Red Seal Appliance Service Technician Practice Exam

Name a common test for analyzing motor windings in appliances.

1. Voltage measurement

2. Current measurement

3. Resistance measurement

4. Power factor testing

The correct answer is: Resistance measurement

Resistance measurement is a common test for analyzing motor windings in appliances because it helps determine the condition of the windings. By measuring the resistance, technicians can identify issues such as short circuits, open circuits, or grounded windings. A motor with damaged windings may exhibit an abnormal resistance reading compared to its specified range. This test is straightforward and can often be performed with a multimeter. If the resistance is too low, it indicates that the windings may have shorted together; if it is too high, it may show that there is an open circuit or that the windings are damaged. Monitoring these resistance levels is crucial for ensuring the motor operates efficiently and safely. In contrast, voltage measurement is typically used to check supply voltages and not specifically the condition of the motor windings. Current measurement, while also important for diagnosing issues, does not provide a direct indication of winding integrity. Power factor testing, while useful in assessing the efficiency of a motor running under load, does not effectively isolate winding conditions during initial inspections. Thus, resistance measurement stands out as the most direct method for analyzing motor windings.