I recently picked up 8 units with this type of drive which I too think is the accord drive. One unit was shutting down and causing entrapments about once a week and the faults indicated a bad encoder resulting in uim. I replaced the encoder board on the governor but I don't think the board itself was the problem. When I replaced the board I noticed the 2 small optical horseshoe sensors on the old board were just barely around the disk on the governor. I adjusted the new board so it was up into the plastic notched disk by about another 1/8th of an inch. I haven't had another motion fault since. These units were also modernized around 2013 and the maintenance guy said they've been problem child's from day 1. I've had a few other issues that have all turned out to be poor adjustments to devices like the brake, rope gripper, and gate switches.
