OK. This is bizarre.

I took the motor off and checked for any obstructions, cracked motor mount etc. ; nothing out of the ordinary, so I put it all back together.

Then I programmed LOW ESC timing. It worked! Full throttle no problem. 16.8 amp draw.

Of course, I had to see what a MEDiUM setting would do. It worked too, but the amps were slightly higher at 17.4.

OK. I just HAD to try HIGH to see if the problem repeated itself. No, it worked again!

That didn’t make sense, unless the ESC and motor pins weren’t fully connected earlier. I wiggled all the wires around but the motor ran fine every time with about 19.2 amp draw at full throttle.

So, it looks like the mechanical connection between the ESC and motor was to blame?

I took the Radian out and flew it briefly as the sun was setting.

Think I might fire up the soldering station and resolder those pins, just for good measure.

The ESC has a small Flash memory (the same thing that's in your phone/tablet or SD card) to save settings when it's powered off. Flash memory is not non-volatile. The data it contains can simply fade away with time. Normally you'd be talking a decade or so. But retention time decreases with use (Flash wears out), and storage at high temperature accelerates the rate of "data loss" (lowers SNR, increases error rate). Also, off-brand manufacturers might be buying lower-grade components for the cost, so maybe they're not high margin parts to begin with.

But also, the part has to be initialized to its defaults and maybe it wasn't, so the parameter that controls timing might have had some random/inappropriate value until you re-set it to something correct.

Which is why I said "It's possible the ESC timing is wrong, so it's worth trying that." in reply #7!

If the problem comes back after a while, it's because the Flash on this ESC is low-retention (technical term is "crummy"). If it never comes back, my guess would be that it wasn't initialized to its defaults correctly when it was manufactured.

Thanks for the explanation. If this happens again, it might be time to ditch the ESC.

Originally Posted by mybad

That didn’t make sense, unless the ESC and motor pins weren’t fully connected earlier. I wiggled all the wires around but the motor ran fine every time with about 19.2 amp draw at full throttle.

So, it looks like the mechanical connection between the ESC and motor was to blame?


Think I might fire up the soldering station and resolder those pins, just for good measure.

Told ya !

I’m still wondering why I would have gotten such an extreme amp draw due to either an ESC problem or a poor connection problem.

I do have a hard brake set up, if that’s pertinent.

I worked in electronic engineering for over forty years.
We had phrase for this kind of thing happening - - Electrical Phenomenon.
And it happened often. .