Brushless motor problem

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josh
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Post by josh »

I'm not sure how the pulses work towards the motor but can you not take the motor off and put an LED across two of the motor terminals from the esc and it should flash if there is a power output to the motor from the esc in which case showing a problem with the motor not the controller?
(LEDs are pole sensitive so if it doesn't work at first try fixing it the other way)
Have you tried putting it on a different channel?
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Remote-Controlled Dave
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Post by Remote-Controlled Dave »

I agree with Josh. If you haven't heard the beeps its more likely to be the controller than the motor.
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Post by Team Orr »

hey

i just put a green LED across the + and - terminals and sure enough its flashing :-) so that must mean its a problem with the motor?

and yeah i have tried different channels, no difference
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Post by Team Orr »

Yeah...basicly just tried everything and nothings working...hmmm :/
Still a while to go before the AWS so im hoping we figure it out soon...
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muchalucha
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Post by muchalucha »

The robotbirds 10 amp esc is exactly the same one as the hobbywing 10 amp esc. The giant cod website has a bit more information on the esc which should give you a bit more of an idea whats going on. It may be worth checking that the motor isnt reving too high for that esc. its a 2000 kv motor so 2000 times 8.5 is 16800. The website states a max of 35000 rpm so this shouldnt be a problem.

And as others have said, some motors just dont like some escs. If you can get hold of a different motor that the esc does like, this should allow you to hear the beeps and program it for different timings, which might bring your motor to life. Having said that I cant imagine why the beeps wouldnt work if the timing was wrong.

And as said above, the wires on those motors are just 3 leads from the windings twisted togethor and soldered at the end. If they have been wiggled it is possible one has been snapped. You could try cutting the heatshrink covering alkong the length with a knife, sliding it off and checking all of the wires to make sure none have fractured.

To verify the motor is working correctly, try this. Get 2 leds and solder the legs togethor in opposite polarites, so + to - and vice versa. Then tempoerarly solder this to each of the 3 legs ( do this 3 times trying 2 legs every time). Each time, when the motor is rotated both leds should flicker.

You can also test the esc like this, just attach a 200 ohm resistor to one said of the led pair and repeat the test like you did with the motor. If on the escs or motor either of the leds dont flash then there is something wrong. If the motor is at fault then try looking for cracks in the wiring. Short of that, it would need a total rewinding which is no easy task to get right. If its the esc, there is even less you can do. Its probably a blown fet if only one led isnt working on one test. But even that would require some really tricky smd soldering that probably isnt worth it for a cheap esc.

One last thing to try is a 3 cell lipo, A few escs have come out of china labelled as 2-5 cells (for example) but actually dont work below 9 volts (3 cells). So if your setup comes to life on 3 cells then that may be the problem.

If none of that works then I really dont know. If you can get someone to lend you some other brushless stuff it should be possible to find which component is at fault fairly easily.

Its obvious, but easily overlooked. But how big is your lipo and whats the C rating. If your trying to pull 6-7 amps from a lipo that is 300 mah and 15C then you are going to run into problems. The esc may refuse to start, or it could work, and your lipo wont last very long.
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muchalucha
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Post by muchalucha »

Fight or flight ... ?

...suicide
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Post by Team Orr »

i tried the LED thing tom, the ones on the motor didnt seem to flicker at all and the ones on the ESC flashed nice and bright so im guessing its the motor

im thinking of cutting the heatshrink off to see if i can see any breakages, if i find one would it be possible to resolder? failing that il just buy a new one and be done with it...hopefully that will work :-P il bring it along to the AWS

oh and its defo not the ESC rejecting the motor or anything, as its the same setup Dave uses in divinity (i think? has had upgrades)

Thanks
Jack
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razerdave
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Post by razerdave »

What I found with those motors is that solder didn;t stick very well, because the wires were enammeled, thats why it came with connectors already, but a little scraping with a stanley knife and I was able to get electrical connection.
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Post by peterwaller »

If the motor is not bleeping and you have shortened the wires coming out of the motor then I believe as I said before it is the connections to the motor.
You need to unsolder the connections and make sure the enamel is carefully scraped from each wire before twisting them back together and resoldering them.
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Post by josh »

I just ordered a motor from hobbyking and ended up getting another from robot birds that I'm actually using so if your after a new motor send me an email or a pm jack and I'll find the specs for it.
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