XAircraft For the love of,,,

[Tomstoy2]

Dang nab it!

Took the Hexa out for a romp, fired up,,, and #5 motor won't spin up. I see it arm, but no spin up.
Perfect weather, too! 75* F, 2 mph wind, go figure!

Don't believe it's a motor thing, got to be an esc. Everything is still plugged in, nothing loose. I use mt2216-900's and Tiger 30a esc's.

At least it happened on the ground.

Still, I wonder if it could be something with 5.06 firmware upgrade, as last Saturday I did a few flights with it and immediately noticed a difference in temp's. Wouldn't say it got hot, but they always ran just slightly warm before, and I had to guess I would say the new firmware raised the temps up probably 30* F.

Going to have to swap the motors to confirm it's the esc, or not. However if it is, I will deffinately load back up the old 5.02.

I do know that my first flight with the new firmware was rock solid, no wind. Later that day, the last flight, the wind picked up, which pleased me as I wanted to see how she behaved in wind. In gps she toilet bowled in a lazy 3-4 foot circle, which puzzled me at the time. Could have been the esc acting up and I got lucky.

Dang nab it!

 

[Tomstoy2]

Well, it's the esc. Just got done troubleshooting everything. Got another comming sometime Monday.

" So Tom, how do you troubleshoot an esc?", you may well ask. Well, let me tell you.
Now you heli guys are limited, unless you have spares on hand. I however, have 6 times of everything on my Hexa, which symplifies troubleshooting,,, only. Remember, 6 times of everything also means 6 times the potential of something going wrong. These things don't auto-rotate at all so care must be taken anytime you fly.

First, I started by swapping the troubled eec connector, ( #5 esc ) with the # 6 on the WKM motor controller.
The problem stayed with the motor regardless of the port, confirming that the motor controller port was just fine.
I then put the #6 esc into the #5 port as a double check. Sure enough, the #6 worked just fine in #5 port.

Next, I disconnected the #5 and #6 motors and swapped them. The #5 motor on #6 esc spun up just fine, confirming that the # 5 motor was fine. Pretty much pointing to the #5 esc was the issue.
As a double check I put the #6 motor on the #5 esc. It wouldn't spin up, thus totally proving something was wrong with the esc.

As I have my esc's all attached to the inside of the frame halves, I then needed to remove all the bolts attaching the top frame to access the esc's.
Here is a little trick I'll give you, which will apply to any build, whether a single rotor heli or a multi-rotor like my Hexa. When you start your build, if you have any button head bolts, throw them out, use only socket-head cap bolts. Button heads don't have much 'beef' to them making them prone to strip out when you need to remove them. Also, don't over-torque the bolts, trust the loc-tite to do it's job.

Then last, I placed a meter across the positive and negative leads connecting the esc, powered back up and confirmed I was getting full voltage.

When troubleshooting, you really don't want to miss any of these steps, if you do you risk missing the 'root cause' of the problem and re-introducing it later when the affected component is replaced.

Once the #5 esc was removed I cut off the heat-shrink from it, removed the heat sinks and examined the esc for any bad solder points. I didn't find any so something on the esc failed.
As I said before, the esc would arm, I could see the motor do it's little tweak thing when arming, but wouldnt spin up. Somehow, one of the components on the esc now fails to push voltage to the motor when the throttle advances.
If I was an electronics guy, I could then track the problem to the component and then replace it, maybe, thus saving the esc, but I'm not. I work as a controls specalist, but my extent of repairs is to eleminate the problem board, not the individual component. Plus, at my age my hands are not steady enough to do fine solder work on tiny boards anymore.

I hope this helps you new builders out in understanding how to troubleshoot electrical issues that plague us all at one time or another.