Confused with Pixels

[BlackwolfK9]

If this is the wrong spot, I'm sorry, so if someone needs to move it thats fine.

My problem, I have a pixel controller which connects to a 50 node pixel prop by 2 18" pigtails.  Then a 10' piece of 3 wire 18gauge with pigtails running to a second similar prop with 50 nodes.  If I connect the first 18" pigtail to the controller and then exit the 1st prop and run the 10' piece of 3 wire to the second prop, the pixels on the second prop blink, first prop is fine.  But, if I move the 10' piece of 3 wire between the controller and the first prop and connect the 2 props together with the 18" pigtails, all works fine.  I've tried different props, shuffled all around, results are the same.  Any ideas, I'm stumped.

[sticks4legs]

low voltage and data signals can be very touchy when going over extensions.  What type of wire is the extension?  I have some that work fine with solid core but as soon as I use stranded I get pixel flicker.

I also find the signal coming directly from a controller can travel further than from a pixel...Don't know if its true or not but that is my findings.  I can run 20-25 feet from my e682, but I'm lucky to go 20 from a null pixel

[BlackwolfK9]

The extension is rgb 18 wire,  Now if have same type of props on a different port on the same controller using spt 1 for extensions and they are 2-3 times longer than this and all 3 work fine.

 

[kryolla]

use a y splitter and split the power between the two strings, the data would still need to be connected from the end of one string to the start of the next string.. See if that helps

[k6ccc]

What type of pixels?  Some of the technologies will work over quite a bit longer range.  Two things to check on.  First is voltage, and the second is data.  With 100 pixels being powered from the end, you may have too much voltage drop at the end.  Turn the lights on (as much full white as you can realizing the lack of control on the second prop).  Measure the voltage at the far end of the second prop.  For an easy fix if there is too much voltage drop, and if you have unused ports on that controller, connect only the power and ground signals from a second port and run those to the power and ground at the far end of the second prop.  I'm doing that with a SanDevices E6804 that is part of my year round landscape lighting.  It only has two of the four outputs in use and never will use the other two.  I am using outputs three and four to supply power injection to the end of each of the two operational strings.  The other thing to note is that 100 pixels on one output MAY be more current than one output can supply when the pixels are full white.  Depends on the pixels being used and the controller.  For example a 12V 36 watt string of 50 pixels is three amps at full white.  Many of the pixel controllers are rated for four amps per output.

As for data, as a general rule of thumb, most of the pixel controllers can output a stronger signal than pixels.  That means that you may get for example twice the distance from a controller than you can from another pixel.  You may need to add a null pixel.  Since most of the controllers can't be programmed for a null pixel in mid stream (only at the beginning), you simply change your configuration for the second prop to be pixels 52 - 101 instead of 51 - 100.  Pixel 51 is midway between your two props and never gets turned on.

 

[BlackwolfK9]

Problem solved for now. Instead of using the rgb 3 wire 18 gauge, i tried 2 lenghts of spt -1 (only used 3 of the 4) and all works fine.  At first I thought, "why would this work, same gauge wire"...but the 3 strand rgb wire appears to be aluminum or something similar, whereas the spt is copper.  And don't you have to upsize for similar load carrying when going from copper to aluminum?  But all is working now.  Matter of fact I have a set of 3 of the same props much farther from the controller and much farther apart, connected with spt1 and they work great.

Thanks so much for all the input, and using spare outputs for power injection seems like a great idea!

Edited November 30, 2016 by BlackwolfK9

[sticks4legs]

Good you got it working

[kevinob]

"  For an easy fix if there is too much voltage drop, and if you have unused ports on that controller, connect only the power and ground signals from a second port and run those to the power and ground at the far end of the second prop.  " 

 

.....

thanks for that info... may solve a problem I was anticipating to rear its head soon... 

 

I also did not think of using some of the SPT1 I have lying around as extension for RGB.... thanks!