Hello everyone. I hope you are all well.
I am putting together a large octocopter and have come across an issue. A friend purchased the parts for the octo based off a list I put together but OPTO ESCs were ordered by accident instead of ESCs with built in BECs.Unfortunately I didn't notice until now, due to having issues getting the motors and ESCs to fire on the octo, that they were they were OPTO ESCs....the APM would arm ok but the motors would not spin etc. I also ran the motor test in mission planner and the motors do not spin from there either. So I eventually narrowed it down, after many many hours, the ESCs not being powered.
I have not used OPTO ESCs before with the APM 2.5 so I was wondering how I go about powering them?
I believe in order to power the OPTO ESCs I need to use a UBEC or SBEC which must be 5V, how many amps should it be?
Where do I connect the UBEC/SBEC, does it go into a spare channel on the input side of the APM 2.5, a spare channel on the output side of APM 2.5, or into the Rx (I am using a Frsky DR8-II Plus).
And finally, with the UBEC/SBEC attached, should the jumper (JP1) be on or off the APM 2.5?
Thanks very much,
Cameron
Replies
Yes, remove the jumper, power the APM from the Power Module and the ESC's from a uBEC into the output.
A short Y lead is an easy way to couple in the uBEC to one of the outputs if they are all full.
Ok, point to bear in mind is that an OCTO ESC is not the same as an OPTO ESC.
OPTO ESC's have no BEC, so you need to power the APM via the power module (as long as you're <=4S), or via a seperate SBEC.
In all my builds I do not use the BEC in the ESC's but rather a separate uBEC.
How is your APM powered, I am assuming you have the 3DR Power module and the jumper removed from the board.
This means that all you need is a uBEC on the output side as you have correctly assumed.
My large Hexa uses the OS OPTO ESC's like this and all works fine.
The current required is not great and most common BEC's are rated at least 3 Amps which is more than enough, the ESC's requiring only milliamps.