DJI Zenmuse Z3 Pinout
As stolen from http://cosmostreamer.com/wired/howtomake, I would say it is safe to assume that it is indeed power+ and power-. The images are not directly from the zenmuse but from the Inspire adapter, which I think is perfectly compatible with the zenmuse 3 as taken from the site 


  Flying with the Zenmuse Z3 is as simple as attaching it to the DJI Inspire 1