Slip ring wiring.

[Moogie]

Someone more used to wiring tank mfu's might be able to answer this question for me.
When wiring servos, leds through a slip ring is it ok to join all the earths together, i cant think why it wouldn't but i don't have any experience with the Heng long mfu. Its a Mato 18 wire slip ring from Forge Bear if that makes any difference.
Any help would be greatly appreciated.

[john1970]

Not for LEDs as the heng long mfu switches them on/off though the earth as for servos I don't know much about them so someone else will need to answer that

[Jib]

I generally don’t combine grounds to keep everything straight whejnI’m looking at it, but I know with Taigen/Torro tanks, they have a common ground for turret elevation and the recoil/airsoft motor.

However, they do have separate wire pairs for the machine gun LED and muzzle flash, so yeah, I guess they keep LED type stuff separate.

[Moogie]

Thanks lads, just didn't want to take a chance and blow up the board.

[Jib]

So looking at some PDFs it was partially off on my statement.

Taigen/Torro use a common positive wire for the elevation and shot trigger motors, but they each have their own separate ground. This is what goes through the slip ring

They also use a common positive wire for the hull machine gun and front headlight LEDS, and each of them have their own ground.

Again though they are keeping motors and LEDS on separate circuits. Gun muzzle flash is also on its own circuit.

[tankme]

The common grounds for LEDs affects the HL MFUs older than the 5.3, the Clark boards, and Taigen/Torro MFUs. The newer 6.x/7.x Heng Long boards use seperate grounds for each LED. For that reason, I'm not sure if they are switching LEDs on/off using the ground or the voltage side. I guess if you wired the LEDs with a common ground and they all turn off/on when any of them are triggered then I guess you know that they are using the ground to toggle them. If it's on the voltage side then a common ground shouldn't be an issue. I suppose if you used an ohm meter between the ground pins of say LED1 and LED2, with one LED off and one on you would see if there is an electrical connection between the grounds. If both LEDs are on there should be 0 ohms on the meter if they share a common ground. If the meter shows the connection "open" with one LED on and one LED off, then the ground would not be common. It would also indicate they are switching the LEDs off/on using the ground and not the positive side.

At least that makes sense in my head...

[Moogie]

Thanks for the information.