My favorites | Sign in
Project Home Downloads Wiki Issues Source
Search
for

ArduPlane Instruction

June 2013 UPDATE: The ArduPilot manual has now moved here. The manuals here are for legacy hardware and will no longer be updated or maintained.

APM25Power  

zh-Hant , en
Updated May 27, 2013 by billbon...@gmail.com

Alternative ways to power your board

3DR Power Module

If you are using the 3DR Power Module please find instructions here: http://code.google.com/p/ardupilot-mega/wiki/Voltage

Power Requirements Summary

Single Supply

Power Options Nominal Abs MAX JP1 status
Power on Output PWM connector 5.37V +-0.5 6V JP1 connected

Dual Supply

NOTE: if JP1 open, power is required on both Input PWM and Output PWM
Power Options Nominal Abs MAX JP1 status
Power on Output PWM connector 5.00V +-0.5 6V JP1 open
Power on Input PWM connector 5.00V +-0.25 5.5V JP1 open

Warning: Do not exceed Abs MAX input voltages when connecting power supply or you will damage your board.

Warning: Connecting USB when you have input voltages at the high end of the range (near Abs Max) can damage the board. Disconnect battery before connecting USB or test input voltages so they are within the normal specified range.

On the bench, you'll probably be powering the board via your USB cable while you set it up and test it. But in your aircraft, you'll need to power it with your onboard power system, which is usually your LiPo battery going through an ESC. In the case of a multicopter, this will probably come through your Power Distribution Board (PDB), which will break out the 5V output from the one of the electronic speed controls (ESCs).

In the picture below, the red and black wires are the 5V power cable coming from a PDB. You can plug them into any two pins along the 5V and Ground (middle and outer) rows of pins on APM 2.5's Output side. The other cable, which in this case is a four-wire cable with orange and white wires for a quadcopter, is the signal cable to the PDB, which are the wires that APM 2.5 will use to command each of the ESCs.

The picture below is of APM 2; but the concept is applicable to APM 2.5.

It's also possible to power APM 2.5 from two separate sources, one powering the RC system on the input side, and the other powering the output side (servos or ESCs). This is determined by a jumper on the JP1 pins (see below). If the jumper is on, the board is powered from the Output rail or the USB. If the jumper is off, the board is powered from the Input rail, but the Output rail will need its own power source. This configuration is used if you want to have two separate power sources in your aircraft, one powering the servos and the other powering the electronics.

The ideal voltage on the Outputs is 5.37v +/-0.0v and may not be provided by a typical ESC.

Warning: Do not exceed 6.0V DC of power supply input voltage or you will damage your board.

In some cases it may be a good idea to set the input voltage slightly above the median (but below the maximum) to account for possible voltage drops during momentary high current events.

The APM2.5 by itself draws relatively little current (200ma range) and a power source capable of providing 300 - 500ma will provide plenty of margin. However, if servos or other power consuming devices are being driven by the same power source you must consider the power requirements for those devices as well and provide plenty of margin to prevent disastrous "brown-outs". For instance, a single digital servo can easily draw 1-5 amps depending on it's size and performance. (Note: ESCs do not consume power from the APM) If you experience spurious resets or other odd behavior it is most likely due to noisy or insufficient power to the APM. As with all logic boards, electrical noise from the motors, servos, or other high current devices on the power source can cause unpredictable behavior. It is recommend that a power filter such as this or this be used in such conditions.

Too short or long power wires, bad or old connectors, or insufficient current capability of the APM power source can result in a "brown-out" situation resulting in unpredictable operation. This is particularly true in traditional helicopters where the collective servos can draw 3-20 amps in short bursts. The power source must be able to accommodate this without voltage droop or voltage spikes. A quality switching type BEC such as one of these or one of these can be a solution depending on overall current requirements. Many of these type of regulators are programmable so remember to program them with in the safe operating range of the APM2. Linear voltage regulators are not recommended as they are inefficient and prone to overheating and heat induced failures. APM2 should never be connected directly to a battery of any type.

Power source problems are common and can be insidious and frustrating. Be meticulous. Any autopilot or flight controller is useless and potentially dangerous without good clean power source.

The picture below is of APM 2; but the concept is applicable to APM 2.5.

