Hello everyone. First post and glad to be part of the group. I worked for otis most of my career and recently was hired by thyssenkrupp in December to take over route with mostly otis equipment. Im having an intermittent issue with a drive on a gcs mrl with a ovfr1a-404 drive. When I show up to the call the car is either in service with a drive fault logged or shut down in mcss on a drive fault. Always resets and runs immediately and runs for weeks. When I plug into the drive I'm seeing vac under fault and vac in balance. There's also a buss cap fail and pll unlock fault sometimes. Every once in a while I'll have an encoder feedback fault also but my encoder feedback seems perfect as I'm running the car and watching. So now that I've gotten that out of the way I am trying to tell the customer that I believe there is building power issues going on in the building. I plugged into the drive in the car at the other end of the building and the first three faults that popped up were all related to low vac. Any thoughts? I replaced the encoder because it was cheap and easy and we sent the drive out (even though I didn't want to) to be rebuilt. This customer is the federal government and are very difficult to deal with or I would have never sent the drive out.