I have a Pixhawk Cube Orange running ArduPlane firmware. All my servos and the ESC are connected directly to the MAIN OUT ports. Each servo works fine when tested individually. However, when I connect all servos and the ESC at the same time and try to control them via Mission Planner or the RC transmitter, only one servo works properly; the others do not move, and the ESC receives no power.
What could be causing this issue, and how can I fix it?
Also, if I need to add a UBEC or use the ESC’s SBEC properly, how exactly should I connect it to the Pixhawk? Should I connect the 5V to the servo rail directly, and how can I do it safely?
The servo rail is not powered, so yes you need to add a some kind of voltage supply. If the BEC in the ESC is rated enough for your servos then that’s probably the simplest. It’s probably already on the 3-wire dupont plug for the ESC signal so just plug that in and whenever there’s battery power to the ESC you should be good to go.
The ESC is already powering the servo rail since it has an integrated SBEC. The 3-wire Dupont cable from the ESC is connected to the servo rail, so the servos are getting the required voltage from there.