MultiWii

https://youtu.be/I5uDzraRaXc

Hi there,

I proudly set the fpv system on my drone and it is working pretty well, except that the right bottom motor does not spin anymore. I know the two things should not be connected, but maybe they are because of how I "gave power" to the fpv tx and camera.

First of all, all the ecs and motors are powered through the pdb board. I did not know how to give power to the fpv system , so I soldered a jst connector to the same "pdb connectors" that gives power to the right bottom motor as you can see in the image attached.



then the jst gives power to the fpv system... the result is that the fpv system works but the motor does not spin. I also tryed to unplug the fpv system, but the motor still does not spin. This makes me think that maybe the problem is that I just didnt re-solder the ecs very well? I just wanted to ask your opinion before I resolder everything. Maybe the way I give power to the fpv system is not right? If so, what would you suggest?

It looks like you have the red wire soldered on a pad that says signal. The photo gives no clue which wire is which or where exactly they connect to the power distribution board. You don't want to try and get your 5v or whatever from your signal pad (just in case that is really what I'm seeing, I can't really tell.) The fact that I see a red and black connected to two black wires is beyond me.
A couple of suggestions. Undo whatever you did to create the motor not spinning problem. If your FPV uses straight li po voltage, take a parallel off the cable that plugs into the battery. If it takes 5 v, use one of the (hopefully) unused remaining 3 ESCs BEC 5v supply. You should be powering your FC off of one of your ESCs, use one of the remaining 3 to run your FPV. If it takes some other voltage like 6 or 7 or whatever, they sell UBECs in varying voltages and amperages to supply almost anything you can think of. To power a UBEC you parallel connect to the battery connector.
If you are trying to get straight li po power to the FPV system you would normally tap in to the PDB "battery in" circuit and not on the "ESC out" side (if that is how you have it.)

Hi,

sorry the image is not clear. the signal text is referring to another pad. I can ensure I'm not attached to it. You see two black cables just because I covered both of them with something black, but there is is a red and a black wire.

I will try to follow your advices! I WILL put it in the battery in! u are right, do not know why I didn't think abt it!

thank you!

My guess is that when the FPV is hooked up and turned on, it acts as a dead short on the ESC buy allowing current to go from positive to negative though an alternative path (the FPV) other than the intended one through the ESC circuitry. ( but that's probably wrong too.)

So thisnisnwhat Inhave done until now:

1) desolder the jst connector for the fpv system
2) detach the fpv system completly
3) try to plug again the battery and test the motors

Same problem with the motor not spinning

4) I tried to change the esc with a spare/nee one. Same problem: the motor does not spin (it just does that syrange movement that you saw in the video)

Now that the fpv is detached and the esc is changed, the only thing I can say at the moment is that maybe the motor is damaged? Could it make sense? In this case, I have to order a new motor...

Or something is wrong with your FC (hopefully not.)

To see if it's the controller..
Connect the esc direct to the Rx and test if it works then.

Kbev5709 wrote:Or something is wrong with your FC (hopefully not.)

ah... To verify that, can't I just try to hook another working esc+motor in place of the non-working esc+motor and see if it spins?

PatrikE wrote:To see if it's the controller..
Connect the esc direct to the Rx and test if it works then.

Hi Patrik. I'm not sure I understood how to do that. How can I connect the esc directly to my radio controller? (sorry for the noob question, but I'm really new to all this )

paco76 wrote:

Kbev5709 wrote:Or something is wrong with your FC (hopefully not.)

ah... To verify that, can't I just try to hook another working esc+motor in place of the non-working esc+motor and see if it spins?

yeah, that would be a good way to check that.

Ok I swapped D3 (on which there were the working esc and motor) with D9 (to which the new esc and motor were attached). the motor that was on D3 spins correctly. the motor that was on D9 is still not spinning, confirming (I guess) that the motor has a problem. Just to be sure I want to desolder and solder the ecs to the motor once again because I always have difficulties to solder the motor to the ecs and I'm not 100% Sure I did a good work (don't know why, but the cables of the motor are always difficult to solder... the skip all the time)

Fixed!

I didn't solder very well the motor to the esc...