Diagnose this one!

DucktileMedia

Drone Enthusiast
Ok, so apparently I was not as meticulous as I thought I was being as I left one of the negative wires off of an ESC! I had no idea until I had another bad esc which I decided to recently replace. what baffles me is that the ESC seems to have been working. I am using the HoverFly pro board which gets its power directly from the same power distribution as the ESC's. I have an X8 and apparently 2 ESC's have not been working normally this whole time. They spun but were not offered full power. I had NO idea as the heli flew perfectly every time. but what I am more interested to know is how the ESC that had no negative going to it was able to perform normally. I can only conclude that it made ground through the Hoverfly board which means all that juice is running through a 16ga wire, to the rx leads?? If this is true, then this is proof that the hoverfly is built very well and that an octo does fly well on 6 or 7 motors. The other bad esc probably did work ok it just had issues starting.

At the same time, I think this may be a problem to consider. If the ESC is able to make a circuit using the hoverfly board, then this is not really a good thing. I know it is a rare and stupid oversight but it happens. My excuse was that I had 48 wires all going through the center of my 2 plates and it was an eye sore just trying to get all of them hooked up. As it took a month to wire up and 3 days to replace it, i realize that neat and tidy is not always the best thing for being repairable on location. if this had happened on site I would be screwed.
 


DucktileMedia

Drone Enthusiast
They have BEC's. Turnigy plush. Ok, so here's something else that's very weird. One motor stutters, which is why i swapped esc's in the first place. but now the same motor still stutters. I concluded it was the esc after trying the same motor on 2 other esc's and it worked fine! So now that I have a brand new esc it is stuttering, this time worse, barely moves. I try another esc on it and it works fine and the esc that was going to the stuttering motor works fine with a different motor? Is there some kind of pairing phenomenon going on here? Never experienced this at all. The esc's have been throttle calibrated individually, then I did them all at once. The programming card settings are identical and correct for all 8 esc's. WTF is going here???

I think the heli knows it has an upcoming job and is being juvenile.
 

kloner

Aerial DP
kids, i tell ya

so yea, the ground is linked through the pwm wire. These things run relatively low current per motor.......... it sure is possible what you think happened happened

stuttering is usually a wire not making connection on the motor side, can be loose at teh motor, loose at the bullet or loose at the esc. if you push the bullet in and out if there are any help anything?

were sure there isn't a timing thing you didn't change on the esc?
 

kloner

Aerial DP
http://www.hobbyking.com/hobbyking/store/uploads/708075066X189350X31.pdf

that startup setting is important too.

I've also just had esc's drop one of the amps driving one of the motor wires and do this mid flight. Would start, fly bitchen, 2 minutes in fall like a rock, next flight 20 seconds, then 2 flights were fine. WEird cheap esc's... mine were rctimer, but same thing. It used to every now and then get locked in a stutter and not start

if the hobbywing esc programer works with this, i'll let ya borrow one to get it going. there a pain without it to know everything is set right
 
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DucktileMedia

Drone Enthusiast
the esc works fine on another motor. I have the program card, they are all fine. I have Hoverfly's recommended settings and they have worked before. I permanently switched the 2 esc/motors that seemed to work better with one another. it just doesnt exude confidence not knowing whats different about the 2. I have a feeling this is why people buy AXI/Kontronic!
 

DennyR

Active Member
The ground/neg. has returned through the black wire on your PWM cable. This has probably caused some damage.....
 


3dheliguy

Member
Yeah, I have learned this very well in testing performance, If you buy cheap u get cheap, Kontronics top notch, AXI top notch... If you look at the most professional rigs you will see this setup, or Herkules... I'm personally going to try the Maytechs, kopterworxs and almost all the Big retailers support these ESCs, that's always a good sign. Also I have seen them run in person... They get a little warm when running the Big AXI 2826 and so does the motor, but no failures that I have seen.

Also I have heard something about incompatibility with these ESCs and the HoverFly, I will be running Wookong, and these are recommended for this setup. Also Tiger motors are supposed to be good, I will be trying the KW8 as I have an interest in them for more lift, and a cheaper price, sometimes cheaper isn't always better, and don't get me started on Castle Cremations! Def dont use those.
 

3dheliguy

Member
Sorry to hear about your prob tho, I would def ground my rig till I figured it out, as I couldn't afford to have an accident with full payload.
 

DennyR

Active Member
You have a brain...So much for my spore theory. Ha ha ha. No I think you may have fried something in the ESC. The two sides of the board must share the same ground but it could still overload and feed a few m/volts into the wrong bits I reckon.
 

DennyR

Active Member
Yeah, I have learned this very well in testing performance, If you buy cheap u get cheap, Kontronics top notch, AXI top notch... If you look at the most professional rigs you will see this setup, or Herkules... I'm personally going to try the Maytechs, kopterworxs and almost all the Big retailers support these ESCs, that's always a good sign. Also I have seen them run in person... They get a little warm when running the Big AXI 2826 and so does the motor, but no failures that I have seen.

Also I have heard something about incompatibility with these ESCs and the HoverFly, I will be running Wookong, and these are recommended for this setup. Also Tiger motors are supposed to be good, I will be trying the KW8 as I have an interest in them for more lift, and a cheaper price, sometimes cheaper isn't always better, and don't get me started on Castle Cremations! Def dont use those.
most ESC failures seem to come from caps breaking contact.

If you just paid 600 euros for a Kontronics top of the range ESC then you could be dismayed to find there is a call back on them. Be careful with Tiger Motor pancake motors, the high pole count requires a higher timing than all of the others. Cheapo SuppoMotor 50 Amps work well with those motors. Always make a support for the Caps. (extra Heat shrink).
 
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3dheliguy

Member
Yeah, I heard about the recall, but that's few and far between. The Kontronics that has suffered this recall is the most advanced ESC on the market, and yes it costs a bout load but I'm pretty sure we are not going to be using them. But valid point, I think I would take this risk over anything from China, but I will be experimenting myself.

I will not be using Pancake motors from Tiger I was thinking about 2814 710KV motors from Tiger. I would rather run AXIs, but I'm pretty sure there very close to the same performance and lifting capabilities. I'm also getting KW8 and running Maytech ESCs how do you guys like this?
 

DucktileMedia

Drone Enthusiast
I replaced the esc that was giving me problems. this is a new esc and was still acting up on the same motor it went to. but since the motor works with other esc's I am assuming neither is at fault. Possibly the output of the hoverfly? i dont know.
 


DennyR

Active Member
I replaced the esc that was giving me problems. this is a new esc and was still acting up on the same motor it went to. but since the motor works with other esc's I am assuming neither is at fault. Possibly the output of the hoverfly? i dont know.

14.8 volts back up the red or white wire into the HF would not be good!!! Shades of MK and I2c fireworks..... Sorry mate I hope it is not screwed up.
 
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kloner

Aerial DP
the hf guys might have something for you to check and see if it still works or if have changed colors on the board. it had to pop something, but what.....
 

araines2750

Hexa Crazy
Test this.
Completely remove motor from mount.
With no mounting screws held in hand does it act OK?
Sometimes 1mm too long of mounting screw will interfere with the magnetic field....sometimes in just one of the motors.
Try this and report back.
If it runs good held in hand with not mounting screws, try shorter screws.
 

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