Fix pixel voltage drop with multi-wire cable -- which wires to "double up"?

[johnty]

I've got strings of 100 pixel 12v 2801s, each attached to a SD E682 with a 10' extension cable from Ray Wu. All is good. This year I needed to add another 10' extension to each string and now, at 20', the pixels flicker when more than about 70 are set to white. Measured voltage drop is about 2v. I appears that the extension cables are 24 gauge which has too much resistance for a 20' run.

I'm going to buy some 18/4 wire and make my own extensions. The Question:

I need three wires for +V, data and ground. Which one would benefit the most from the fourth wire in parallel? The +V or ground (I assume data is very low current). Or does it make any difference. I could wire up a connector both ways to test but thought somebody might have some insight to this issue.

Thanks,
John

 

[David_AVD]

If you have the choice of only beefing up only one conductor, make it the 0V / V- / ground one.

 

[johnty]

Great. Thank you.