The Thermal fuse blew in my Ryobi DP102L drill press motor, while I was drum sanding. There were no markings on the fuse. The single phase induction motor is 1/4hp 3A (no load) 1750rpm on 115V AC, according to the manual. There's no name plate or information available from Ryobi. Comparing it to similar drill press motors online, it's probably Class A insulation, but that's a guess.
I want to replace the fuse with a thermostat type cutoff which will reset so I don't have to tear the motor down again. The temperature rating for Class A is 105degC. The device I'm considering is a ChemThermCanTherm T22, which comes in a variety of trip points which match the different NEMA classes.
Research online yielded only two results for this specific question. One suggested 25% above the rated temperature. Another, which was an article about thermistors, suggested 10%. The trick of course is to have the thermostat remain closed under normal operating conditions, but trip if I push things too hard (like drum sanding at too slow a speed) then reset when things cool off.
If I understand correctly, I don't want the thermostat to trip right at the rated temperature like this one : T22A10505DFFBG0E. But slightly above like this one: T22A12005DFFBG0E. See full list here: ChemThermCanTherm T22
Does the device I'm choosing makes sense? Are there other considerations? Are there any issues with the current capability of the T22 which is much higher than the required 3A of the motor?
Thanks.