EDF Motor Cutting Out - RC Groups
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Dec 10, 2012, 10:25 PM
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dedStik's Avatar

EDF Motor Cutting Out

Need some help with this one and I've literally tried most everything.

I've got this motor. It's a 4300kv that runs on 3S pulling about 30 amps. I'm using a Parkzone 30 amp Pro esc for it, which should be fine. Using Watts Up meter and full 3S lipo I'm pulling 32-34 peak amps at WOT and voltage shows steady draw.

After half throttle most times, the motor shuts down. Watts Up meter showing 10 amp and steady voltage when motor shuts off. There are no sounds from the esc prior to shut down, throttle must be returned to zero before motor will restart.

I've tried resetting the timing on the esc down from 5 degrees (the motor has 6 poles near as I can tell without disassembly) on up to 25 degrees. Ran thorough tests using Watts Up meter each setting and showed no variance between timings, all test results were similar to what was posted up top. Each test the motor shut off more often than not at half throttle.

I've tried rebinding the rx, I've also tried deleting the model from tx and reinstalling it, as well as double checked throttle trim and resetting throttle range. The esc does arm properly.

Inside fan shroud shows zero signs of fan contact with wall.

I have tried 3 different brand of lipo and each reproduce the issue. 1 lipo was borrowed at my local flying spot yesterday from a fellow flier that attempted to help me resolve the issue.

Have not tried another esc as I'm unable to reach the fan unit in the plane. The plane build is the Fuglyjet. I'm willing to rip it up to resolve this issue.

Any tips or offerings on how to proceed would be appreciated.
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Dec 10, 2012, 10:45 PM
Registered User
How hot is the ESC getting ? Where does the air come in ? Is there a big enough exhaust opening ?
Inlet should be 2X larger area than the exhaust area.
I recall people saying that a ESC has the greates strain at 1/2 throttle.
Dec 10, 2012, 10:52 PM
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dedStik's Avatar
3" opening in nose for airflow, fan unit is only 64mm (3 in). ESC can be touched indefinitely meaning there isn't enough heat to make you remove your skin from it. Not really even warm to the touch, neither is motor after running for a few seconds at WOT.

That last sentence seems about right, if I can get it past 1/2 it seems fine from 60% up to 100% throttling up and down, sometimes though it hits that half mark and off it goes, even if it's 100% and dropped to 50 or below it shuts off.

If I have to I'll buy another esc before flying it.
Dec 10, 2012, 10:54 PM
Registered User
I vote a bad ESC. Can you get a FREE replacement ?
Dec 10, 2012, 11:05 PM
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dedStik's Avatar
Sadly no, I made the plane from stuff I had on hand, cept for the fan and motor.

I'm not worried about spending some money to get another esc, I could always find a use for another esc.
Dec 11, 2012, 09:37 AM
Registered User
parpar1's Avatar
What is your ECS (BEC) shut down voltage set to? SEt it to the lowest voltage you can. If i set my to 6 i get the shut down. If i keep it a 5v not so much.

Throw a volt meter on your balance plug and hit the gas and see how low your voltage goes to after a bit.

Worth a shot
Dec 11, 2012, 10:31 AM
Registered User
I had a problem very similar to this a few weeks back. Two questions, on your esc, did you have to extend wires at all? and if so which side did you extend, the motor side, or battery lead side. If you extended the battery side, that is likely your problem. Also, for the whole setup, what gauge wires are you using? I also had a problem, where the wires were too small, and my wires were basically burning and turning black, and melting the insulation.
Dec 11, 2012, 10:38 AM
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dedStik's Avatar
@parpar1 not sure the shut down voltage, will check tonight when I get home, I can also post video tonight of the issue.

@stingeragents, yes I did have to extend wires. I extended the servo side as extending the battery side as far as I can tell is a bad idea. I used a 6 inch extension. The gauge wire is whatever was on the esc and motor as well as battery. I added nothing to them. Only used a servo lead extension to get the esc to reach the rx.

Tonight I'm cutting an access port to ensure my connections are good between esc and motor.
Dec 11, 2012, 10:40 AM
Registered User
That might be your problem. I have never gotten an esc to work right when adding an extension to the servo lead. I have no idea why, maybe its just me, but it never worked for me. I actually usually can't even get the esc to work at all when using an extension. I'd try that. Also, while you got it open, make sure the motor bullets arent touching each other unless they are fully heat shrinked. That can cause problems too.

I just did some looking for you, as I've never looked up the issue myself. In THEORY, there shouldn't be an issue using a servo extension from the ESC to rx, but I did see that some people had throttle issues while doing it. Some fixed the issue by using a different extension, some say to put a "choke" on the lead to get rid of interference ( I believe a choke is a ferrite ring but don't quote me). So if at all possible, i'd try to remove that extension, and run just the original wire to the rx and test it. You may have to take the rx out to get it to reach, but at least then you will know if the extension is the problem or not. If it works fine without the extension you know 1 of 2 things. Either the extension is bad somehow, or you need to add one of those rings to get rid of interference. If you have another extension laying around, you could try that and see if the problem still exists. Like I was saying though, I personally have never gotten it to work regardless of the extension. Might just be the esc's I'm buying or something, IDK. Either way, if without the extension it works, your easiest solution will be to just relocate the rx. I don't know that plane you have, but you will be better off adding extensions to the servos then adding the extension to the rx.
Last edited by stingeragents; Dec 11, 2012 at 10:52 AM.
Dec 11, 2012, 11:04 AM
Registered User
I bench test every new ESC with 3 foot long ammeter leads in the battery connections side & voltmeter leads. Never a problem. I use only B P Hobby & Feigao ESCs. From 6 A to 40 A 2 to 4 cells.
Dec 11, 2012, 11:38 AM
Registered User
Hmmm. Idk. Maybe im just unlucky. Either way its something for him to try
Dec 11, 2012, 11:56 AM
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dedStik's Avatar
At this point I'd rather exhaust every option to diagnose it. I'd feel much better finding out it was something that simple than to try to fly it as is.

You had also mentioned extending the leads from the esc to the battery, I was under the impression extending them either side was not a good idea. If that's not the case and it is fine to extend the esc side I can safely eliminate that extension to get the esc to the rx, the only reason I added it was to be able to have the esc reach the battery.
Dec 11, 2012, 12:06 PM
Registered User
priorty wise.

Short battery leads
short motorleads
short receiver plug leads
Keep the antenna away from everything if possible.
anything pretty much goes after those steps.

Keep the high current ESC leads away fro the skinny plugs / leads.
If you MUST have small leads cross over high current ones ?
have the little guys cross over at a 90 degree angle. Cuts way down on interference.
Dec 11, 2012, 01:20 PM
Registered User
Extending the motor side is not a problem
Dec 11, 2012, 01:27 PM
Registered User

But in terms of radiating interference to the rest of the system. It is a good idea as range is extended.

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