Question 289Electricity/Electronics - QMED70% to pass
In using a portable growler for the purpose of locating a shorted stator coil in an AC motor as shown in the illustration, what statement is true as the feeler is moved from slot to slot around the stator? Illustration EL-0200
AI Explanation
The correct answer is D.
The feeler will vibrate in synchronism with the 60 Hz AC power source and produce a growling noise when the feeler is moved over a slot containing a shorted coil. This is because a shorted stator coil creates a localized magnetic field that interacts with the alternating current in the feeler, causing it to vibrate and produce a distinctive growling noise.
The other options are incorrect because:
A) The vibration and noise occur when the feeler is over a shorted coil, not a non-shorted coil.
B) An open coil would not produce the same effect as a shorted coil.
C) The feeler does not remain motionless when over a shorted coil, but rather vibrates and produces a growling noise.
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