Question 254Electricity/Electronics - Assistant Engineer70% to pass
The motor fails to start on an attempted startup. With the start button depressed, a voltmeter reading between 1 and 5, as in figure "A" shown in the illustration, indicates line voltage available to the control circuit, what should be your next step in the troubleshooting process? Illustration EL-0007
AI Explanation
The correct answer is A) attempt to reset the overload relay and determine the cause of the overload if applicable.
The reasoning is that with a voltmeter reading between 1 and 5 volts, indicating line voltage available to the control circuit, the issue is likely related to an overload condition that has tripped the overload relay, preventing the motor from starting. The next logical step would be to reset the overload relay and investigate the cause of the overload, which could be due to a variety of factors such as a mechanical issue, a faulty component, or an overloaded circuit.
The other options are not the correct next step in the troubleshooting process. Testing the stop button for continuity (B) or ensuring the disconnect switch is closed (C) would not address the specific issue indicated by the voltmeter reading. Testing the contactor coil "M" for continuity (D) may be a subsequent step, but it is not the immediate next step in the troubleshooting process.
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