What electrical tests for motor maintenance?

[wvjohn]

We have several 2300/2400 volt induction motors operating fans and pumps. What would be a good battery of tests to perform on a regular basis as preventive/predictive maintenance. We would like to start keeping better records and also be able to predict problems and take the motors out of service if the tests so indicate. We have the capability to perform megger, DLRO, and DC Hi-pot tests. Are there other tests that we should be using? What are some test voltages we should use and also what would be good test results? Thank you in advance for your time and information.

WV John

 

[majedi]

dear sir
the following tests are recommened:
1-polarization index test for checking the dryness of stator windings.
2-check cold D.C resistance for stator winding
3-check the quality of the bearings &greases used .
4-check the dirtness of the windings,clean and dry if needed
5-check current balances for each phases.
6-test results and voltages please follow iec or ieee standards.

 

[DougMSOE]

Strongly recommend a phase to phase and phase to ground insulation power factor test. This will replace the dc high pot and the megger. Insulation PF can be tracked easily to the point of failure. Not so with the other 2.
A DLRO is of no value due to the way the stator winding is made up even if it is a delta type.
Winding temperature by winding resistance or by RTD/TC is manditory, and correct to 40 C. The equation/curve is in IEEE.
Everything else is good.

 

[busbar]

One reference is §7.15.1 of NETA 2001 Maintenance Testing Specifications for Electrical Power Distribution Equipment and Systems, described at netaworld.org.

 

[jbartos]

Suggestion: Visit

http://www.manufacturing.net/ctl/index.asp?layout=articleWebzine&articleid=CA220719#04

for: Software "MotorMD"

 

[Steventyj]

I can't say whether the information on this site is good or not but you may find it helpful.

http://www.aepproserv.com/Documents/Proposed_Motor_Predictive_Maintenance_Program.pdf

Also I would recommend spending time to organize how you are going to track your motors and their maintenance/failures. Do you currently track any other motors in your plant? If not then it will be nice to be able to start from scratch and set up your records so that it will work best for you.

- Steven

 

[kuwait]

Dear dougMSOE,
Could you please clarify Insulation power factor and its test set up.