RGB Nodes - Power Injection

[pyrotech]

Help please.

 

So, I am new this year to RGB.  I am building a mega tree and I have a couple of questions about power injection.  

 

First off, I have already read through this...    (several times) 

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

 

But, I still have a couple of questions. 

 

First...look at the photo from the above mentioned website.   

 

This shows three strings of nodes.  Coming out of the controller to the first set of nodes is Data, ground, and power.  Then, out of the first set, Data, power, and ground continue to the second and third set.  Also in the picture, ground and power are being tied into the beginning of the 2nd set, 3rd set, and the end of the third set.   This does not look correct to me.  Shouldn't the power line NOT continue in between the sets?  Therefore, in my mind, it should be....power, data, and ground out of the controller to the first set, data and ground out of the first set and into the second set.  (this is where power would be injected, along with joining the grounds together.  and then the same for the third set.

 

 

Thanks,

Tim

 

[jerrymac]

Yes the picture is correct.  You are refreshing the power (forward and backward) at the injection point.  Depending on the number of pixels, size of wire and distance) you might be able to only inject power between the 2nd and 3rd  string only, or at the beginning and end of the strings only.   

[k6ccc]

When you are running a single power supply, it's no problem at all to tie all the + voltage lines together.  When you are using multiple power supplies (look farther down the referenced page), that's where the + voltage gets separated.

[pyrotech]

Hey Guys,

 

Thanks for the help.  I really appreciate it.  

 

A couple of follow ups if you don't mind.   I attached three pictures.  The first one (labeled "Power Injection 1")  is from the "doityourself" website.  The second and third pictures (labeled "Power Injection 2" and "Power Injection 3") is what I was thinking of doing.  Oh, BTW...I have 75 nodes in each of my bundles for a total of 150 nodes (12v).  Because I have 75 nodes in each string is why I injected power on the first string of nodes as well as the second string of nodes.  My controller can only handle powering up to 50 nodes.  

 

Question #1...does what I am proposing in picture #2 work?  Is there anything wrong with doing it this way?   

Question #2...does what I am proposing in picture #3 work?  Is there anything wrong with doing it this way?

 

 

Thanks again,

Tim

[k6ccc]

Assuming the pictures came in the right order on my phone, I would go with option 1. Longer answer when I get to a PC.

[k6ccc]

OK, now on a computer so easier to type more than a few lines.  The reason I said I would go with option 1 is that with both options 2 & 3, you would be powering as much as 75 pixels from the point of power injection.  Although it would likely work OK, you might start getting color degradation or in the case of smart pixels, data dropouts due to low voltage.  You don't want to get it all setup and find that whites look more pink at the ends, or worse, data dropouts.  This is one of those cases where brute force is a good time.

 

In my year round landscape lighting, I have dumb strips that are in a circle so both ends are right next to each other.  One is 6 meters and the other two are 5 meters.  In all three cases, I feed power to both ends.  I also have some smart strip that started off with about 7 meters from the E6804, and the ends were a bit pink when full white.  I ended up feeding power about 2 meters from the far end (that point being easy from a conduit standpoint).  No more pink - except when I wanted it to be pink.

[pyrotech]

Hey Jim,

 

Thanks for all the help.  Very much appreciated.

 

Tim