Powering the Ardupilot Board


I am completely new to the world of hobby UAVs so apologies if this question sounds a bit trivial, but any help on the matter would be greatly appreciated.

I recently purchased a new ardupilot mega and oilpan. After soldering and downloading the software I am keen to connect my RC gear and get going, but am terrified of doing it wrong!

Firstly should I connect my receiver to the input channels on the Mega Board, and then connect my servos to the output channels.

However, if I then put attatch my battery and motor to the ESC, and connect that to the output channel of the Mega Board, will that operate correctly?

Again, apologise for the probably trivial question, if you need any additional information please comment.


Charles Winter.

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  • Dear 

    I need to know that i am not using power module and i want to power my APM 2.8 correctly 

    the JP1 is ON and i am connecting all three pins (s,+,-) of my ESC BEC (5v,2A) to output pin 1 and for all other ESC's i am only connecting the signal wire because power from output pin1 will energize the complete output rail thats why for o/p pin no 2,3,4 i am only connecting white signal wire. but on interneti i have seen so many people connecting all three wire of every  esc to the ouput rail why they are doing this because they can power output 1 and for other other escs they should remove the +ve and negative  

    and the same method i am using to power my reciever here i am connecting all threee wires (S,+,-) from input 1 to channel 1 of my RX. and for other channels i am only connecting the signal wire. so tell me that every thing is ok with my powering method .... Or tell me that if i use power module and remove the jp1 than for powering output rail i should use the same method or not .....  

    UAgroV said:

    Hi Charles,

    your APM2 comes with a jumper (JP1) as shown here:


    if its "On" your whole equipment would be powered by the output rail, normally from the ESC in chanell 3. Thats meens, all the power pins in output rail, all the power pins in input rail and APM will be in parallel, so the servos conected to output pins, your radio receiver conected to input pins and your APM will be powered by de motor ESC. This is the case you described so Yes, it would operate correctly.

    If Jumper is off (open) your servos will operate powered by the ESC as allways, but your radio receiver and your APM2 will need another battery. It could be usefull for example if your motor and servos battery get empty and your aircraft couldn't return home you would be still having telemetry and position of it. Im sure there are many more cases but i dont imagine them.

    Hope it will be usefull for you.

    Have a nice fly.


    Powering the Ardupilot Board
    Hello. I am completely new to the world of hobby UAVs so apologies if this question sounds a bit trivial, but any help on the matter would be greatly…
  • Hello everybody,

    While the APM2.5 is already available, would be great if somebody could refresh this topic. What are the major changes regarding the powering on this board? Everything which was described here is valid for the new board too or we have now more flexibility to choose the combination?

    If the board is powered through the output rail (as usual), due the built-in Schottky diode which must prevent to burn something when also the USB cable simultaneously is connected, it is an voltage drop on the Input rail which is relative low for the connected Weatronic receiver. Have anybody ideas how could be this issue solved?

    I think the remaining solution is to power separately the receiver through a second ESC (by multirotor) or using a BEC but only the ground will be remaining common for the entire system. Other tips are welcome.

    Thanks in advance,


  • I've got the APM1 board and IMU (oilpan).  I can see the solder pad which can be de-soldered to separate the ESC/servo common +V rail from the +5V supplied to the APM board.  The separate connector to power the the APM is near that solder pad and it apparently needs between 7-10v.  Can I use a UBEC on those pins even though it will only feed 5V or is there some other point on the APM or IMU board I should feed the +5V to the APM/IMU?

    I'd rather not have a separate two cell LiPo for the APM power.  I just need a 6V BEC on the ESC/Servo common rail and a 5V BEC to drive the APM with one source three cell battery.  That way I can run my camera stabilisation servo's at 6V (faster response).

  • With JP1 OFF, using a separate battery/BEC for the input side, which rail are the camera pitch/roll servo ports (A10, A11) powered from?

  • A few people requested a diagram to explain the power options. Based on DahaS's post I created this...

    ardupilotmega20powercon.jpgWhat I have learned creating the diagram:

    JP1 connects the input and output power rails.

    Connecting +5V from a power rail to the USB will fry it.

    So basically you must not have ESC/BEC power running to the Input rail, either directly or via JP1, while you have the USB connected.

  • Thanks to all for these replies...i have posted in a couple other discussions these general questions.

    I too would like to see a very general wiring diagram (perhaps im more of a visual learner!). In theory i think im starting to grasp what is required in terms of powering...but again like other newbies the concern of frying the board outweighs experimentation at this point.

    I hope contributors here continue to elaborate. It is very helpful.
  • I'm not sure what the problem is.  Perhaps you have a bad board.  Mine powers up just fine from either the input or output.

  • I'm having a bit of a different issue and could use some clarification on how to power everything.

    In my case I am use a large servo that requires 6v or 7v and my Castle Creations Phoenix Ice 50 BEC is programmed to output 6v accordingly.

    So I need 6v to my servo.  I don't really want second battery right now. Can somebody diagram for me how I might set this all up for use with the APM 2.0 + telemetry.



  • I'm also a beginner. For the initial phase, I want to  use the board only as a datalogger which will get the sensors and GPS readings of several manually flown air vehicles. Please correct me if anything is wrong with what I think:  Board must have its separate battery. Also I don't need servo power so I will leave the jumper off. In order to power up sensors processor and sdcard  which pin should I connect the 5V supply? Thanks. 

  • Does the APM 2.0 have a built in LM317 regulator like that APM1.0 for external power supply?

This reply was deleted.


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Aug 25