There seems to be a big, big issue with builders frying the APM 2.0.
A good many of them seem to know what they are doing. What is the problem?
I want to know once and for all how NOT to fry the APM 2.0.
It's my understanding that the APM 2.0 needs/uses 5v. It is also my understanding from the posts and submissions from the forums that supplying more or less than the stated 5v can or will cause issues.
Seems simple enough, but then why are guys having a problem?
I'm not a computer scientist or electrical engineer, so I must rely on the kind help and support from others here.
In my case I have a servo that must use 6v because of the torque. My Castle Creations phoenix Ice 50 motor controller is programmable and can supply 5v.
I also have a separate Castle Creations BEC battery eliminator. It is also programmable and can supply 4.8v-9.0v
Now, beyond the 6v servo. I am not running anything special. I plan on using the GPS, xbee and maybe the wind speed sensor.
The question is using a single 4s 5000mah lipo, what is the safe and correct way to wire the APM 2.0 so as to NOT fly it?
Set everything to 5v and see if you really have a problem running the servo at 5v.
Unfortunately the servo stalls. So yea that presents the problem.
Do I need to be concerned about something regarding grounds being supplied from different voltages? Somebody said that might be an issue. For some reason I'm having serious brain fade on how to separate these two power sources.
Check my logic on these connections.
1. The Castle Creations Phoenix Ice 50 motor controller set at 6v would supply the APM output because the APMs throttle ch connects to motor controller.
2. The Castle Creations BEC battery eliminator set to 5v would connect to an unused R/X ch thus powering the APM's input side at 5v.
Still doesn't seem right
You could power APM with a simple 5V BEC and a smaller battery, and then power your RC gear(servos, motors) with a separate power supply entirely at the desired voltage, and then just send the signal lines to APM output rail.
They will need to have common ground.
Hi John, I am quite into electronics as a hobby, and I had a sililar problem using a 5v servo running straight from the receiver that was powered from the apm2, whenever I moved the servo too much juice was sucked from the apm2 and it shut down causing my Tricopter to crash. Whilst it seems fine to power one servo from the output rail. Now you can have a common earth with any voltage going to the apm just dont connected the positive also if more than 5v. What I tend to do is run off the main battery using a ubec to power the apm and esc`s all of my esc`s have the positive wire from the plug disconnected as they are linear bec`s and not very effiecient. ow if you need an extra voltage supply that is higher than 5v simply add another ubec and set it to 6v it wont have to supply a great amount of amps so it need not be big in size and connect the positive and negative wires to the servo and the signal wire (usually white or orange) to the apm or receiver depending on your requirement. Please ask if I haven`t explained it clearly?
Yes, we are talking about the same thing. I usually just use a proper 5V BEC with enough juice to power everything to keep the wiring simple. But there has been some instances of people running servos on a separate battery and only connecting the servo signal wire to the APM without using common ground. This is a big no no. :)
One battery or two in this case it seems like it really shouldn't matter if I am using the the Castle Creations BEC battery eliminator right?
So are you saying that I use just the signal pins on the APMs output side, so that just the throttle signal wire is going back to my motor controller? For the servos I would use APMs output rail and again use just signal wire going to the servos but then splice the power and ground from the motor controller?
What would be the best way to attach the 5V BEC? Connect it directly to the apm on an unused ch. or connect it to the R/X on an unused ch?
will the final setup be grounded correctly?
Thanks for the input.
There are other ways of doing things but for example, the way I have my Tricopter wired up is as follows. I have one 3amp 5v ubec powering the apm via the output rail which then supplys the receiver and a small servo also on the output rail, the esc`s are also connected to the output rail but I have removed the red lead as if this is connected it will use the bec from the esc to power the output rail also, which I would rather not only for the reason that they are inefficient and the energy wasted is turned into heat, which in turn heats up the esc twice as much as it gets without the bec connected, but everything else on the output rail has all 3 wires, I also wanted to add another separate servo (but could be anything 5v) which I cant connect directly to the apm as it would take too much power from the apm, so I have just the signal wire going to the apm and a y-lead on the ubec firstly supplying my apm and secondly supplying the red and black to the servo.
Now if you wanted another voltage higher than 5v, the best way in my opinion that would be to use another ubec that outputs a higher voltage, and again there are other ways that dont use a ubec but I feel this is the best way?. So with the other ubec connect it directly to your power distribution board or mains battery and the red and black wires to the 6v 10v or whatever device and the signal wire to the apm or receiver. The signal wire is used for communication via pwm. The grounds are all common as they come from the same supply.
Using a separate battery is not worth the weight gain.
--I WOULD URGE ANYONE NOT ENTIRELY SURE ON HOW TO DO SO, NOT TO ADD ANYTHING HIGHER THAN 5V TO YOUR APM--
What John AB,
Is saying is also a valid point, if you do use a separate battery you wil need to connect the earth from that to your main battery or another earth in the circuit irrespective of voltage. The positive can be isolated to what you need it for?. But again if this is done wrong it will cause problems.
Unless the voltage required is substantially different from your main battery I would suggest not using a separate battery..