Thread: How hot is too hot?

I flew my Trex 550 today with 553mm Edge blades, I'm using the stock motor which is the Align 600m. At the end of the flight I touched the motor and it was too hot to hold your finger on, I fly for 4 minutes on a throttle curve of 100-95-90-95-100. The heli seems okay on the power front but at the end of one flight i think i smelt electrical burning but not sure if it was the heli. The align 70A ESC was only at 40c at the end of the flight.

What are other peoples experiences? I have a IR temperature sensor I will take with me next time I fly but wondered if the motor is getting too hot and on the way out.

Thanks

Brett

With that set up I'd expect it to be pretty normal that the motor gets as hot as you say. On mine with the stock 520mm blades and 82% flat curve my motor comes down hot, but not that hot that you can't hold your finger on it.

Just a guess that all motors are slightly different and because of this the only way to get the motor to run cool is to be able to alter the timing and PWM values. These settings are available on the YGE ESC but costs alot more money. The same settings are on the HobbyKing yge rip-off and might be on the CC ESCs. These settings also affect the amount of power output by the motor so it could take a few flights to find the best setup for your motor.

You can do that on CC ESCs too. However the 600mx runs extremely hot (at least on my 600).

My 600MX ran hot using the Castle Recommended PWM on the ESC.

Change that back to Outrunner, and the temps halves.

Originally Posted by sacko

My 600MX ran hot using the Castle Recommended PWM on the ESC.

Change that back to Outrunner, and the temps halves.

What other changes are made when using outrunner? The drop is temp must be at sacrifice of something else?

This is always a difficult one to answer. Safe temps depend on the equipment spec. I don't know the safe operating temp on you kit but as an example my scorpion 520 le was landing with a temp of 170 on the coil and my hobbywing 120 esc was at 140 on the heat sink in ambient temps of 84. These a both just in spec ( I think 200 is max on the motor and 150 is tops on the esc. If you have a look on the manufactures specs it should tell you.