuously drop until a very low resistance value is indicated while cranking.
AI Explanation

The correct answer is A) The needle should immediately deflect to a very low resistance value and then gradually increase to infinity while cranking. This is correct because a capacitor start motor start capacitor in good condition that has been properly discharged prior to testing will initially show a very low resistance value, indicating the capacitor is charged. As the megohmmeter is cranked, the needle will gradually increase to an infinite resistance value, indicating the capacitor has fully discharged. The other options are incorrect because: B) would indicate a short circuit, C) would indicate an open circuit, and D) would not accurately reflect the gradual discharge of a properly functioning capacitor.

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