Pixel Power Injection

[Denny]

I am outlining my house with pixels this year and will need to use power injection and null pixels due to the distances involved from the controller.  I know I need to install null pixels every ten feet or so and also power injection about every fifty pixels.  Do I need to use a separate power line or can I simply tap into the 12 volt power lines in the main line from the controller?  With my pixel trees and grids, I have always run a separate power line from the power supply, but if I can just tap into the line from the controller, it would make wiring a bit simpler.  

[uncledan]

You can use the same PSU that's powering the controller.   If using a different psu don't connect the +, just the - between strings. I fuse all my power injection.  Depending on voltage of pixels and wire size you should be able to go more than 50 pixels.  I routinely go 100 pixels with 2811 12v with no issues.  You would power from both ends of the string.  For example inject at pixel 1 and pixel 200, feeding power from both directions. 

[Denny]

22 minutes ago, uncledan said:

You can use the same PSU that's powering the controller.   If using a different psu don't connect the +, just the - between strings. I fuse all my power injection.  Depending on voltage of pixels and wire size you should be able to go more than 50 pixels.  I routinely go 100 pixels with 2811 12v with no issues.  You would power from both ends of the string.  For example inject at pixel 1 and pixel 200, feeding power from both directions. 

On my matrix and pixel trees with 150 pixel universes, I generally tap in between 100 and 101 with power injection. With the pixel trees and matrix, I have always used a power line separate from the line attached to the controller and controlling the pixels, in other words, two lines for each universe. Rather than doing that, I was curious to see if I could just use the line from the controller and tap into the power strands for the power injection.  Or do I need to run a new line from the power supply to use for injection?

[Vince4xmas]

Can you also inject in-between? Between pixel 75 & 76?

 

[Denny]

13 minutes ago, Vince4xmas said:

Can you also inject in-between? Between pixel 75 & 76?

 

When I first started using pixels, everything I read said to inject power every 50 pixels.  That said, "unclean" said he has no problems for 100 pixels.  So, I don't see any reason that 75 & 76 would not work.  Since everything I have done to date has used 150 pixels per universe, I always injected at 100 and 101 since that provided power to every 50 pixels in the universe.  I would say try 75 and 76 and put them on at full white.  If you don't see any color shift to red and they are all white, you are good to go.

[uncledan]

2 hours ago, Denny said:

On my matrix and pixel trees with 150 pixel universes, I generally tap in between 100 and 101 with power injection. With the pixel trees and matrix, I have always used a power line separate from the line attached to the controller and controlling the pixels, in other words, two lines for each universe. Rather than doing that, I was curious to see if I could just use the line from the controller and tap into the power strands for the power injection.  Or do I need to run a new line from the power supply to use for injection?

Not sure what you mean by "the line from the controller".  I'm assuming you might be talking about the + from the output on the controller?  Injection would come from the PSU that supplies power to the controller.  If injection is coming from another PSU the data and - would continue from strand to strand breaking the + between.  Don't connect the + from two separate psu's on the same string.  Pixels will vary from different manufacturers.  I order all my pixels with 18ga wire and always test before figuring out my power needs. 

[mpageler]

You can inject power between any pixels.   You simple splice in your injected power cord, to the existing (/- wires between pixels. From my research, how many pixels before doing this will depend alot on distance form controller to pixels and wire gauge you use.

As I understand the OP's questiopn, they must have a single output PS? In that case, you could split the output +/-, one to feed the start of the string and the other to inject power midstream.

 

For my 124 pixel wreath, I inject at 50 since I have over 20 feet 20gauge wire between controller/pixels. Used the Sandevices full white test pattern and saw a dimming when injected power was disconnected.

 

The "injected power supply" wiki on the doityourselfchristmas.org site has a nice overview with graphics on how to do it I think they show both 1 and 2 PS setups.

 

 

[EmmienLightFan]

15 hours ago, Denny said:

"unclean"

I think you mean "uncledan".

[Ron Boyd]

The best way to figure out where to inject power is this:

String up however many pixels you have on the element, turn them on 100% intensity, white, where they start to dim or get a reddish or muddy yellow, (kind of like warm white) that's the point where you inject.

Don't worry about how many, just where the hue changes.

You can back inject also. This is how people are getting 100 or so pixels per run. I "t" the power in just like the ground. This way, all pixels get the power they need.

Edit:

To give a good visual reference, watch this: http://blog.holidaycoro.com/2013/05/a-demonstration-of-effects-of-power.html

and read this: http://www.doityourselfchristmas.com/wiki/index.php?title=Power_Injection

Two excellent articles on power injection.

Sent from my SAMSUNG-SM-N910A using Tapatalk

Edited July 27, 2016 by Ron Boyd
add links

[Denny]

5 hours ago, EmmienLightFan said:

I think you mean "uncledan".

Sorry about that uncledan!  Typing on my cell phone during a power outage and 111 degrees.  Guess my mind was a little "cooked."

[uncledan]

Not the first time I've been called "unclean".  No worries "Donny"

[saxon]

On July 26, 2016 at 8:17 AM, Denny said:

I am outlining my house with pixels this year and will need to use power injection and null pixels due to the distances involved from the controller.  I know I need to install null pixels every ten feet or so and also power injection about every fifty pixels.  Do I need to use a separate power line or can I simply tap into the 12 volt power lines in the main line from the controller?  With my pixel trees and grids, I have always run a separate power line from the power supply, but if I can just tap into the line from the controller, it would make wiring a bit simpler.  

Hi denny

i understand your question and the answer is no. At least that's my answer. The board is not ment to power inject. I can tell you what will happen: your whole prop will be dim and look like it needs power injection  

Your method of injecting at 101 pixel is perfect for a 150 pixel run. 

Do yourself a favor and bench test the distance from controller to first pixel before you go using nulls. Once you introduce a null pixel, it will only regenerate the data for about 8 feet ( my experience with 2811 strips) from that null. I have 2 runs that are almost 50' from controller and do not need nulls. 

[Denny]

4 hours ago, saxon said:

Hi denny

i understand your question and the answer is no. At least that's my answer. The board is not ment to power inject. I can tell you what will happen: your whole prop will be dim and look like it needs power injection  

Your method of injecting at 101 pixel is perfect for a 150 pixel run. 

Do yourself a favor and bench test the distance from controller to first pixel before you go using nulls. Once you introduce a null pixel, it will only regenerate the data for about 8 feet ( my experience with 2811 strips) from that null. I have 2 runs that are almost 50' from controller and do not need nulls.

Thank you, that's the information I was looking for.  

Thanks, also, for the tip on nulls.  I have been putting these pixels up to outline the house and thought I would use Halloween as a test for them.