I've posted this issue in the RC Groups forums as well but I figured I'd ask here too. Hopefully someone can spot something stupid that I'm doing or something obvious that I'm missing, or maybe it's just some electric gremlins doing their handy work.

This is the first quad I've built and I've managed to fry 6 ESCs so far , and they aren't exactly the cheapest things haha...

I've been testing things as I go on the bench, making sure the quad powers up (with the SmokeStopper) and the motors spin when armed, and responds to the transmitter just fine.

I did some hover tests and it seems to hover just fine, however, the problem seems to be that the ESCs fry too easily and instantly fry themselves if the prop strikes the ground. I've managed to do this twice, the first time frying one ESC and the second time 2 ESCs in one go. When they're "fried", all they do is get hot when the battery is plugged in, even when not armed and they no longer get detected in BLHeliSuite32.

Here's a video (please forgive the portrait orientation) of a hover test where I managed to fry an ESC attached to motor #3, the bouncing when it lands is probably due to my DIY landing pads being a bit too squishy (which I have gotten rid of) and the FC trying to compensate as I'm in Horizon mode:



I was initially running off a set of Aikon AK32 35A 2-4S ESCs but when I went to purchase some replacement ESCs the 4S version was out of stock so I just picked up a set of 6S versions of the Aikon AK32 and now running on those.

So after fitting those 4 new Aikon AK32 6S, I managed to fry yet another 3 of them, this time in mid-air, I think...

It was flying just fine in Stab mode, I then flicked it over into Acro/Air mode and everything went well until I tried to do a pitch flip backwards and instead of just a single flip it went crazy, spun out of control. I'm assuming that for some reason the FC sent too much current to ESCs attached to motor 1, 3 and 4 and fried it which made it flip out of control, but that's a wild guess and I honestly have no clue.

I tried to disarm it before it hit the ground as the previous 3 ESCs (possibly) fried due to prop strikes, and by looking at the log and the DVR it seems like I did disarm it before it hit the ground, but when I went to pick up the quad and rearmed, the ESC on motor 1, 3 and 4 were dead, hence my guess that it fried mid-air.

Check out this video of the DVR + Betaflight Blackbox log overlay for what happened:



I've attached an image of the exact moment where motor #3 strikes the floor from the first video, what my FC and ESC looks like with all the wiring, what my whole quad looks like, the blackbox log for the first hover test video, CLI settings, as well as another blackbox log for the flight where it flipped out.

The ESCs are hooked up to T-Motor F40 III 2306 2400KV motors with tri-blade 5046 props and running off a Matek F722-SE AIO F7 FC on a 4S battery. For all the bits and bobs in my build, you can check out the comprehensive list here: https://rotorbuilds.com/build/17592

I definitely don't feel like ESCs should be frying this easily and should be able to hold up a bit better, there must be something else going on here. Can anyone see something wrong that I'm doing, or is my Flight Controller borked and asking the ESCs to do much? Or I have 4 wonky motors? Though I somehow doubt that.

Appreciate any help or advice anyone can provide!

probably the link to rc groups forum, prevent before wasting time with the same solution possibilities...

your problem sounds terrible, did you config anything with blheli - rumpup or specially current protection. probably could be healthy for budget to try with more current protection: but not a reason...

i cannot read logs.. what battery do you use? if to heavy or give more power than your cables - your circut can handle...
i would check all basics of the build, every hardware; solderpoints, transisotors, cables - it sound that strange to me with this quality escs, i probably would desolder and rebuild again with high attantion about. a try with another cheap fc seems to be aswell a cheap option, as you allready fried money on the bench.

(11-Jun-2019, 02:47 PM)hugnosed_bat Wrote: probably the link to rc groups forum, prevent before wasting time with the same solution possibilities...

I did link to the RC Groups post, guess it's not prominent enough haha, I'll make it so

(11-Jun-2019, 02:47 PM)hugnosed_bat Wrote: your problem sounds terrible, did you config anything with blheli - rumpup or specially current protection. probably could be healthy for budget to try with more current protection: but not a reason...

I didn't change anything in blheli besides motor direction to reverse them since I didn't cross my motor wires, everything else I left as default

(11-Jun-2019, 02:47 PM)hugnosed_bat Wrote: i cannot read logs.. what battery do you use? if to heavy or give more power than your cables - your circut can handle...
i would check all basics of the build, every hardware; solderpoints, transisotors, cables - it sound that strange to me with this quality escs, i probably would desolder and rebuild again with high attantion about. a try with another cheap fc seems to be aswell a cheap option, as you allready fried money on the bench.

I'm using a 4S 1500mah battery and I've basically desoldered all the power and signal wires to the ESCs at least twice as I was replacing them but I'll do another inspection of all the soldering points and prod with the multimeter and check for shorts. Getting another FC to test is definitely a good idea, I will see what I can pick up, thanks!

I'd be interested to see if my quick response (guess) is the same as on RCG. Your hardware looks good and compatible. I'd be looking at a FW/PID/filter issue. What version of Betaflight are you using on your flight controller, I know there were some issues with F7 FC/32bit ESC with the earlier versions of BF 4.0.

true you linked at the top x-) sry

what i mention, the incorrect firmware for the fc could cause strange things. a few days ago someone was hopless, motor 4 didnt work on two quads... reflash fc again, could be anyway a reason...

