Pixel strip power injection

[sticks4legs]

Looking for a little assistance. Now that I have finished my leaping arches I'm beginning to layout/plan for some RGB pixel strips on my eaves. (12 volt Ray Wu 2811). Some of my lengths have to possibility of reaching 20-30 feet plus a distance from my controller and power supply. Thinking that I will need some power injection I'm curious if the method I'm thinking of will work. Currently I soldered 4 core,( using 3 wires) weather proof connectors on my arches, worked great however no needing power injection.

For the strips on my eaves can I solder both a 4 core connector ( only using 3 wires) and a 2 core connector ( +\-) on the input side on each strip. That way the data feed will be consistent and I can run some 14g wire from the power supply to the 2 core connector.

Basically most strips would have a 4 core and 2 core on the input side and a single 4 core on the output.

I'm using e6804's so I'm trying to take advantage of the universe count with limited pixel output from the board.

[plasmadrive]

The best way it is to use something like a 24vdc supply and put it where you need it to be and then use DC-DC converters for the power injection.  This way voltage drop across the wire is far less an issue and you can run smaller wire.

 

You would of course maintain common thru out the entire string. Data can go in and out as normal.  Most strips come in 5 meter lengths.  I have only used the 5v version and about 1.5 m is all you can use and maintain a really good CW with all on.  I am not sure about the 12v strips.  I would imagine you might get an entire strip of 5m with the 12v version.  If that is the case, you can get DC-DC converters big enough for two strips and feed between them. 

 

 

You could use something like this and you won't have to enclose it. 

http://www.ebay.com/itm/24vdc-10amp-power-supply-waterproof-LED-/111335574995?pt=LH_DefaultDomain_0&hash=item19ec1e0dd3

e0PZI

 

These are similar to what I used but mine were 5v.

http://www.prodctodc.com/dc-buck-converter-dc-24v-to-12v-5a-60w-car-power-supply-aluminum-metel-shell-case-dc-1735v-to-12v-p-192.html#.U2Imx1e0PZI

 

OR... This is a bit over kill but you won't have problems with current.

http://www.prodctodc.com/24v-to-12v-dc-converter-20a-buck-voltage-regulator-car-led-driver-power-supply-p-370.html#.U2AedVe0PZI

 

EDITED due to me not paying attention.  I removed and replaced the second link.  This one should be fine. Sorry guys and gals.  Craig

Edited May 1, 2014 by plasmadrive

[jerrymac]

I also use 4 core wire for 3 wire strips but this works with 3 core cables also. I connect 3 strips in a string (male and female connectors on each strip).  I inject power between strips #2 and #3 so power is going both ways on strip 2 (from strip one and fresh power from the end where strip 2 and 3 connect).

I connect strip #1 and  #2 together male connector to female conector (original power and data into the male connector).   At the end of strip #2, I have a short injector cable with male and female ends (this way every strip is the same, injected or not).  The short injector cable is a male one one end and female on the other (like an extension cable except it has a "T" in the middle.  On the "T": fresh power posative and negative  from the power supply and are tapped into to the possitive and negative lines, with the data line going straight through. This provides fresh power to strip #3 and fresh power to the end of Strip #2 (strip #2 has power on both ends).

Edited April 29, 2014 by jerrymac

[sticks4legs]

I like the T ideas, much easier than the extra soldering and weatherproofing.

Thanks for all the help.

[bobschm]

"Power is going both ways on strip 2"...?!

I thought you shouldn't connect two power supplies positives together. Maybe I'm misinterpreting, but if you have power from one supply coming from strip 1 and power from a seperate injector coming from the junction of 2 & 3, isn't that a conflict? Must work though. ?

[sax]

This T method works only if you use the same power supply. 2 supplies is not a good idea.

[bobschm]

So I can theoretically inject at both ends of a single strip as long as my DC convertors are powered from the same supply? Cool.

