All about Temperatures - what are the max. values?

To prevent overheating there’s max-temperature settings in the VESC Tool under Motor Configuration, Temperature tab. These settings specify when maximum currents will be reduced. The Float Package additionally gives you temperature tailback 3 degrees before the start temperature. Also the buzzer (if installed) will start beeping at that same temperature.

Motor Temps: 80-90C is usually safe, at those temps the magnets do get a bit weaker, and above that the glue holding the magnets gets soft so they could come loose. And above 100C is where you start risking demagnetizing the magnets, even with the higher end magnets used in our motors.

Most people have motor cutoff start at 80C and end at 90-95C

Remember: motor temps are vastly delayed. So if you see 90C while climbing you might hit close to 95-100C before it starts decreasing again.

Controller Temps: PCBs and electronic components can usually handle up to 100C just fine, but remember what kind of enclosure you’re using - if it’s a PLA/PETG print it’ll start getting soft at 70-80C, a bit higher for ABS.

Most people use mosfet cutoff start at 70C and end at 80C or 85C. With an all-metal enclosure you could probably safely up this to 80-90C, but tread cautiously. Here too, measurements are just on one spot on the PCB, so actual temps for individual MOSFETs could be higher.

Attention Floatwheel Users: because the controller sits right next to part of your battery, you don’t want lower controller temp limits than you’d need if it were about the PCB/components only. So you may not want to exceed 70C.

Battery Temps: Anything above 50C is bad for your batteries, above 60-70C may be close to thermal runaway and a precursor to a battery fire. If you’re using decent cells like Molicel p28a or p42a then your cells should never get hot during riding, even when pulling the occasional 40+ battery amps. It’s often the charging process that is the most precarious for Lithium Ion batteries.

Note: battery temperature related actions are only possible with a CAN enabled smart-BMS like the Xlite or the Trampa BMS. Also, there’s no battery related tiltbacks yet.

Notes on motor temps from rlyyy:
GT shuts down at 185f so thats where i set my thresholds.
Magnets demagnetize at high temps, Google says irreversible damage occurs above 200F and recommended staying below 180F or 82C
Up to 80C you should be on the safe side with some extra margin.

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Yeah even in my xr when I’d be doing nose drags non stop for an entire charge the battery wouldn’t climb above 150f only one time did it shut off from that and it was like the first week I had it… think couple times last summer I had to let it cool cuz I was pushing it to hard. Been really conservative w vesc barely letting a nose drag go longer than 50 feet cuz my dirty cycle was going up past 82 and float app sent alarm to go off which freaked me out