Hi All, I have a run of 722 pixels (5v ws2811). They are basically continuous, except about 20’ from controller to Pixel 0, and a 12’ jumper between pixel 201 and 202. Total distance is about 200’. I have parallel power via 18awg wire, that injects every 50 pixels. When running the RGB pixels in their purest white, I’m getting a lot of color loss the last 60’ or so. The white turns very yellow/orange. Not very noticeable with other colors.
I’m thinking about using some 12awg wire (with fuse) and bringing in a new parallel injection line straight from the PSU and tapping it in around the area where the color noticeably drops.
1 - Do you think the larger 12awg will help?
2 - Any issue with just using 12awg speaker wire for that new injection line?
Your total run of 722 LEDs could be drawing 30A+ at maximum.
If you just run a single piece of 18AWG parallel to the strip, it will still be trying to supply at least half that (and probably more) over its length.
If you run one of the voltage drop calculators on a piece of 18AWG over 200’ carrying even 10A of current, you’ll see the drop is very large on your injection wire. The 12AWG will be better, but you definitely want multiple injection runs from the main supply, not just 1 or 2 wires. If you want to do real injection every 50 pixels, you’d need 14 injection lines running back to the main supply. Realistically, you probably want to budget for “mid wire” injection points where each wire handles 50 LEDs to the left and to the right of the injection. You need 1/2 the injection wires, but they need to supply twice the current (about 4.25A each line). You can probably get by with 18AWG for the first 3, but the remaining 4 will be where you need the
12AWG.
Put the different lengths and wire sizes in at 4.25A and see what kind of drops you get with the Drop calculators. You might be better off putting in a secondary 5V supply and use that to inject from the far end and back. Much shorter runs that way.
As long as your wire is copper (not copper clad aluminum) you’ll be fine.
Incidentally, these longer setups are why some (me included) like to run a 24V supply and use 24v->5V buck converters at the injection points. You can usually get away with a single bus wire since the high voltage current is much less (22%) than the 5V. Your single 18AWG would likely be fine in that setup, but you probably need 8 (or more) buck converters.