Troubleshooting AC motors and starters:Measurements used for a motor

The following are the measurements used for a motor:

• Temperature: Thermocouples/Resistance elements/thermistors measure temp- eratures of windings, bearings, etc.

• Voltage and current: Volts and Amps are measured using portable voltmeter,

recording voltmeter, Ammeters – clamp type, recording, CRO, etc.

• Insulation resistance: Meggers – hand/motor-operated.

• Winding resistance: Kelvin bridge, wheatstone bridge, resistance meters, etc.

• Vibration: Vibration metering, monitoring, and analyzing equipment.

• Speed: Stroboscopes, tachometer, etc.

• Dielectric loss angle measurement: Tan–delta measurement.