Motion pack A and receiver exits

[Didier Molard]

Hello.
I'm struggling with my motion pack
transmitter is futaba T7c, mixer on right stick for motion and turn
checked with the receiver + servo : whatever the movement, both servo moved, either same direction, either opposite depending on position of the stick.
So mixer is ok, and exits of the receiver too !
power box installed, connected to motion A box, receiver connected with motors connected to exits 1&2 (like servo) , no other boxes connected
so radio on, isolator on, and only one motor is running ?
the mixer is active, as the motor changes its rotation depending on position of the stick.
but what could cause the 2nd motor not to turn??

same model with silver boxes, this transmitter / receiver / set up was working correctly.
Regards

Didier

[Didier Molard]

Hello Some news..

finally found why i had some issues with the motors
seems the connection to the motor terminal needs to be "hard to fit" for everything works. Mine were not loose, but not hard enough for it works well.
so now i have both motors running, and in the right direction.
but when i connect any if the servo plug from the B motion drive (so elevetaion / turret rotation) , i have the elevation / rotation, but none of the drive motors wants to run ?!

Does anyone got same kind of issue ?
wondering :
as both motion boxes are supplying current to receiver, could there be some interaction inhibiting the motion box A to operate in that case ?
i will try to remove the plus wire on the servo plug soon to see if any impact..

Regards
Didier

[Didier Molard]

hello all

Made a test this morning , removing the + pin in the wiring of the servo plugs coming from motion box B on the receiver solved the issue.
Do not know if this is common, or may be due to my red boxes being from early batches.

Regards
Didier

[Gerhard Michel]

Hi Didier,

there must be only one power source in your receiver circuit. Two BECs may cause trouble and even damage to the components.

[Didier Molard]

Hello all.

Hi Didier,

there must be only one power source in your receiver circuit. Two BECs may cause trouble and even damage to the components.

That' s also what i've found/guessed, but seems both A and B motion pack boxes are able to act as a BEC.
and as both are to be used, means mandatory to remove the "+" in the servo plugs comming from one of them
that is something to take care of.
my version of install of red boxes is from Aug 2019, vers 2.0 and do not menytion this, may be this has been updated later on.

Regards
Didier

[Andre Meylan]

Hi Didier,

there must be only one power source in your receiver circuit. Two BECs may cause trouble and even damage to the components.

Very important from Gerhard to mention the power source. BEC's are commonly used in models such as airplanes and helicopters in order to save the weight of additional batteries. Also in cars when you don't have much space. In our large tanks, there is neither of that to think of. That is why for my Leopard, I will not use any BEC's to provide current to the receiver but a separate source with a protected circuit such as from PowerBox Systems
(www.powerbox-systems.com).
So I will be able to power up my RC systems prior to switch on the main batteries for safety reasons.

Best regards, Andre