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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Could you diagram that for me? I'm having a hard time seeing how everything would be connected.

Ordered a castle creations BEC. I have a rudimentary plan now.  I will post a diagram when i am finished so it can be double checked.

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.

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.

Yes, I agree. 

It would be extremely helpful for an "expert" to show some general and specific wiring diagrams with photo's showing the various possibilities of powering the APM2.

Some notes and/or warnings with a few of the key  "what not to do" for the most common mistakes would also be very helpful. 

Forgive me if one has allready done the above, sometimes I get lost in DIYDrones trying to find specific answers to these questions.  Please point me in the right direction if we have allready explained this in great detail.

At $200 a pop (pun intended :) , I'd rather spend those dollars buying more fun things from DIYDrones.


Richard Eis P.E.



It's a bit tricky because you can do many kind of power connection.

1. Power from USB

2. Power From ESC

3. Power from BEC + ESC 

4. Power from USB + BEC/ESC

5. Power from BEC + BEC

Some of them will fry something. What will be you will see. Can be AMP or can be USB, or BEC .

Powering isnt explained well in wiki docs and many new user of AMP can get lost in pages looking for a valid information.

1. Power from USB 

JP1 OFF and dont put any power from ESC/BEC on IN V+ will fry the USB 

Can use radio modem AND can power the telemetry / OSD but ony power last 2 because cant comunicate with them as long usb is linked. (Didn't try to just give power from usb because is clean 5v and dont link D+ and D- from usb but im sure will switch SERIAL 0 to USB and cant use as data line the Serial0 RX and TX.

If you need to test your motors and/or servo you will need to go in case 3,4 and 5 when you connect the second power on the OUT V+ line (just ONE if you have many ESC or BEC)

2. Power from ESC/BEC


Cant connect USB will fry it or some power line will get burn in case you usb dont die first.

This case is used usual with only 1 LiPo for all you got connected to AMP 2 and when you are away from PC.

Dont care wher you put the power on IN V+ or OUT V+ is up to you where is more easy.

3. Power from BEC + ESC 


Powering from BEC connected to the same battery or separate battery is used to get a proper 5V to your AMP2 and your radio.

OUT V+ will get power from ESC (if is need another power for the servo who require other than ESC power will supply that power to the OUT V+  case 5). It can be use a second BEC with other than 5V or even with 5V but with more power to drive all your servos. In this way servo wont affect the 5V from AMP + Radio and/or Telemetry + OSD.

4. Power from USB + BEC/ESC


This is used to test/set AMP2 and is connected to PC via USB and can test radio and motors / servo who will get power from OUT V+ who will be supply from BEC/ESC.

5. Power from BEC + BEC


This is use for separate the power of AMP (fragil electronics) from Servo. Is good when you have 2 battery also the separation is more complete in this case but can be used with 1 LiPo too.

I guess on other case to powering the AMP can be.

PS. You can see the JP1 is need only 1 time when all get power from 1 ESC/BEC and dont CONNECT USB EVER

1. Power from USB  = JP1 OFF

2. Power From ESC/BEC = JP1 ON

3. Power from BEC + ESC = JP1 OFF

4. Power from USB + BEC/ESC = JP1 OFF

5. Power from BEC + BEC = JP1 OFF

I hope some one will find this value

Just read the message I just posted will make some linght on the powering AMP and others.

I think a little drawing and maybe some photo's would help a bunch :)


APM 2.0 sounds horrible to power up. Did the APM 1.0 have similar issues?

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

What 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.

I suppose I should add a disclaimer...

I haven't received my APM2 yet, it's with FedEx.

I'm not 100% sure the USB power will power a receiver.

I didn't include advanced setups like dual BECs or quad setups with multiple ESCs, but advanced users can work those out easily enough. (Only one +5V supply for each rail)

With USB only you should be able to get power to the Output rail via JP1, although it probably wouldn't be enough milliamps to power a servo.

thank you for the diagram

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