Solved Servo Not Responding on Tricopter with KK2 Flightcontrol Board

[Trevor Gallant]

I made a tri-copter a few years back following David's tutorials on Flite test and setup the KK2 board using the video on his channel. However, neither video goes into detail about how to connect the ESCs to the flight controller board. I've read that in order to provide power to the board, I need to connect the ESC of my M1 to my power source and then to the board (three-way connection). Unfortunately, this does not seem to provide power to my servo in M4. The other method that I tried and that I think I had when I first made this tri-copter was to connect a spliced wire from the power source to M1 and to M7, then have the motors 1, 2, and 3, and the servo in M2, M3, M3, M4, respectively. I'm not sure if that is what I used on the past but it did work at one point and the servo got power. The reason why I am not using that method now is that the servo seems to just continuously turn in one direction once it receives power. As of right now, I have the ESC for my motor 1 connected to my power source and to M1, but as I said earlier, the servo does not appear to get power. Does anyone know how to fix this problem? Let me know if you want a photo or anything.

 

[LitterBug]

I have two KK2 boards that came with a large Tricopter. Never flown them, but I did play with them on the bench recently. There is a seperation of power buses supposedly to keep the servo from being able to brown out the FC if it exceeds the current capacity of the BEC on the ESC. M1 only powers the FC and not the rest of the M2-Mx pins. You will need another BEC or a Y to the other bus to power the servo.

LB

 

[Merv]

I need to connect the ESC of my M1 to my power source and then to the board (three-way connection).

I have not looked at a KK board for a long time.
If I recall M1 powers the board. The positive & negative pins on M2-7 are on a separate rail. To power a servo, you need power to any one set of the pins M2-7. Don’t use the same power source for the board to power a servo. The servo will cause too much interference and destabilize the board.