Proper Grounding

[Endevor]

Long term help: Does anyone know any good links or articles to show how to find out how to properly ground something to the arduino?

Short term issue:
I'm having some trouble with grounding my circuit to a Arduino Mega. My goal is to reduce the load as much as possible on the onboard step down (Which I know is primarily from the power input), I was kind of curious on if the ground returning to the arduino has an effect on that.

I'm using an Arduino Mega
I'm using 8 Meanwell LDD-100h drivers to run 8 LED Channels in parallel.
http://www.ledgroupbuy.com/meanwell-ldd-1000h-led-driver/
I have a 12v 8a power supply for the LEDs.

Each channel has three LEDs in series.
The LDD Drivers are run by PWM signals from the Arduino
Now, when looking up proper circuitry for wiring this all together, I was informed I needed to ground the drivers to the Arduino board... It worked, but now I'm having some issues with the board not being able to handle a whole lot...
I'm a little concerned (And I'm no expert on this) since the Arduino typically runs with 5v signals, why I'm grounding a 12v line to it. (The positive line from the PSU runs through the drivers -> LEDs, then returns to the ground line back to the PSU and the Arduino) Do I need to have a resistor between my circuit and the Arduino GND? Am I wiring something wrong?

Thanks in advance for any help.

[CrossRoads]

Connect all the grounds back at the power supply instead of depending on the ground wire from the arduino to the supply.

[Robin2]

There needs to be a common ground so that everything has a common point of reference. Connecting together the grounds from different voltage systems is normal. There would only be a problem if you connect the 12v end to one of the Arduino pins.

If you have a separate power supply for the LEDs there should be little or no current passing through the ground connection so nothing special is required beyond being sure the connection won't come loose. It's not serious like the grounding for safety in a mains voltage system.

Post a diagram of your wiring system and we can give better advice.

...R

[Endevor]

I attached a rough sketch of my wiring...
The LDD wiring may be confusing, but just know they're in parallel from the PSU and return to a single ground as displayed.

[TomGeorge]

Hi, I agree with Crossroads, make the power supply negative as your reference ground.
So that when you have a piece of equipment that needs a ground you use that neg terminal, the arduino ground is also connected to this negative terminal, that way all currents flowing flow back to the powersupply, but not through the arduino.

Tom....