2 ms·
Overheating shutoff of the 'dumb' kind is usually a bimetallic strip, though maybe this works as well
by raverbashing 3y ago
Overheating shutoff of the 'dumb' kind is usually a bimetallic strip, though maybe this works as well
- jacquesm 3y agoNo, you got it right. It's a bi-metal in all electric motors that I'm aware of that have overheating protection. I actually had a dangerous situation here once in a big compressor motor that had a faulty soft-start circuit, that caused the bi-metal contacts to fuse so the protection no longer worked. By the time I noticed the compressor motor was way too hot to touch.
- TeMPOraL 3y agoDoes bimetallic strip have some kind of passive hysteresis? Because what I observed with my shredder is that, if the overheat protection kicks in, it won't turn on for the next 20-30 minutes. You can flip the switch, or even unplug it from mains, doesn't make a difference - it won't turn on for almost half an hour. Now, that could be explained by e.g. the engine itself having enough thermal capacity to keep the shutoff switch active for a while, except... if you are careful and do small pauses between shreddings, you can keep going indefinitely - and those pauses don't feel enough to let the engine cool if that was the only thing that mattered. Like, you shred something for 3 minutes straight and get 30 minutes cutoff, vs. shredding something for 1 minute, then 30 seconds break, then 1 minute, then 30 seconds break, ... and you can keep going like that for hours.
- raverbashing 3y ago> Does bimetallic strip have some kind of passive hysteresis? Yes, and it excels at it. From your description it does look like it