There are various technologies that can test a motor while running, including:
- Ultra sound (UT)
- PdMA On-line, MCE EP1000/EXP4000
- Dranetz - On-line continuous motor
Curious on how often you should test?
On-line testing with motor relays is a continuous 24/7 device.
Off-line testing frequency will depend on the atmosphere the equipment is in. It can be done more often if tracking a deterioration situation.
- Air conditioning -1 X a year
- Typical seasonal conditions (humid in summer/dry in winter) - 2 X a year
How do we know when the stator is going to fail? To find out what is going on with the stator, Decatur Industrial offers offline condition monitoring which does resistance to ground, phase to phase resistance, and polarization index.