Pixel Strip LED count question

[pblais]

I have a question concerning LED counts on pixels strips.

Let's say I have a strip that has, for example, 240 LEDs on it and I plan to use it in a HUGE arch.  (I know.. this is a made up case for this question).   Anyways, 3 LEDs are controlled by one chip on this strip.
SOOOOOOOOO  when I want to tell XLights how many LEDs there are on this strip, I think I have to tell it 80.  Which would be 240LEDs divided by the 3LEDs per chip... 
But now for current reasons, how many LEDs do I tell the 16V3.  240 or 80?

Thanks
Pierre

[Gilrock]

All controllers and sequencers only want to know how many controllable pixels there are so it's 80 everywhere.

[pblais]

All controllers and sequencers only want to know how many controllable pixels there are so it's 80 everywhere.

Yes  but what about for current and power insertion reasons...? Doesn't the 16V3 need to know this?

[Gilrock]

I don't know of any feature on that card that adjusts based on # of leds.

[pblais]

But what about power insertion?

[Gilrock]

That's up to you to figure out where you want to power inject.  There will be no numbers you type into a controller or sequencer regarding power injection.

[pblais]

I am sorry...  I guess I should rephrase my question....

Whe it comes to power insertion.  In my example do I use the 240 actual LED count or the 80 chip count?

[Gilrock]

Problem is not all strips are the same when it comes to power requirements.  Most strips will work just fine by themselves so its when you start daisy chaining you need to think about injecting.  A good rule of to just look at the current draw specs for the strip and try to make sure you have less than 5 amps in-between injection points.  So if a strip says it draws 3.5amps you probably would want to inject before attaching a 2nd strip.

[pblais]

Ahhhh   ok  thanks.
I am not sure I can find the current specs on these strips.  So if I turn it on full intensity white and use a meter to measure the current, I can make more educated decision later.

[cybi257]

If you want to play it safe, think about injecting power at every 50 pixels. I have gone much more, but powered on both ends so the power is coming in from both sides.

One thing to note, it's not just about the dimming of lights you need to worry about either. At least by my experience. Some people will just lower the intensity, which helps remove the yellowing/dimming, but if you are getting dimming at 100% intensity, the other thing I am making a point on, is the Data Signal travelling through.

I've had times when it all looked great, but then later, I had flickering. This flickering wasn't caused by the LEDs not getting enough power, but the chips not getting enough power to keep the signal going from one element to the next. A simple injection point in between the elements (even though there were few LEDs), solved that issue.

Hope this helps as I kept thinking I had other issues with the lights themselves rather that the data signal not being boosted.

-Tim