Comment by marijnsl...@gmail.com, Jan 9, 2013

I believe this documentation might be a bit misleading. I was faced with the following case for a fixed wing plane:

  • 1. The APM is powered on the input PWM.
  • 2. Multiple servos are connected to the output PWM on the APM.
  • 3. Servos powered by a UBEC on the output PWM.

A dual supply setup was chosen because the servos draw so much current that the UBEC cannot hold a steady 5v. At high servo load the UBEC does dip below 4v for very short periods of time, before recovering. Clearly, this UBEC is not suited to power the APM in a single supply setup, it might experience brown-outs. As I understand, the dual supply setup was designed specifically to overcome this problem.

However, the design listed above does not meet the required as specified in this documentation. The following requirement is not met: Power on Output PWM connector 5.00V +-0.5 6V MAX JP1 open

To comply with this requirement, I've been struggling for a while trying to figure out how to get a good stable 4.5-5.5v on the output rail. The solution I came up with was to create a servo power board that powered the servos from the UBEC. Then I'd connect only the signal and ground wires from the servos to the APM. This way I could leave JP1 in, without the servos being powered from the APM power supply. Basically implementing a dual supply system outside the APM.

But I realised this was stupid, the APM already has support for a dual supply system, there should be no need to implement it externally. So I checked the schematic of the APM2.5, and as it turns out, if JP1 is open, the output PWM power is not connected to anything at all. I can only conclude that the APM requiring a 4.5-5.5 volt power supply on the output PWM when JP1 is removed is a bogus requirement.

Thinking back on the whole process I understand why the requirement is there. Removing the requirement might actually make the power setup more confusing for the average user. But I do want to add here: The APM does not require a stable 4.5-5.5 power supply on the output PWM when JP1 is removed. Only the devices connected to the output PWM require the power.

But do note that other requirements are still in effect. Applying more than 6v to the output PWM can still cause damage, also large amounts of noise might still mess with the delicate parts of the APM, even without a direct connection.

I hope this prevents others like me from being sent on a wild goose power chase. :)

Edit: Using Wiki Syntax

Comment by alex.ult...@gmail.com, Jan 15, 2013

In the "single supply", the power can be supplied from either output or input, with the JP1 connected. What if both side has 5v power in this scenario? The board will get power from which side? Or it will burn the board?

Comment by marijnsl...@gmail.com, Jan 15, 2013

Connecting power toboth the input and output PWM with JP1 in place will have unpredictable results, depending on the power supplies used. What happens is this:

The output PWM supply will feed through a diode, lowering the voltage by about 0.3, into the input PWM, this is what JP1 does. This means the output PWM supply will start powering the output of the input PWM supply. (So current can flow from the output supply into the input supply)

Some power supplies do not react kindly to having power applied to their outputs, so you could get bad oscillation which will lead to malfunction. It is unlikely this will damage the board but it's not a setup you want to fly with. JP1 is designed to route power from the output PWM to the input PWM, if the input does not have a power supply. It should not be used to implement a redundant power setup.

Comment by alan.pow...@googlemail.com, Jan 23, 2013

One solution I have in mind is to power the APM2.5 from the power module and every thing else from an sBEC. Using just signal and ground from the RC receiver on the input side and the same to the servos on the output side. Obviously receiver and servo power is from a separate sBEC. This would be achieved using a wiring harness that isolates the two supplies - APM and RC. The one thing that is unclear is, with the jumper connected, is the whole APM powered?

Comment by project member analogue...@gmail.com, Jan 23, 2013

Alex: That won't burn the board, but as marign says it can be suboptimal and lead to unpredictable results.

Comment by project member analogue...@gmail.com, Jan 23, 2013

Marijn: thanks for the feedback. Can you suggest some changes to this page that would help? It's in the technical appendix, so we don't expect regular users to see it, but I agree that it should not be confusing.

Comment by bpd...@gmail.com, Jan 23, 2013

On the apm 2.5 with power module installed. I removed the jp1 pin. With the JP1 pin removed, there is no power output on either input nor output rails because the power module is only meant to power the apm board.

