Answer / ramgan1@gmail.com

the following are the major condition monitring in motors.

running condition

1. load current, PF, RPM, voltage applied to th emotor
2. vibrations of the motor in all three directions, vertical, horizontal, axial
3. bearing vibrations( now days in one meter we can measure the both readings)

off condition

insulations resistance of the motor
winding resistance of the individual coil
inductance of the individual coil

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