Power injection addting an additional pigtail to an existing 2 core cable with pigtails

[janastas]

Hi All,

I'm currently running all my power injection straight from a power distro board to a particular point to power inject.

What I'm currently doing is at the end of the pixel string I'm adding a power tee that allows you to plug in a 2 core ray wu pigtail to provide power, the tee can be found via the following link (https://www.aliexpress.com/item/1005002060475726.html?spm=2114.12010615.8148356.9.71ba64e81htt9P)

What I'd like to do for the two core cable coming from the power distro board and at the first injection point cut in and add a second pigtail to continue the power injection run so I don't have to use another terminal from the power distro board.

I don't expect to power inject more than 2-3 times on each of my pixel controller ports but was wondering if any forum members can provide some examples but also how you'd water proof the additional 2 core pigtail coming off the main one

Example of what I'd like to do below.

Pixel controller and pixels setup.png

• janastas
• Mar 11, 2021

 

[i13]

One way to simplify this would be to power the positive in both directions at the injection points; you could halve the required number of injection points without any of the pixels being more than 50 away from an injection point.

It is possible to splice and join cables. I've done it by soldering the cables together, putting heatshrink over the join and filling it with silicone glue before shrinking. If I branch thin cables off of a very thick cable (e.g. branching 18 AWG from 8 AWG), I cut into the side of the insulation of the thicker cable and branch off of that. I don't cut through the thicker cable. Note that some heatshrink shrinks to a quarter of its original diameter but some only shrinks to half.

 

[janastas]

Ok thanks, I have some tees on the way that power both ways so will use those and see how I go but deinfately will try the silicon glue and heat shrink. Would any old silicon glue from bunnings do the trick or do I have to buy something specific?

 

[i13]

I'm not sure how much it matters for cables but I've always used neutral cure silicone. It is supposed to be the best type to use for strip lighting which I also have. My understanding is that it doesn't cause corrosion. Bunings sells it along with other types.

Cheaper silicone is generally lower quality. It can discolour in the sunlight. I've had one tube that I opened and sealed up again for 18 months. When I went to use it again, it literally took a year for it to set. Lesson: check that the silicone glue sets before putting the tube of silicone to use, especially if it is a cheap tube of silicone that has been open for a long time.

 

[TerryK]

If the cable from the power distribution board is heavy enough I would splice in another connector; creating a 'Y' at the very end of the cable. As i13 has mentioned, solder and heatshrink. I typically try to use a type with an internal adhesive, Marine grade as I recall. Somewhat beside the point but I currently use White, Red, and Black to help color code the connections.

As I do not yet have anything that remains outside year round, I'm not to concerned about moisture seepage as everything is stored inside and any seepage should bake back out during the hotter off season months.

With the 400 pixels I would think you are getting close to maxing out the distribution terminal and depending upon distances from the power supply to the various string segments, voltage drop. Something to note, every connector will introduce a small amount of voltage drop as will whatever wire size is used in the TEEs. With this in mind, rather than splicing in another pigtail, you may consider running another power injection cable from the distribution terminal. It would not help with maxing out the board but may help with voltage drop.