So, I connected a switching bec directly to my Rc receiver which gave me power to my input rails. Then, since I'm running only 2 servos for my elevons on the output rails, I connected my esc which will supply enough power and current to run my set. I have a bec pro that has dual power out lines so I might use one to power the input rail and output rails. At this point, I would remove the red wire from my esc and only connect the signal and ground.

Comment by martynbr...@gmail.com, Jan 27, 2013

Is there a way of rigging the Power Module up to an APM2.0? I know there's no PM port, but could it be wired discretely to the relevant pins on the v2.0 board?

Comment by marijnsl...@gmail.com, Jan 27, 2013

One solution I have in mind is to power the APM2.5 from the power module and every thing else from an sBEC. Using just signal and ground from the RC receiver on the input side and the same to the servos on the output side. Obviously receiver and servo power is from a separate sBEC. This would be achieved using a wiring harness that isolates the two supplies - APM and RC.

The power module is very capable of supplying your RC gear with all the power it needs, however, in that setup, if the RC unit were to short out the APM would fail. If the receiver is powered externally, it would stay functioning.

Breaking out the servo power to an external wiring harness is probably not required though. With JP1 removed the APM does not use the power applied to the output PWM at all. You can use those pins already supplied on the APM to distribute power to the servos. Unless it's a particularly big model of which the servo current might damage the board.

The one thing that is unclear is, with the jumper connected, is the whole APM powered?

The APM only has one single power supply. it is impossible for the APM to be 'half-powered'. In the dual power supply setup the APM is powered by 1 supply and the servos are powered by another. In the single power supply setup the APM and the servos are powered by the same power supply.

On the apm 2.5 with power module installed. I removed the jp1 pin. With the JP1 pin removed, there is no power output on either input nor output rails because the power module is only meant to power the apm board.

Untrue, the power module is ment to power both apm and rc electronics on the input PWM. So the power module will supply power to the input PWM. (If you leave JP1 in it will also supply power to the output PWM, this is a bad thing for most users, so when using the power module, pull JP1)

Is there a way of rigging the Power Module up to an APM2.0? I know there's no PM port, but could it be wired discretely to the relevant pins on the v2.0 board?

I believe so, power is easy. take the red wire, and the black wire next to it. Those are both +5.3v. Connect them together and wire those up to the APM 2. Preferably to the output PWM with JP1 connected. But make sure no other devices are drawing power from the outputs in that case! The two black wires furthest away from the red wire are the two grounds.

The remaining two wires are analog signals for current and voltage. The one closest to the red wire is current. The remaining one is voltage. They are analog signals, and will probably work when connected to A1 and A2 on the APM 2. Be sure to double check everything I said with a multimeter before you blow up your board cause I made a mistake xD

Can you suggest some changes to this page that would help?

I'll see what I can do.

Comment by thinqe...@gmail.com, Feb 8, 2013

I'm still a little confused... Could someone please explain how the above information would impact on my setup:

I have an APM2.5 board running in a (non-3DR) quadcopter. The 4 control leads from the ESCs are plugged into the output headers on the APM, which currently provide power to the board (paralleled I believe). JP1 is connected. The signal lines and power lines from my Rx are plugged into the input headers on the APM, which provides power to the Rx.

I have recently purchased the Power Module. When I plug this into the APM, do I need to remove JP1? Does this mean that the board is powered by the BECs in the ESCs or the line from the Power Module, or both? Do I need to remove the +5v pins from ESCs so there's only one power source (the Power Module) to the APM, or if JP1 is removed, does this not matter?

If I then want to use the APM in a plane, which only has one ESC, how do I provide power to the servos? If they're all plugged into the output headers and JP1 is removed, am I right in thinking that the APM is powered by the Power Module but the servos are then powered by the BEC on the ESC?

Hope my questions make sense!

Many thanks,

Ben

Comment by project member cr...@3drobotics.com, Feb 8, 2013

>>> The 4 control leads from the ESCs are plugged into the output headers on the APM, which currently provide power to the board (paralleled I believe). This is not where the power come from. These are the signals from the APM to the ESCs. >>> I have recently purchased the Power Module. When I plug this into the APM, do I need to remove JP1? Yes. >>> Does this mean that the board is powered by the BECs in the ESCs or the line from the Power Module, or both? If you have the Power Module plugged in and JP1 removed, it is powered by the module. >>> Do I need to remove the +5v pins from ESCs so there's only one power source (the Power Module) to the APM, or if JP1 is removed, does this not matter? No, just remove JP1. >>> If they're all plugged into the output headers and JP1 is removed, am I right in thinking that the APM is powered by the Power Module but the servos are then powered by the BEC on the ESC? Yes.

