All four motors stop at the same time during flight

[Asaad_civic99]

Hi,

I have an HK AIO board (Crius V1.1 clone) running mutliwii 2.4 firmware. I have encountered 2 incidents where all 4 motors just stopped in mid flight. On the 1st time I was testing the Alt hold function and the 4 motors stopped while the copter was going up. On the 2nd time I was on Horizon mode and climbing. My board has external power fed to it through a UBEC which powered by one of the flight batteries (I use 2 x 2200 mah 40c).
So I thought there is a drop in voltage that causes the UBEC to not supply the board with enough voltage.
So i used a separate battery for the board. It did not fix the problem as I encountered the same problem again.
I have noticed that the voltage of my flight batteries is around 3.75 -3.8 volts per cell after each crash.
What could be the problem?

[Revs]

That voltage is fine. The battery is flat and was ready for landing, but not too low.

Sounds like you may have the low voltage cutoff enabled in your ESCs?

[annikk.exe]

Could it be failsafe kicking in?  Perhaps there';s a dodgy connection between RX and FC.

[Asaad_civic99]

That voltage is fine. The battery is flat and was ready for landing, but not too low.

Sounds like you may have the low voltage cutoff enabled in your ESCs?

I have 4 x 25-30 amp hobby king ss series ESC, The quad copter would fly fine until the buzzer sounds with no problems. I will check anyway and report back.

[Asaad_civic99]

Could it be failsafe kicking in?  Perhaps there';s a dodgy connection between RX and FC.

I fly an old FM transmitter with no failsafe what so ever. As for the connections between Rx & FC I also do not suspect that all four ESC connections to the board fail at the same time. I will check anyway.

[annikk.exe]

I fly an old FM transmitter with no failsafe what so ever. As for the connections between Rx & FC I also do not suspect that all four ESC connections to the board fail at the same time. I will check anyway.

I was thinking more that if the FC stops seeing a signal from the RX, it might have its own failsafe.  As far as I know on my 250 there is a failsafe on both the RX and the FC.  The RX one kicks in if it loses signal from my TX.  The FC one kicks in if it loses signal from the RX.

[pheasant_plucker]

Are you using a Ubec or powering the flight  controller from the esc bec? Your posts aren';t clear on this.

Gerry

[forest]

That voltage is fine. The battery is flat and was ready for landing, but not too low.

Sounds like you may have the low voltage cutoff enabled in your ESCs?

i would say the same as revs they have the low volts cut of turned on and set at the voltage that you see being the same every time ? if you look at george7 post in the posts under the product he tells you how to change the settings here http://www.hobbyking.com/hobbyking/store/__6458__Hobbyking_SS_Series_25_30A_ESC_card_programmable_.html