That controller board swap that took me 6 hours (should have been 20 minutes)

I was working on a Gen2 MRL in a building near downtown Austin last month. The drive was faulting out every few cycles, so I swapped the controller board like normal but the same fault came back. Turns out I spent 5 hours chasing a bad encoder signal from the motor, not the board itself. I should have checked the encoder wiring first instead of assuming the board was the problem. Has anyone else had an encoder wire rub through and cause intermittent faults like that?

2 comments

2 Comments

jessicamiller1mo ago

Blame the board first every time if you want to waste half a day. I've seen way more encoder wires chafe on the motor junction box cover than bad boards on Gen2s. That MRL probably has the little plastic wire tie rubbing against the metal frame, you find that and you're done in 20 minutes.

anthony_fox901mo ago

Could be the gate switch bracket cracked from the counterweight hitting it during a hard leveling stop. Had that cause an intermittent fault once that mimicked a bad encoder perfectly.