Folks: We managed to get our X8 off the ground (a couple of crashes/cracked props, nothing too terrible), but we did notice that there is no reporting of the voltage to the Pixhawk when we view it in DroidPlanner. Everything is behaving properly. I assume if the voltage isn’t available to the Pixhawk, we can’t use any of the low-battery failsafes. What do we need to do to get this working? I added a low voltage alarm so I’d have SOME indication of it working, but our ultimate plan is running the thing in automated mode, so we really need the failsafe working. Help!
Are you using a 3DR power module or any other voltage sensor?
Wasn’t the X8 2014 supposed to come with it? Maybe they didn’t ship it: store.3drobotics.com/products/3dr-rtf-x8-2014
Specifications:
…
“3DR Power Module with XT60 connector”
I did buy a: amazon.com/Battery-Tester-Vo … B005GJCJOA
–> can that be used, or no?
You didn’t write what X8, RTF or kit… Or how you set it up or even what you used to see the voltage.
With a correctly connected and configured power module, the Pixhawk will know the voltage.
That battery warner that you linked cannot be used as a voltage sensor for the Pixhawk.
Sent from my Ainol Novo 7 Fire using Tapatalk
Hi, sorry, in the previous link I pointed to the RTF (store.3drobotics.com/products/3dr-rtf-x8-2014). To be clear: we bought the X8 2014 RTF model. I didn’t see that voltage module in my box, which is why I was asking! Thanks!
Edit: I’m a bit of a noob, but there are two connectors that are not plugged into anything: the non-power cable coming off the battery – I assume this is what is supposed to be plugged into this voltage module, and what I THINK is the ESC cable. Should the module be already added to the RTF (and I’m missing where to plug it in?)
I strongly advise you to read the user manual and the documentation. Multirotor aircraft are no toys which you just unbox and start flying. RTF also just means that the product doesn’t require excessive assembly. Is does NOT mean, no knowledge is necessary for it’s operation.
Sent from my Ainol Novo 7 Fire using Tapatalk
Stefan:
Thank you for your warning, and I have been taking it VERY easy which is why I’m asking these questions rather than just jumping to running it in full autopilot (which is the eventual goal). We got the thing on and powered up, and armed, which is when I noticed the power wasn’t reporting. This was after spending 2 days just trying to figure out how to program the controller (which was not at all configured for use with the X8 and the documentation was completely lacking). The instructions for the X8 do not talk at all about the voltage monitor:
3drobotics.com/wp-content/upload … ual-V2.pdf
It just says plug it in and you are ready to go. The reason I’m ASKING this question here is because I’m trying to get some feedback on whether I should have received this module and, if I need to order one, how to connect it to the Pixhawk to get it properly working.
Did you check this documentation too? 
copter.ardupilot.com/wiki/common … -with-apm/
copter.ardupilot.com/wiki/batter … failsafes/
copter.ardupilot.com/wiki/table-of-contents/
Ok, the 3DR tech support was able to solve this one. My settings, for whatever reason, were not set to their default (I didn’t change anything in the settings related to the power module). To solve this, I connect via USB in Mission Planner -> Initial Setup -> Mandatory Hardware -> Frame Type -> and restored the default parameters for my copter. Somehow the battery monitor had gotten disabled. By restoring all the settings, the copter started reporting the voltage properly.