Comment by stevetor...@gmail.com, Feb 10, 2013

I'm using a BEC and have disconnected the + wire from all ESCs. Is there any reason to choose to power 5.37 from output rail versus 5v on input rail? I'm using castle BEC so can set the voltage but wanted to know if there was any advantage to using the input vs the output rail in a single power setup.

Comment by h...@vandooren.cc, Feb 23, 2013

I just bougt the APM 2.5 with power module and want to use it for my TREX 450. Through the power module or the USB the inputes are powered. According to the instruction I connect the ESC directly to port 7 of the receiver. There is no power on the output headers. So I assume the comment above "Untrue, the power module is ment to power both apm and rc electronics on the input PWM. So the power module will supply power to the input PWM. (If you leave JP1 in it will also supply power to the output PWM, this is a bad thing for most users, so when using the power module, pull JP1)" is correct Then why should I not use JP1?

Comment by jpbarnet...@gmail.com, Mar 1, 2013

Hi guys, I've been doing a lot of reading on the power subject - a lottttt of reading, and naturally there are a lot of different opinions. I've decided that I want to power my APM directly from the PDB, not from the APM power module Without a thousand acronyms and attempts at explaining, here's a photo mock up of my set up. Ignore the 6 coloured wired poking through the centre of the PDB - 3DR was supposed to send a 4 pin socket :-/

<img src="http://www.dropbox.com/s/fxdtm58soocl1ke/20130301_224802.jpg" />

From what I can gather, with this set up, the voltage supply to the APM2.5 will essentially "sort itself out" - and with this configuration i shouldn't have to cut or connect any jumpers. That's my impression, i'd be really interested to hear yours. Cheers, James.

Comment by jpbarnet...@gmail.com, Mar 1, 2013

http://imgur.com/JzyWqA8

Hi guys, I've been doing a lot of reading on the power subject - a lottttt of reading, and naturally there are a lot of different opinions. I've decided that I want to power my APM directly from the PDB, not from the APM power module Without a thousand acronyms and attempts at explaining, here's a photo mock up of my set up. Ignore the 6 coloured wired poking through the centre of the PDB - 3DR was supposed to send a 4 pin socket :-/

<img src="http://imgur.com/JzyWqA8 />

From what I can gather, with this set up, the voltage supply to the APM2.5 will essentially "sort itself out" - and with this configuration i shouldn't have to cut or connect any jumpers. That's my impression, i'd be really interested to hear yours. Cheers, James.

Comment by project member billbon...@gmail.com, Mar 29, 2013

@jpbarnett84 You need to disconnect one of the power sources. Either use the APM PM with JP1 removed OR if you still want to use the APM PM as current and voltage sense, you need to disconnect line 1 (red) and line (2) black and next to the red one from the PM.

Otherwise you will have two voltage sources as different voltages. The voltage will raise to the higher one, and current will flow. This current will be dissipated as heat in the circuit. Which may or may not cause a failure.

If you power from an ESC, make sure it output 5.3V-5.5V. There's a protective diode/500mA fuse that drops the voltage to Vcc to 4.8V to 5.0V due to there forward resistance. With only 5.0V you get 4.5V for Vcc and that 's right at the bottom end of a good working voltage.

Comment by robert.d...@gmail.com, Apr 9, 2013

Hi

My hexacopter will fly with 6S Lipo but the 3DR Power Module has a max input voltage of 18V, that means it works fine with max. 4S Lipo. Do you have any idea how i could power the APM 2.5 board? Can i use the ESC-BEC from one of the 6 BEC's? regards, Robert

Comment by project member billbon...@gmail.com, Apr 9, 2013

@robert: You can power your board using the ESCs internal BEC. Just connect JP1 on your APM2.5 and make sure if you are using ArduCopter? you have the 5V/GND wire coming from the PDB

Comment by frank.sl...@googlemail.com, Apr 15, 2013

Isn't it like that:

Please correct me if the scheme is wrong.

