I have the 3DR power module supplying the input side of the APM 2.6 with it's requisite 5 volts. I have some LEDs and video switching gear that I also need to connect that require 5v. Clearly relying on the the APM 5v provided by the power module is not wise. So I have a 5v BEC to provide 5v to accessories. Sounds straight forward. But then I got to thinking. Could I just hook this 5v BEC output up to the APM input rail as well? That would put this external 5v BEC in parallel with the 3DR power module's 5V BEC. This would solve the overload problem, and at the same time provide redundancy. If the power module goes up in smoke, the APM would not lose power.
So short version, is it ok to have a parallel source of 5V feeding the input rail along with the 3DR power module?
Replies
You need some Schottky diodes to create a switch over.
Easiest solution for redundancy is to buy a $30 device called a Batshare. https://www.smart-fly.com/Products/BatShare/batshare.htm
Otherwise, just use the ESC BEC for the lights and other gear.