(11-Jun-2019, 03:25 PM)RENOV8R Wrote: I'd be interested to see if my quick response (guess) is the same as on RCG. Your hardware looks good and compatible. I'd be looking at a FW/PID/filter issue. What version of Betaflight are you using on your flight controller, I know there were some issues with F7 FC/32bit ESC with the earlier versions of BF 4.0.

It's running BTFL 4.0.2 and haven't touched my PIDs at all besides RC Rate and Super which I've set to 1.5 and 0.8 respectively on all 3 aspects, and neither have I touched the filters – they're all Betaflight defaults as I did a reset before configuring everything.

(11-Jun-2019, 03:26 PM)hugnosed_bat Wrote: true you linked at the top x-) sry

Heh, all good, I initially only put the link on a single word so that's why you may have missed it haha.

(11-Jun-2019, 03:45 PM)hugnosed_bat Wrote: what i mention, the incorrect firmware for the fc could cause strange things. a few days ago someone was hopless, motor 4 didnt work on two quads... reflash fc again, could be anyway a reason...

I haven't touched the firmware at all and have just used whatever came on the FC, which also seems to be the latest version as I did check for updates before configuring everything.

I have the exact same issue, with the same combination FC-ESC: Matek F722-SE and 4 single Aikon AK32 35A 4S ESC's. Only.. 2 years later it seems.. Same products, but firmwares have moved on.

The drone flew ok for 15-30 seconds during very slow test flight (1m high, navigating a bit in all directions and then normal landing). The next time I tried to fly, one ESC was broken. I replaced it and did a second test flight. Drone was flat on the ground, very slowly raising throttle and an ESC broke before the quad was off the ground (it was near liftoff as it was wobbling a bit already).

Did anyone ever find out what was going on? What could we be doing wrong that the ESC's break so quickly?

(07-Apr-2021, 08:00 PM)NickOostende Wrote: I have the exact same issue, with the same combination FC-ESC: Matek F722-SE and 4 single Aikon AK32 35A 4S ESC's. Only.. 2 years later it seems.. Same products, but firmwares have moved on.

The drone flew ok for 15-30 seconds during very slow test flight (1m high, navigating a bit in all directions and then normal landing). The next time I tried to fly, one ESC was broken. I replaced it and did a second test flight. Drone was flat on the ground, very slowly raising throttle and an ESC broke before the quad was off the ground (it was near liftoff as it was wobbling a bit already).

Did anyone ever find out what was going on? What could we be doing wrong that the ESC's break so quickly?

Dude, this thread is like 3 years old... just sayin'

Surely qkevinto got his issue resolved although it does not appear to be posted.

Here are some of my thoughts on the subject.

We will likely never know if the OP's problem got resolved because unfortunately his/her last visit to the forum was on 24th June 2019. It's also possible that he/she has since left the hobby which is maybe why they haven't been back since.

That sucks. It was proly something simple like using a 12amp ESC with 2207 motors or something.

Edit: Yeah looks like he's running 32 amp ESC's with 2306 motors on a heavy looking quad and proly no Cap. Depending on how heavy that quad is it looks like he's simply over working the ESC's, and it shows as soon as he increases the throttle to do a back flip.

32amp ESC's for a 5 inch with 2306 motors.... and depending on the batteries as well, just seems like not enough especially without a cap.

(08-Apr-2021, 12:53 PM)iFly4rotors Wrote: Surely qkevinto got his issue resolved although it does not appear to be posted.

Here are some of my thoughts on the subject.

Yes, on another forum I also found him. There he said it was solved after replacing the FC (with same type Matek F722-SE) and other ESC's (from Aikon AK32 35A to Spedix ES30 V2 HV 30A ESC's). So he even lowered in A and still managed to fix it.. so far, unclear why the Aikon's failed..

(08-Apr-2021, 02:11 PM)NickOostende Wrote: Yes, on another forum I also found him. There he said it was solved after replacing the FC (with same type Matek F722-SE) and other ESC's (from Aikon AK32 35A to Spedix ES30 V2 HV 30A ESC's). So he even lowered in A and still managed to fix it.. so far, unclear why the Aikon's failed..

Hi NickOostende,

If you have to replace everything anyway, I would consider getting a stack with an FC and a paired ESC 4-in-1 board rather than individual ESCs on the arms. These stacks work very well, are easier to wire, and easier to assemble. In fact, most of them come with a cable so that connecting the two boards is pretty easy. Then, you just solder the motor wires to the ESC board, done. It also makes for a cleaner build. Just a consideration 

Hello! Sorry I never posted the solution here, I posted in the other post on RC Group which saw a bit more activity and must’ve forgotten about this thread.

But as Nick noted above, my “solution” was just getting a brand new Matek F722-SE FC and replacing the ESCs with Spedix ES30 V2 HV 30A (though mainly because the Matek ESCs were out of stock at the time). I would assume the issue was with the Matek FC itself being faulty or (more likely) I screwed something up whilst soldering everything up the first time, hard to say though.