I have a gearless ultron DDC with an Allen Bradley drive that keeps throwing HF, F8, F2, F1. Sometimes unit will run fine for a few hours and sometimes it will run about a foot before shutting. While attempting to troubleshoot while it's doing this the thing starts running fine again.

motor field connection problems, vp 13 or vp32 both motor field problems. maybe a bad motor field connection, or bad field feedback board.

do you have a service tool or diagnostic software?

Bad feedback board