Help with WR Motor Recurrent Failure
Help with WR Motor Recurrent Failure
(OP)
Hope someone can give some ideas of where to look. We have a 4,000 HP GEC Alstom WR motor, 4.16 kV with liquid rheostat that has now failed twice in two weeks in the same way. The motor is driving an automobile shredder and was first commmissioned in 1998. In both failures we had two rotor leads (same rotor phase) severely overheat at the point where they attach to the collector ring assembly. The rotor windings not yet checked with a whetstone bridge but are in process of doing so. Rheostat has not been investigated yet, but suspect no problems with it. We plan to repair the motor sufficiently so that we can run it in order to record rotor current in all three phases. Any other ideas/courses of action we should be taking?
Thanks.
Thanks.





RE: Help with WR Motor Recurrent Failure
1. Power supply quality
2. Inter-turn shorts in the affected phase of the rotor winding.
3. The rotor liquid rheostat may be malfunctioning, e.g. contact resistances with liquid are somewhat off.
4. Inter-turn shorts in the stator winding(s)\
5. A bad contact at some terminal causing voltage dip
6. Etc.
RE: Help with WR Motor Recurrent Failure
RE: Help with WR Motor Recurrent Failure
Any other suggestions?
Again, thanks.
RE: Help with WR Motor Recurrent Failure
If you want to measure the WRotor current do not use the normal clamp-on ampmeter. You need to use a Hall effect type clamp on. FW Bell or Fluke.
OR as I did, use a shunt like you would use for a dc circuit.
I used this method when I worked for a consultant in the scrap industry.
I think I know who you work for since I was in that business for a while.
If you need to 920.453.2195
Doug
RE: Help with WR Motor Recurrent Failure
Further If you want it fixed right give me a call. Above post.
RE: Help with WR Motor Recurrent Failure
Also look at the shorting contacts of the rheostat, which could lose tension.
RE: Help with WR Motor Recurrent Failure