text: <s>[INST] Powerflex 700 fault 121 I am experienceing this fault and did a search of the forum and found this, but it was left unresolved. http://forums.rockwellautomation.com/t5/forums/forumtopicpage/board-id/Drives/message-id/2212 . I was wanting to see if anyone has found a resolution to this fault. I have replaced all components in the VFD, then replaced the VFD. I am still getting the fault occasionally. Any ideas on what to check next? [/INST] We went into the VFD bucket, MCC and also the motor and tightened all of the ground connections. This seems to have fixed it. \\n </s>