Question 483Electricity/Electronics - QMED70% to pass
Which of the following methods should be used to test for an 'open' stator winding coil in a wye-connected AC squirrel cage induction motor?
AI Explanation
The correct answer is C) Test with an ohmmeter with the test leads across each pair of disconnected motor lead leads in succession and compare resistances.
This is the correct method because an open stator winding coil in a wye-connected AC squirrel cage induction motor will cause an imbalance in the resistance measurements between the motor leads. By testing across each pair of leads, you can identify which coil winding has an open circuit, as its resistance will be significantly higher than the other windings.
The other options are incorrect because they do not directly test for an open stator winding coil. Option A using a growler would not reliably detect an open coil, and option B testing from the shaft to the leads would not isolate the specific open winding.
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