how hot is too hot - RC-Monster Forums

makana59 · **how hot is too hot -** 03.12.2006, 11:50 AM

Aloha Guys,
What I understand about the BL motors is that a tempurature that I should not excede is about 160 degrees for the motor but what is a good temp to keep it under for the controller? I have a 9920 and was wondering what too hot is and what temp should it be running about. I have a Feigo 9L and 9920, running 14 cells IBs. I dont know what else would realy matter for the heat. Thanks guys. Makana

Sneeck · 03.12.2006, 11:54 AM

The motor shouldn't get above 110 degrees. Controller is somewhere around 90 degrees I believe, not sure though. Stick a fan on it to be sure it stay's cool.

squeeforever · 12:14 PM

the motor shouldnt exceed 160 if at all possible but make sure the controller doesnt go over about 140. heres the link to the sticky in the facts and questions forum

maxxdude1234 · 03.12.2006, 01:46 PM

Anything under 180F is safe with a motor. Anything over this and the neodymium magnets start loosing their permamagnetism. Like squee and sneeck said, aim to keep temps under 160F and you'll have no problems.

makana59 · 03.12.2006, 04:20 PM

thanks for the help guys... now I just need to get a heat gun thing

GriffinRU · **Motors and ESC Temperatures... -** 03.12.2006, 05:00 PM

Keep motors and ESC at 70-80C
Personaly if I can keep my hand on motor or ESC for 3-5 seconds then temp is OK, Less is bad more is great (but maybe overkill :))

ESC can handle up to 160C (Based on FET's specs, but not true for microCPU and components inside...) but above 70C efficiency goes south.
Magnet inside motor can handle up to 350C but checking magnet temp is very difficult. And with temp rising heat transfer from magnet to can becomes less efficient. While windings resistance goes up with temp, pulling motor efficiency down.

Artur

brijar · 03.15.2006, 10:59 PM

I still don't feel safe with my motor being too hot to touch. I measured the temps with my infared temp gauge and they were usually about 60C average, 50C low, 70C Max (140F average, 122F low, 158 High). I see everone with these heating issues with their ESC's, but mine just barely gets warm, just a tiny bit warmer than room temp. I'm used to brushed motors with the rule: If you can't hold your finger on the motor for five seconds, it is too hot and probably overgeared or binding. I can barely touch my 9L after a run, let alone hold my finger on it. I am running: 9L/9920; 16/72; Stock parts: Maxx sized wheels/tires; diffs; tranny. I've made sure it is free of binding and rolls smoothly, but it still heats up like that. I've got it in peices doing my "Spring Cleaning" after a recent high speed encounter with a tree. I'm going to be making an order and would like to know if I should get an 18t pinion to try, or just stay with this, maybe switch to my 66t spur. In the stickied thread, it said:Hot motor, cool esc = under geared, so I might want to try a new pinion. Man I'm long winded.

Thanx,
Brijar!!!

Sneeck · 03.16.2006, 12:39 AM

Sound's like it's undergeared. Try 1 tooth on the pinion and see how hat goes. Still hot, try another tooth on the pinion.

coolhandcountry · 03.16.2006, 07:42 AM

You Could try a larger pinion or the smaller spur and see if the temp goes up or down. I always seem to have a problem with the L cans getting warm on me.

maxxdude1234 · 03.16.2006, 12:20 PM

brijar, the finger thing is a waste of time. Aluminium always feels ALOT hotter than it really is - its to do with heat conduction/convection. Try touching a black car on a hot day and then try touching clear glass, they feel completely different, but their actual temps will be pretty much identical. Tempgun is the only way.

ps. most brushless motors have aluminium cans, as opposed to steel brushed cans - aluminium conducts heat better than steel.