Some advice please guys. I'm busy converting my quad into a hexa, with a few changes along the way. One of the things I want to do is run a seperate 2S battery through a ubec to power the APM2 board, so that I can maintain GPS lock during (main) battery changes. (I am still using the original on board GPS) But I still want to monitor the main motor battery in Mission Planner and OSD. Will the typical setup as described in the wiki work? ie.
Remove jumper, supply secondary battery via ubec to APM input rail, and
Supply APM output rail via ESC bec.
And then a couple of questions....
Will my camera servos be powered via the ESC bec?
One of the mods I want to do is the APM power protection fuse/zener combo. Will I need to do this twice, on both the input and output rails?
Thanks in advance. I did search but didn't come up with anything specifically dealing with these issues.
Replies
If you connect your servos 5V to the middle pin of CH11/CH10 (also know as A10,A11) you will be drawing power from the Inputs PWM power side. I would recommend connecting the power for the servos from the Output PWM and just using the signal lines from A10/A11.
You only need to protect the APM with the Zener and Fuse, so you only need to do it once on the inputs side. I would go for the zener, but not the fuse. That gives you overvoltage protection. Since you are only powering the 'electronics' (APM/GPS/Telemetry and r/c RX) I don't see the need for a fuse as well.
You can connect a simple voltage divider to A1 see link and voltage divider You could use Z2 as 47K and Z1 as 100K+47K+47K gives you a 0.242 * Vin. which is 20V to 5V. That would give you a nice range to measure different size flight batteries. Though I'm need to look into how to set a custom voltage divider in MP