Question 214Electricity/Electronics - Assistant Engineer70% to pass
As shown in the illustrated diagnostic setup for locating a shorted field coil of a ten- pole synchronous motor, if 240 VAC/60 Hz is applied across the brushes, what would be the individual voltage drops measured across each field coil assuming that none of the field coils are shorted? Illustration EL-0202
AI Explanation
The correct answer is C) 24 VAC.
In a ten-pole synchronous motor, the field coils are connected in series. With 240 VAC/60 Hz applied across the brushes, the voltage drop across each individual field coil would be 24 VAC. This is because the total voltage is divided equally among the ten field coils, resulting in a 24 VAC drop across each coil.
The other options are incorrect because they do not accurately represent the voltage drop across each individual field coil in a ten-pole synchronous motor configuration. Option A (6 VAC) is too low, Option B (12 VAC) is too low, and Option D (48 VAC) is too high.
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