I have 18 schindler 330a hydro at one facility (5 buildings)
About once a week random units are getting motor wiring faults on the siemens 72g soft start. Sometimes 1 unit will be down sometimes as many as 5.
Never have any faults in the controller just the motor wiring on soft start. Press up and down on soft start to reset and the unit will run fine.
I've checked everything per the siemens manual and have talked to siemens tech support.
Motor wiring checks ok
Fault contactor ok
SCR check ok
We believe it is a building power issue. The customer is reluctant to believe this.
I just wanted to throw it out here to see if anyone has had something similar.
Thank you