How long of a pixel string

[jerrymac]

With e1.31 controllers now containing from 2 to 16 oulets with the somewhat limited distance from controller to pizel , what is the advantage or disadvantage of very long strings (strips) assuming you inject power along the way.
ie. house outline.. Controller in the middle and 8 runs of 5 meter strips? -vs- numerous smaller controllers with 5 or 10 meter max.?
If you choose, could you not make 1 single run of say 40 meters from a single output injecting power at appropriate places?

 

[GoofyGuy]

Advantage would be less controllers, less setup, less cases in the yard. This doesnt save time really in software really but mostly the layout of the house. Andy is a great example of this as he used the p2 and long strings with power injection. Less controller, less cost. In the defense of the pixels, my 2801s were garbage, constant failures, the 2811 I didnt have a single one die. Does that mean they wont?
The disadvantage is if you have a 680 pixel long string going all over the place on your house, and lets say pixel #3 dies. You just lost that entire string. My whole house used just under a 1000 pixels this year. If that 1 pixel that early in the string died, then 3/4 of my display is dark. Against say a P12 or E682 where each output is 1 universe, the most you lose if a rogue pixel decides suicide is the way to go, you lost 1/10th of your display.
With poper managment I could have decorated my whole house last year with 1 output of a P2, imagine if 1 pixel died in the show, thats a lot of work for that 1 bugger. Dont get me wrong I still have to replace, but in the mean time at least there would be some show going on if I split the load up.
The leaders this year for safe pixel managment will be the P12 or the E682/683. Very flexible, lots of outputs, Unicast.

 

[DeeJai]

well, the main determinations for the max length of your pixel string will be
a: size of house (distance from controller)
b: power injection
c: maximum channels per universe

You can theoretically have long runs of upto 170 pixels per universe. In theory that is. In practice, it is far better to drop the max pixels per universe to 150 or less. Now 150 pixels is 450 channels, or is equivilent to about 3 x 30led/m (5m length) pixel strips.

As discussed elsewhere, dependant on the type of pixel you use and the voltage requirement, you will need to inject. For 2801, a good rule of thumb is every 50 pixels.

Also, dependant on the distance from controller to first led of each universe, you may need to run a null pixel, to ensure the data arrives where its supposed to. 2811 has less of an issue with this over 2801.

So there are many contributing factors to the max length of a string, but food for thought.

 

[ԆцряєсϮ]

You can theoretically have long runs of upto 170 pixels per universe. In theory that is. In practice, it is far better to drop the max pixels per universe to 150 or less. Now 150 pixels is 450 channels, or is equivilent to about 3 x 30led/m (5m length) pixel strips.

Why "In Practice" is it better to only run with 150 pixels per universe?
Why wouldn't you utilise all available channels in a universe if your particular element allowed it?
Can you explain further?

 

[DeeJai]

Reasons behind my suggestion in "practice" was due to input i have received from others, including from one of the pixel board manufacturers stating, that there could possibly be data transmission issues with larger pixel counts on the one universe.

150 pixels is an easy number to use when multiplying and for planning injection (re. every 50 pixels or so)

Not saying you cant use all 512 channels (or 510 for pixels) just saying, when you have 4, 8, or 12 outputs it is far better to spread the love rather then everyone trying to escape through the one exit.

If you have enough pixels to completely fill up a controller, your probably wanting to get another controller anyway.

 

[Kaden]

How long of a pixel string

I think the artificial 1 universe limit is a thing of the past now.

If you don't mind the risk of losing all the pixels after a failed one and don't mind the refresh/data rate being slower, then I would comfortably put 500 pixels on a single ECG-P2 output.

But in the end all you can do is test it for yourself.