FPV wiring harness for board telemetry module

Mike93442

Member
Hi, this maybe, is asking a lot. I’m starting my first Tri-Copter build, and latter on I want to learn to fly it FPV. I am using a KK2 board and not sure of the wiring for the voltage sensor setup to the main power buss. When I do start to fly FPV I plan to ad an on board telemetry module to the video out put to monitor the battery voltage. I’d like to setup my wiring harness in the beginning rather than modify it latter. Can this be wired direct to the main buss, or do I need something other than some sort of plugs in-between?

I hope this makes any senses.

Any help and/or (a wiring diagram :)) would be greatly appreciated
 
Last edited:

RoyBro

Senior Member
Mentor
I think it's a bit premature. All that depends on your camera and transmitter setup. Most OSD modules sit between the camera and transmitter, so the connections have to match. As for power, that depends on the voltage needed by the OSD and what you're using to power the copter. You may need a voltage regulator of some sort to supply the correct voltage.
Figure out everything else first. The OSD can be added later.
 

Mike93442

Member
That makes a lot of scene, I'll just ad a lead to the main buss yo tie into latter for that. OK, can you tell me how does the KK2 beeper get wired for low voltage warnings? I think I'd seen a video somewhere on this but was uncertain what else was needed to make it work.

Thanks again........
 

squishy

Pirate ParkFlyer
I think you should start with a diagram to help us understand what you are asking, we can edit it and help you...
 

RoyBro

Senior Member
Mentor
The voltage alarm on the KK2 board is just a local alarm. It doesn't transmit telemetry back anywhere. The videos show what you need to do so the KK2 board can monitor the battery voltage. Once that's done, you set a threshold voltage in the KK2 settings. When the battery voltage drops below that threshold, the buzzer sounds.

If you want to transmit the voltage level back along video, you'll need an OSD (on screen display) as I described previously. There are some that only provide voltage, but some are capable of providing so much more provided you add the appropriate sensors. It takes video from the camera and overlays its information on top before sending the video on to the transmitter.
 

xuzme720

Dedicated foam bender
Mentor
One other thing on the KK2 voltage monitoring. I found that you only need the positive wire connected to the flight battery power for the board to sense the voltage for the alarm. I had both positive and negative hooked to mine at first, but somewhere along the way I managed to break off the negative. The board still senses the flight battery voltage with no issues. I'm guessing this is due to the way the negative buss on the board is wired.
 

Johan

Senior Member
Makes sense, ground is shared between the ESC (or UBEC) powering the board and that is eventually connected to the same battery.
It might be slightly more inaccurate since GND can start to 'float' if further away from a reference point.
But given the dimensions of a multicopter, it cannot be far off.
 

xuzme720

Dedicated foam bender
Mentor
No, it's not especially since the reference is the distribution wiring to the esc's then to the board. Maybe max 30cm? Still, as long as you can keep everything at the same potential, there should be no float. The main thing I've heard with flight controllers is not to introduce ground loops, but I have to say, the KK2's seem very resilient in this regard...at least so far. But then I am always careful with grounding...