F550 T-Motor fault

[fabiolr]

Hi Everyone

My new F550 crashed on its third flight. I could see it lost power on one motor. At first I thought one motor cable came off from the ESC, as this was one obvious possibility since a cable was disconnected after the crash.

So I replaced the one broken arm and prop, and fired it up for a test.

Surprisingly, one other motor would not work. Not the one that had the ESC cable off post-crash, nor the one with the broken arm/prop.

This may be what caused the crash in the first place.

I built this hexa to be very reliable. I used T-motor Motors, T-Motor ESCs and T-Motor CF 10x3.3 Props. And I built it carefully.

So I am intrigued by this fault.

The engine seems OK, as it seems to turn back and forth (Cw and CCw) rapidly.

I suspect it is an ESC fault.

Has anyone seen this before? Bew T-motor esc fault?

Here is a video of the failing motor:
http://www.youtube.com/watch?v=d4utIi4_HLo

I ordered a new motor and ESC To test, but I am curious if anyone had this before.

The only thing I am guilty of is that the aircraft was very heavy. It has a Zenmuse, GoPro, and a 11000 3S Mah maxAmps LiPo. But it flew nicely and didn't seem underpowered, and was hovering when failed.

Thanks!!

 

[AEA737]

Sorry for your crash.

What was the weight of your F550 fully loaded with that 11.000 Lipo? I used to fly my 2.4 Kg F550 with a 6000 3S and was underpowered. I switched to 4S.

Javier

 

[fabiolr]

About 2.6 kg.
It seemed allright, though I didn't fly long before the crash. It was the 1st time I was flying with the 11.000 Lipo. Before I was using a 5000 and was just under 2.4.

I got the 3s based on ecalc, for my 10x3.3 T-motor props. I got the 4S for the smaller props, but didn't have the chance to try them.

Fabio

 

[W. Reimer]

I've never seen that specifically before, but it's certainly not impossible. It sounds like you had things well thought through, you had the right props...I don't think I'd do anything differently; I'd be suspicious of the ESC's too. Curious to hear what you find out definitively.

 

[fabiolr]

I've never seen that specifically before, but it's certainly not impossible. It sounds like you had things well thought through, you had the right props...I don't think I'd do anything differently; I'd be suspicious of the ESC's too. Curious to hear what you find out definitively.

Thanks Reimer. I have ordered new ESCs and motors. Will post when I find out what went wrong.

 

[fabiolr]

The motor was faulty. I put in a new one and it is fine. ESC also OK.
Very disapointing for a brand new T-Motor.

 

[SoCal Blur]

Could it be that one of the mounting screws went in too deep and broke a wire in one of the windings?

 

[fabiolr]

Could it be that one of the mounting screws went in too deep and broke a wire in one of the windings?

I inspected under the screw holes carefully with a magnifier and could see no damage. I used the original DJI F550 screws, which don't seem to be long enough to cause that damage.