[plasmadrive]

Go to this thread https://onedrive.live.com/?cid=d9b541b0b41bfba7&id=D9B541B0B41BFBA7!227&ithint=folder,.JPG&authkey=!ALdO_FfkoPFMfFQ

 

In the upper left corner there is a PDF of a diagram with power injection.  Take a look and see if that doesn't answer your questions

[bobschm]

If I look closely at your diagram, Craig, you split the power in the middle of a string ( from brown wire to blue) so that the power from one end never actually connects to the power from the other end of the string. Jerrymac confused me by claiming that power was flowing in both directions. Maybe so, but it must dead end in the center of that string somehow, or things could go badly.

[plasmadrive]

If I look closely at your diagram, Craig, you split the power in the middle of a string ( from brown wire to blue) so that the power from one end never actually connects to the power from the other end of the string. Jerrymac confused me by claiming that power was flowing in both directions. Maybe so, but it must dead end in the center of that string somehow, or things could go badly.

Actually I did power both directions.  For example, 1&2 powered from converter #1 (brown), then 3&4 from converter #2 and so on(blue).  I split mine in the middle of two stings for power but the data went all the way thru 5 sets of strings for a total of 150 pixels per string.  My strings were just shorter than yours will be.  You can for sure feed power in between two stings with the same power supply or DC-DC converter providing you have the available amperage to do so. 

 

When you add converters or power supplies, you need to make sure all commons remain tied together in a single data string.

 

There is also one other possible option.  I didn't do it this way, but I probable could have... there is a considerable voltage drop from one end of the string to the other.  If you feed both ends with power supplies of close to the same voltage, (+/- .75v or so) you would most likely have no issues what so ever.  There is so much resistance between the two via the PC traces I doubt it would be an issue. Again, I haven't done it but theoretically it should be ok.

[TonyD]

Would this work with the 24v power supplies you had earlier even though the input voltage says 8 - 22v?

 

http://www.prodctodc.com/dc-to-dc-822v-to-115v-12v-5v-buck-voltage-regulator-mini-adjustable-step-down-converter-module-p-256.html#.U2AfC1e0PZI

 

 

[plasmadrive]

 

Would this work with the 24v power supplies you had earlier even though the input voltage says 8 - 22v?

 

http://www.prodctodc.com/dc-to-dc-822v-to-115v-12v-5v-buck-voltage-regulator-mini-adjustable-step-down-converter-module-p-256.html#.U2AfC1e0PZI

 

 

 

Oh crap!   Good catch Tony.  I was in a hurry and didn't pay attention.. DO NOT use that one with a 24v supply..

 

Here is a link to many.  http://www.prodctodc.com/car-buck-power-supply-24v-to-12v-c-22_26

 

I replace that link above with one that will work ok.. Sorry 

http://www.prodctodc.com/dc-buck-converter-dc-24v-to-12v-5a-60w-car-power-supply-aluminum-metel-shell-case-dc-1735v-to-12v-p-192.html#.U2Imx1e0PZI

 

BTW, this is the company that I got burned on with so many of my converters being bad due to manufacturing issues.  We have finally worked it out and they have found the problem and believe they have fixed it, so I will cautiously recommend them.  The ones that didn't have the manufacturing issue worked great.

Edited May 1, 2014 by plasmadrive

[sticks4legs]

Oh crap!   Good catch Tony.  I was in a hurry and didn't pay attention.. DO NOT use that one with a 24v supply..

 

Here is a link to many.  http://www.prodctodc.com/car-buck-power-supply-24v-to-12v-c-22_26

 

I replace that link above with one that will work ok.. Sorry 

http://www.prodctodc.com/dc-buck-converter-dc-24v-to-12v-5a-60w-car-power-supply-aluminum-metel-shell-case-dc-1735v-to-12v-p-192.html#.U2Imx1e0PZI

 

BTW, this is the company that I got burned on with so many of my converters being bad due to manufacturing issues.  We have finally worked it out and they have found the problem and believe they have fixed it, so I will cautiously recommend them.  The ones that didn't have the manufacturing issue worked great.

 

Thanks for the clarification, I was thinking I was missing something.  While I don't think i'm headed down that road just yet gaining all the knowledge is greatly appreciated

Edited May 1, 2014 by sticks4legs

[plasmadrive]

Thanks for the clarification, I was thinking I was missing something.  While I don't think i'm headed down that road just yet gaining all the knowledge is greatly appreciated

YOU were not missing anything.. I was missing my brain!        I just hate it when that happens..