So I cracked my motors open the other day to replace broken halls. I saw the rear BPM was a bit roasty so decided to install a 105C temp cutoff switch inline with hall supply. I did the same on the front GM mini and epoxied the switch to the windings to have a direct contact for quicker operation. Went for a run yesterday but soon it turned out the 105C switch blew too easily.. it took a short (1km) ascent on the GM mini only (rear not connected yet) at 20mph. long story short I got home no problem, but it took the switch too long to close again so I had to pedal for quite a while on my own.
For me it's surprising I can reach 105 degrees on a regular flattish commute so fast. The motor case was barely hand warm at that point. Now I understand why the BPM windings were so toasty.. I must have got it to 150deg regularly since the case got quite hot at times riding at 30-40mph.
So I'm back shopping for some higher temp swithes. Which temp should they take without damage? 130 or 150 degrees?
For me it's surprising I can reach 105 degrees on a regular flattish commute so fast. The motor case was barely hand warm at that point. Now I understand why the BPM windings were so toasty.. I must have got it to 150deg regularly since the case got quite hot at times riding at 30-40mph.
So I'm back shopping for some higher temp swithes. Which temp should they take without damage? 130 or 150 degrees?