Comment by project member billbon...@gmail.com, Apr 16, 2013

@frank. The diagram is misleading. You are saying that you will fry a APM when JP1 is on with power module and usb. It will not fry the APM. With JP1 closed and an ESC connected and Power module on will also not necessarily fry the APM (The ESC may not like it). One user reported an hotter ESC due to the extra current draw from the voltages trying to match, but the APM in this case is protected by diode/fuse. With JP1 Open, PM, USB & ESC is the exact configuration used for Arduplane. Maybe you could move the diagram to http://www.diydrones.com/forums for a better discussion that can be had here.

Comment by frank.sl...@googlemail.com, Apr 17, 2013

Hi Bill thanks for your reply. I would like to sort this out here if you don't mind.

In the famous youtube video http://youtu.be/TFCmUuvcH04 it is emphasised that you should not connect the JP1 jumper while powering with PM. And the explanation seems logic to me.

What I learned from you is that also three power supplies (PM, USB & ESC) at the same time do not harm the APM. Can you tell me what happens with the power supplied via USB?

What are the combinations that can destroy the APM? My diagram would be like that:

Comment by project member billbon...@gmail.com, Apr 17, 2013

@frank: to put it simply, don't connect JP1 if you have the power module connected. Options 4 and 5 are not valid. If you do you probably get a hot ESC. Connecting USB makes no difference. In the video you posted he states the same, do not use JP1 with the power module.

Heat is not good, it drains the battery faster and reduces the lifetime of the components.

Comment by ronny.gr...@gmail.com, Apr 23, 2013

Hi! Finishing my X-8 Drone and do not want to mess up now... I´m going to to connect a 5V low noise UBEC on the input rail to power receiver and electronics. (Not using power module due to 6S Setup with AttoPilot? sensor) JP1 open Then want to connect a 6V SBEC to the output rail to power HV servos and retracts. The retracts do not work well at 5V Is there a risk to damage the board with 6V on the output rail with JP1 open? Or should i make a separate power wiring to power the gear?

Comment by ronny.gr...@gmail.com, Apr 24, 2013

No answer so i made a separate feed to the gear with 6V... Maiden tomorrow

Comment by stevetor...@gmail.com, May 27, 2013

I have an octo and am using a castle 10A BEC as I can't use the PM because my amps are too high. Does it make a difference if I power via the input or output rail like it shows at the top of this page. Power on Output PWM connector 5.37V +-0.5 Power on Input PWM connector 5.00V +-0.25

I'm not using any servos and my Rx is connected to the input rail.

Is it better to connect the BEC to the input or output or does it matter?

Comment by project member billbon...@gmail.com, May 28, 2013

@steve: If you connect via the outputs there is a diode and a fuse that protect the APM from excess current and over-voltage. but they drop the voltage by 0.37 to 0.5V so I would recommend at least 5.5V on the Outputs Rail. If you connect to the Inputs you need 5.0V exactly for best results, but you bypass the protection.

Comment by stevetor...@gmail.com, May 28, 2013

Thanks billion…! That's exactly what I was expecting. I will power it via the outputs and set the castle to 5.5V.

Comment by thext...@gmail.com, Feb 18, 2014

It looks like this page was edited? (May 27, 2013) So I can follow the right instruction here.

Comment by adriancj...@yahoo.com, Jul 5, 2014

Anyone using a 3dr power module, have you tested the two 5v pins out? I was testing mine before installing to make sure all inputs were right (they always get the wiring wrong when you by knockoffs). I'm getting a reading that varies from 7.11v to 7.14 v. Do I have a bad module, or do I need to read it differently? I used both pos pins and both gnd pins, same readings. I saw where it says do not apply more than 6v to the apm or the magic smoke comes out.

Comment by adriancj...@yahoo.com, Jul 5, 2014

A follow up question, what if I just clipped the 2 pos Vcc wires and power Apm through esc. Would I still be able to monitor voltage and current, or does the Vcc need to be active for that to work?


Sign in to add a comment
Powered by Google Project Hosting