text: <s>[INST] 4160 VFD Summary: Synchronous Transfer ProblemsWe have a 4160 synchronous transfer bypass system for two motors that will not synchronize with the fixed frequency buss to allow the transfer. ANy thaught on where to start looking? Could it be the isolation transformer? [/INST] Wow !! I guess this is with Powerflex7000 drives, best to leave it to the experts and get a Rockwell field support engineer involved \\n </s>