View Full Version : MGM Compro 8012 / Feigao 8s Problem HELP!
I just received a used MGM Compro 8012 & Feigao 8s and I am having problems getting it going. I programmed the controller via the manual, with the leds responding accordingly the entire time.
The minute I connect the motor and try to run it, I get a quick rotation out of the motor and then it goes dead. Same thing happens in forward & reverse, whether it is connected to the truck or spinning freely. I know it is not binding at all as I can spin it freely at any given time. The motor leads seem to be connected to the controller correctly.
The manual stated that the motor would beep throughout programming, so I connected the motor and reprogrammed. Throughout the entire thing the leds once again responded, but I did not see any life from the motor.
Seeing that this is my first brushless system, I am completely lost. HELP!
SpEEdyBL
08-31-2006, 12:31 PM
First make sure that all connections are tight. Yank on each wire to test this.
It sounds like you programmed it correctly. Were you able to set each of the parameters? If not, it is important that you set the low voltage behavior to "Slow reduce rpm" mode, because the motor will just cut out if the battery voltage drops to 5.5 volts. (You'd be surprised how easy it is even with a fully charged pack).
What batteries are you using and what car/gearing are you running? Also, be sure that you are using high quality connectors on your battery and motor (unless they're directly soldered).
I am not at home right now to try some of the things you have said, but I definitely will be trying those tonight.
I originally tried using the default Car mode, and then tried to set the parameters. But seeing as I don't know what parameters levels I want without running it, I ended up picking nearly the default again. I think the default low battery setting is to reduce, whereas "cut off" is one of the other options.
I am using fully charged GP3300's in 7-cell & 8-cell (2x4-cell) combinations. I also had a semi-charged 3000 pack which I tried with the same result. The batteries / controller are using Deans, and the controller / motor are using 3.5 mm motor leads which were installed by the previous owner. The connections seems snug, and I can't see any fault in the wiring.
I will try to reprogram all of the parameters tonight and see.
If it makes sense at all, late last night I was able to get it running in a constant fashion if I held both ends the motor very tightly and on its side. I was able to reproduce this affect on more than one occasion, although this morning I was unable to when I tried.
Other than one initial try, I haven't actually put it in the vehicle again because it was extremely violent on the gears as it did its quick rotation. The motor itself almost shakes violently, rather than just spinning the shaft. The vehicle is a HPI MT2 converted electric, which was also bought by the same person I got the brushless setup from. He had been running this setup previously without problem, so I now the setup should work together.
I emailed him and so far he said to try another radio / receiver. I don't have one, but I am going to grab a friends and try. I just can't see it being the problem though? I have a MX-3 with an Airtronics receiver.
I will keep you guys posted, and if you have more ideas please let me know. Would video of what is happening help (I can probably get that easily).
SpEEdyBL
08-31-2006, 01:19 PM
If your motor is shaking without a pinion gear, then your motor is definately the problem. There should be almost no vibrations from the motor when its running.
Rtsbasic
08-31-2006, 03:46 PM
The MX-3 is a good radio and shouldn't be the source of the problem.
How far did the motor screws you was using in the car thread into the motor? Its very easy to touch and potentially damage a winding by using screws that are too long. It sounds like the motor is damaged or not wired in correctly. As you have had the ESC successfully startup the motor a couple of times I would guess its not the radio, or the esc at fault.
Before I ever connect to motor to a machine, I always do a test run without any resistance. With that being said, I am running it without any screws in it at all, so nothing is binding.
I can freely turn the shaft by hand with ease. There is no clicking, binding, resistance of any sort ... everything seems smooth. The only time it shakes is when I put power to it.
I am going to try and video it tonight and post it up so that I can actually show you what is going on.
Rtsbasic
08-31-2006, 05:22 PM
That didn't answer my question mate. Its been fitted to the car so its possible that in doing so it become damaged. Feigao are cheap and cheerful motors, and aren't the best built in the world. A screw going in too far into one of the holes can scratch off the windings insulation, and cause it to short, which will make it a bit jumpy. Its not a case of the screw causing something to bind. Also if you bend the wires around the front of it too much you can also damage them. You wouldn't feel anything odd when turning the shaft as there is no physical connection between the rotor/shaft and the windings/case.
Sorry, I obviously misunderstood. Seeing that I don't know much about the history of it other than what was told to me, I have no idea what was done before and everything came pre-wired. I obviously can't eliminate the fact that I have done something to cause this, but I would say it is minimal due to me barely touching the damn thing.
Here is a video of the problem, as well as you can see how when I hold & squeeze it works fine: http://www.cmcarthur.com/brushless_problem.mpg
I am going to try additional programming and other things to try and figure out this problem. Let me know if the video helps identify the problem.
badboy2
09-01-2006, 02:46 AM
off topic ur video is so clear which camera is that?
Canon PowerShot S1 IS.
I even compressed the video a lot, so the source video is MUCH better. I love this camera.
Well, good news about my problem though. I removed all of the shrink tubing on the motor leads and long and behold 2 out of the 3 connections were SERIOUSLY loose. I broke them apart altogether, and put in a temporary solder fixed, through on the controller, and viola ... fixed. I will have to do a proper job this weekend and test for sure, but I think my problem is solved ... thank god.
Rtsbasic
09-01-2006, 09:37 AM
Didn't think of that, just assumed it was directly soldered. Now you've repaired that it should work fine, I had a similar problem before which caused the same result.
badboy2
09-01-2006, 01:53 PM
is this the one ?can u make vids from that?LINK (http://cgi.ebay.com/CANON-POWERSHOT-S1-IS-3-2-MP-DIGITAL-CAMERA_W0QQitemZ330023328488QQihZ014QQcategoryZ463 15QQrdZ1QQcmdZViewItem)