RedTwenty
Member
Okay, so I am not having much luck with multi's at the moment
Here is the story...
The other week whilst flying FPV my SK450 Deadcat dropped out of the sky. It was the first time I had flown it for any length of time (i.e. more than one battery). It was flying along happily and then suddenly an arm dropped, it flipped/tipped and I lost control.
Fortunately I found it thanks to the lost model alarm on the KK2.1 and the long grass saved it from any damage. By the time I found it it had sat for at least 30 minutes. After taking it back to the field I checked it over, plugged the battery back in and flew for another few minutes with no issue.
I put that one down to a poorly installed rx and dutifully fixed the antennas to make the most of the diversity signal and range.
Fast forward to today... I took the SK450 out again for a fly. The first time since the above incident. I flew the first battery LOS to check everything out. Second battery I put on the goggle but kept it local and over the long grass. Sure enough after a few minutes an arm dropped, I lost control and it fell like a stone.
This time I found it immediately and checked everything out straight away: Motor 4 was running but had very little power in it. Every time I throttled up the other 3 motors would lift but the craft would tip over motor 4.
I tried replugging the battery to restart the KK2.1 and even re-calibrated the sensors to no avail.
So, now for some quick specs:
Frame: Turnigy SK450 Deadcat quad
Controller: KK2.1 with Steveis V1.14S1 Pro firmware
Motors: Turnigy 2836/8 1100kv with 10x4.5 SF props
ESC: Multistar 20A with latest SimonK (kda.hex) firmware
Battery: 2200mah 3 cell Turnigy
Sherlock Holmes style deductions:
I'm almost certain that what I am looking at here is the ESC overheating. Of course the one thing I didn't do was actually feel the ESC after the crash to see if it was hot.
So, what do I do about it?
The ESCs are already out on the arms under the propwash. Should I remove the heatshrink to aid the cooling? Is it possible to "de-tune" the SimonK firmware or, even better, reload the original firmware to reduce the refresh rate?
Any thoughts or suggestions gratefully received (although I'd rather not have to buy another load of ESCs).
Mike
Here is the story...
The other week whilst flying FPV my SK450 Deadcat dropped out of the sky. It was the first time I had flown it for any length of time (i.e. more than one battery). It was flying along happily and then suddenly an arm dropped, it flipped/tipped and I lost control.
Fortunately I found it thanks to the lost model alarm on the KK2.1 and the long grass saved it from any damage. By the time I found it it had sat for at least 30 minutes. After taking it back to the field I checked it over, plugged the battery back in and flew for another few minutes with no issue.
I put that one down to a poorly installed rx and dutifully fixed the antennas to make the most of the diversity signal and range.
Fast forward to today... I took the SK450 out again for a fly. The first time since the above incident. I flew the first battery LOS to check everything out. Second battery I put on the goggle but kept it local and over the long grass. Sure enough after a few minutes an arm dropped, I lost control and it fell like a stone.
This time I found it immediately and checked everything out straight away: Motor 4 was running but had very little power in it. Every time I throttled up the other 3 motors would lift but the craft would tip over motor 4.
I tried replugging the battery to restart the KK2.1 and even re-calibrated the sensors to no avail.
So, now for some quick specs:
Frame: Turnigy SK450 Deadcat quad
Controller: KK2.1 with Steveis V1.14S1 Pro firmware
Motors: Turnigy 2836/8 1100kv with 10x4.5 SF props
ESC: Multistar 20A with latest SimonK (kda.hex) firmware
Battery: 2200mah 3 cell Turnigy
Sherlock Holmes style deductions:
- Both times the problem happened on the second or third battery used in quick succession
- I am using a battery monitor and at no time did it beep so I can't say a cell died
- The problem disappeared the first time after the model sat for a while but was still present when tested straight after the crash
- I know from my IT days that "overclocking" any processor (which I am guessing is what the SimonK does) can cause overheating
- I just ran the motors up in the garage (now an hour or two later) and the problem is gone again
- It's was over 30 degrees outside on all flights
I'm almost certain that what I am looking at here is the ESC overheating. Of course the one thing I didn't do was actually feel the ESC after the crash to see if it was hot.
So, what do I do about it?
The ESCs are already out on the arms under the propwash. Should I remove the heatshrink to aid the cooling? Is it possible to "de-tune" the SimonK firmware or, even better, reload the original firmware to reduce the refresh rate?
Any thoughts or suggestions gratefully received (although I'd rather not have to buy another load of ESCs).
Mike