We were able to successfully start the air compressor motor after removing a plug in the coupling to relieve grease and allow for axial movement. We also moved the shaft out to magnetic center prior to the start attempt. It seems the culprit was us being hydraulically locked from the grease in...
I haven't examined the relay files yet to fully understand what the "locked rotor fault" is exactly showing, but it is obvious that the current never drops down after startup. We have another compressor that is redundant to this one that jumps to 800 amps on startup and is below FLA (215) within...
Rotation is correct.
The motor does turn and seems to be accelerating. We have checked for open phase. Everything at the breaker (autotransformer, contactors, etc.) all tested good. Unloader valve has shown open.
This motor is run off of an autotransformer (korndorfer) starter. The fault is coming from our motor protection relay which has all previous settings that it had when the compressor ran fine before the motor repair. The compressor is free to turn by hand so doesn't seem seized. The start current...
We have a Siemens 1750 HP 3600 RMP 4000V motor that is used on an air compressor. We recently had the windings replaced. All motor shop test results looked fine. We got the motor back, done an uncoupled run to identify magnetic center, aligned and coupled the motor. We get a "locked rotor fault"...
