How is controlling torque generated in a megger______________?
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Answer: C. coil
Explanation
Meggers utilize special internal coil configurations to generate controlling and restoring torques. Crossed-coil mechanisms eliminate the need for traditional mechanical hairsprings in insulation testers. This internal coil arrangement ensures reliable resistance readings regardless of generator cranking speed. Meggers are high-resistance measuring instruments equipped with hand-cranked DC generators. Controlling torque opposes the deflecting torque to stabilize the indicator pointer at a reading. Insulation testing requires portable instruments that function reliably in remote field environments.
Electricians test building wiring and motor windings for insulation breakdown using megohmmeters. Preventing electrical fires requires verifying that wire insulation can withstand high voltage stresses. Rugged internal mechanical design ensures testing instruments survive harsh construction site conditions. Traditional springs provide control torque in benchtop instruments but are omitted in hand-cranked meggers. Gravity control requires instruments to remain level and is unsuitable for portable handheld meggers. Eddy currents provide damping torque to stop oscillations rather than generating controlling torque.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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