One of the top things I see people confused about is power injection. Here’s the “how” behind it, and a few different ways to get it done!
In the hobby of Christmas lighting there is one subject that is really controversial as far as there being many many opinions on how to do it; that is power injection. So let’s discuss with nothing but the facts. What is power injection in the first place and why would we need it?
What Is Power Injection?
When we’re running Christmas light pixels we run them at 12 volt or 5 volt. As electricity goes through wires over distance, voltage starts to drop. This will happen more quickly with thinner wires than thicker wires, but it happens in every piece of wire. When working in the US with typical household power, it is at 115 volts on average. When electricity travels across an average wire and drops 5 volts it usually is not a problem and everything will still be able to operate; however when you are running 12 volts along the distance of the wire, you are now operating at only a tenth of the original capacity. This inability to provide enough voltage to your pixels will cause things to stop working, and this is why adding power injection is useful.
Chief Causes Of Voltage Getting Too Low
The main reasons that you would find your voltage getting too low is if you are looking to add more pixels off of the same port, but the power has dropped too low, or you are aiming to have extra length of wire between pixels to the point where the voltage drop over the wire adds up too much to function properly.
How To Solve
If your voltage drop exceeds the amount you need to run your lighting properly, the solution doesn’t always have to be but can be injecting more power.
The first two things you need to start with your power injection are a power supply and a power distro board.
How Does Power Injection Work?
Power injection works one of two ways. The first thing you need to decide is if you are coming from the same power supply or a different power supply.
Same Power Supply
If you’re in a situation where you are close to the controller but you just have a large amount of pixels then often times your power injection can be from the same power supply.
The benefit of connecting at the same power supply is that you can double your distance and just add power at the end of your run of pixels. The key is that at the very end of all of your pixels to build a piece of custom wiring that is not much more than 25ft away in distance, and wire in the voltage plus and voltage negative from your same power supply that is powering your pixels through the controller. This will allow the power to carry through the entire way.
Different Power Supply
If you are not going to be using the same power supply you would use your power injection board, hook your power supply into the input terminals, and hook the pixels to the output side. The biggest key here is that at the midpoint, wherever you need to add more power, you want to cut the voltage positive. That is the most important part.
Power Injection T’s
There are a lot of vendors who sell power injection Ts, which are essentially T shaped connectors which allow you to connect all three wires through. With a power injection T you simply go one pixel string through to the other. This is where right before that T you will want to cut the voltage positive.
From the bottom, you will then cut the data, or not have any data connected and you are good to go. That will mean that between all three connections, the negative is connected.
At the end of the day the reality is that power injection really isn’t necessary for most people. It depends on your personal needs of what you are trying to accomplish but more often than not, it’s almost better to use more smart receivers or just to use less pixels per port. With as inexpensive as the newer controllers are getting, it can just make your life a lot easier to keep things simple.