dinuka

Is it normal for a 30A ESC to Get warm and a brushless motor to get hot After about a minute os continues spnning?

elmote

Yes
Add a heat sink if you like

Elmo Te

thecheatscalc

what motor? for the align 420LF a heat sink is actually detramental as for the way it's built after a full 2200mAh battery it's colder than the ESC and thats just warm. now for the others if it's under load yes they should get "hot" but not so that you can't hold it for at least 10 seconds. if your ESC is warm that's good. if the motor is too hot to touch, your heli has some binding, or somethings too tight.

RK-Aircraft

My Feedback: (81)

If you run it stationary, it will get even hotter. Get a heat sink. If its for a plane, make sure there is plenty of airflow over it, the esc and the batteries.

thecheatscalc

heh when flying mine stays cool, it's always below 120 degrees.

credence

My Feedback: (2)

This varies very much among motors.

On smaller brushless motors, they usually stay pretty cool, the larger you go though, the hotter they seem to run. Most motors can take the heat without much problem. However, if it's getting to the point where it burns instantly to the touch after only a minute of use, it's too hot. Check your gear meshing and make sure you have no binding anywhere. Also make sure you're not trying to push your motor. Some motors just aren't strong enough for some uses, and if you try to use a motor in something it wasn't intended to do, it's going to get hot.

Also, some motors just run hot, and having adequate cooling for them helps. If you don't have one yet, get a heatsink. ANYTHING that pulls heat away from the motor rather than leaving it there will help. The only reason not to use a heatsink is if the motor (for some reason) has ventilation holes on the sides rather than the tops or bottoms. A heatsink would cover these up and probably make things worse.

dinuka

Actually the motor is not instaled I just hookesd the wires and the ESC to Rx just to check weather it works I still didn't get the motor gear yet and yes it is a pretty small Tower Pro Motorabout 2inches long

thecheatscalc

why I'd say the heat sink is detramental is because the wall of the 420LF has air blowing on it from both sides, but mainly from the inside. If I added more metal such as a heat sink this would allow the sides to retain more heat as right now it retains none. this would make the air flowing through the motor pick up more heat and would probably make the motor run cooler, that's the theory anyways. now most motors DON'T have a way of cooling so in that case, a heat sink will help. If you have an outrunner try punching holes in the top and angling some of that metal so it scoops the air into the motor.

Tiger27

The walkera brushless is sealed so a heat sink made from a aluminium can folded concertina style and rapped around works very well to keep the heat down.

credence

My Feedback: (2)

Heatsinks, if properly applied, don't trap heat, they move it.
A heatsink around your 420LF would take the heat from the can of the motor and absorb it. You would then use that airflow to cool the heatsink instead of the motor. All heatsinks work on this principle, including the ones in your computer. They move the heat away from the source and then use ambient moving air to cool the heatsink so that it doesn't become over-saturated with heat, and thus can continue to absorb more heat, in an endless cycle, keeping the motor cool.

If your heatsink is properly applied, the motor will be only warm to the touch, while the heatsink will be hot. This is how you know the heatsink is doing it's job .

thecheatscalc

the problem is the outside of the can is really just a bit above room temp. I'm not sure how a heat sink would help in that situation, well we can do a test. Hey traveler, you got the heatsink, do you think you could try running the heli with and without the heatsink. I'd like to see which is cooler. this should be interesting...

credence

My Feedback: (2)

If you're running cool than a heatsink will not make much of a difference as theres no heat to transfer. My point was, if you're running hot, heatsinks almost always help, rather than cause problems.

sparkling_fist

my esc gets warm but it seems ok.
i put a heatsink on my motor its ok as well

Traveler

Hey thecheatscalc,

I just installed an FMA Co-Pilot and tie-wrapped everything neatly in place. Taking out the heat-sink now would mean dismantling the whole thing again, not to mention that the royally applied cooling-paste would leave a mess. I don't think I'll remove it until I need to. :-)

With the heat-sink on, the 420LF runs very cool. After minutes of hovering, the heat-sink is just warm to the touch. One intresting thing I noticed, is that the temperature on the heat-sink actually seems to increase for a short time after landing, probably because the ventilation is gone and the remaining heat leaks into the heat-sink. It just needs a minute or so after landing to have already cooled down significantly again. As mentioned earlier in this thread, my (Align BL-25G) ESC tends to run a bit hotter than the motor in flight, but not to the point where I can't keep a finger on it. Ambient temperature during most of my tests was 24-26 degrees C, indoors. Outside, where it's about 10 degrees C cooler at the moment, things don't seem to heat up much at all.



Grtz,

Traveller

thecheatscalc

well that's how mine runs as well, except there really isn't that much heat that comes out after I turn the power off. oh well, I don't want you to remove the heat sink if it's that much trouble. but I think they've gotten the cooling system just right so it really doen't need the heat sink, but if you really want it get it, can't say the same for other brushless motors, you'll always need a heat sink for them, but why is it that under no load they run hotter than under load? (at least mine does)

dinuka

Thanks a lot guys i'm new to brushless so not really famalier this these issues well might as well get another heatshin just to be on the safe side