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Have I been a donut????.....probably

Brian fred carr

Site Moderator
In my inexperience I have just put a 40c 11.1v 3cell lipo on my slinger
that has a 30 amp esc it ran lovely for a half a minute then started smoking (the esc)
and got really hot......so does the 40c part mean I have overloaded the 30 amps....
look forward to someone putting me right...thanks in advance


Stuck in Sunny FL
Staff member
the "C" rating only tells you how fast you can drain your battery safely.

You need a watt (amp) meter to be able to test your set up.

What motor and prop combo did you use?


Old age member
You can not blame a to big battery regarding C or mAh to destroy an esc. (You don't tell the mAh of your battery).
You can put to many cells and get to high voltage but that is rare.

It is the motor and propeller (and the voltage) that decides how much is pulled from the battery.
If the motor-esc-propeller combination has been working before something must have gone wrong.

A to big prop makes the motor draw more current that can destroy the esc.
If the esc is shortened then the battery can get hot and possible get ruined if you are not fast to shut down.

A failed ball bearing in the motor can cause the same.

Most likely is that you got something wrong in the esc - failed soldering caused by vibration, "hard landing", moist or bad manufacturing.

Brian fred carr

Site Moderator
Thanks for the quick replies fellas I have put a bigger prop on it so there is my problem
I reckon and it did spend three (count them THREE) days in a tree so it did get damp.
It got so hot the solder melted and all the wires fell out.....LOL...It was a 2200kv motor
with a 7x5 prop............once again thanks
Last edited:

Tom O'Connell

Bixler FPV Mods Fantastic
this shouldnt have affected the esc though, maybe the motor should have been the one smoking. However, you did put a 7x5 on it and im guessing (not knowing the motor) that it should be taking a 6x4 size. That 7x5 would have been making the motor pull too many amps for that esc to handle, hence it burning :)
hope that helps