Rolled up to a 20-story building in Austin and found the controller board fried

I got a call about an elevator stuck between floors, and when I opened the panel, there was this burnt smell and a crack right across the main relay. Had to bypass it with a spare I keep in my truck, got them moving again in 45 minutes. Has anyone else dealt with sudden controller failures in newer models?

3 comments

3 Comments

xenaf5112d ago

Actually it's worth mentioning that the "main relay" you're talking about probably isn't a relay at all in most newer elevators. A lot of those newer controller boards use solid state switching like MOSFETs or IGBTs, not mechanical relays anymore. I had a similar call on a 2019 model where the IGBT module shorted out and took the whole drive with it. So that cracking sound you heard might have been the potting compound splitting on a power module, not a relay body failing. Just something to keep in mind if you run into it again, checking the drive manual for the exact part numbers saves a lot of headache.

emery_black12d ago

Hold up, wait. Potting compound splitting? Ngl, I've never even thought about that being a possibility. I always just assumed that sound was a mechanical relay going bad, like the old ones with the cracked plastic body. Tbh, the idea of a power module just cracking open and taking the whole drive down is kind of wild. That would be a nightmare to diagnose if you weren't looking for it, so good looking out on that detail.

mila_campbell2511d ago

Yeah actually I think you're right about newer drives using solid state stuff. I had an Otis car a few years back where the IGBT pack blew and it sounded exactly like a relay failing but the crackling was way sharper.