Cut Pixels/Nodes will not come on

[alphafilter]

So I am running into a weird issue or maybe I am doing something wrong since I am new to this.  I am working on wiring some pixel nodes up and it required me to splice three strands together.  The last strands are only 10 pixel nodes in length.  I have two of these and neither one of them will light. I had them wired into my strand and that didn't work so I disconnected them and connect them straight into the controller that does not work as well.  The strands that I am splicing into work fine.  These as 12v 2811 pixels. There are only 60 pixels total in the string. Any ideas or suggestions on this one?  Or maybe I am overlooking something obvious.

Thanks for any tips/assistance.

[Phrog30]

If I'm reading correctly you have 60 pixels and in all cases the last 10 will not light up? It's probably because your controller is set to 50 pixels on that output. What controller are you using?

By the way, there is a right and wrong way to wire up pixels. There is an input side and an output side.

James

Sent from my Nexus 7 using Tapatalk

[t.jo13t]

I would also check that you wired to the right end as it is easy to get mixed up. Been there done that lol

[alphafilter]

Thanks for the reply's. 

So to answer some questions. I have 50 pixels and the last 10 will night light correct however these 10 will not light when connected directly to the controller (i.e only 10 pixels). These are connected to a pixlite16.  Connecting the 50 pixels to the same channel works fine but the 10 by themselves will not.

Now to wiring.  I could have this confused.  What I have is a 12V 12mm RGB nodes from holiday light express.  The wire is green from what I can tell inside the pixel it is labeled 12v/Data/GRND there is a "small chip" side and a "Large Chip" side.  I have my input going into the "small chip" side.  This seems to work fine on the other strings it is just with these two short strings that it is not working.  I have not tried going into the "large chip" side I guess I could try that.

Thanks again for the assistance.

[Phrog30]

I'm not sure on your pixels, but mine, and most from what I've seen , the input side is the side with the labelling. 

I'm sorry, but I'm not following your description.

Sent from my Nexus 7 using Tapatalk

[alphafilter]

I apologize for the confusion.  Attached are some photos.  Both "sides" of the chip having writing on it where it is designating 12v/Data/Grnd (12v and Ground on the outside data in the middle)

One chip is smaller than the other on the circuit board depending on which side you are looking at.  On the "small chip" side that is where I am providing power and data from the controller. This seems to work fine on my other strands however I have two of these 10 pixel strands doing the same thing.  I provide power and date on the "small chip" side with them directly connected to the controller and they do not work. 

I just went back and looked at some of my other models and I do have a 20ct strand working fine so I am wondering if this is too short or too few pixels if there is such a thing?

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[danj]

Totally wild guess-the 10 nodes that do not work <could> have the first pixel bad, keeping the rest of the pixels from coming on.   The data stream runs thru each pixel, so one bad one can definitely goof up the rest.  I have not seen this type of action (not lighting at all) though, due to a bad pixel--I have seen some flashing and discolorations but not totally "off"...  It might be worth cutting out the first one out and testing the nine remaining pixels.   That is a really great thing about nodes; really easy to cut out/solder into...

[RandyS]

I just went back and looked at some of my other models and I do have a 20ct strand working fine so I am wondering if this is too short or too few pixels if there is such a thing?

Don't worry, there is no 'too short' of a string.  1 or 50 should act the same.  Try as mentioned, cutting out the first Pixel of your string of 10 and test again.

[Gilrock]

Just look at the chips on the pixel string that works and then you'll know which side is in/out.

[kentd]

There are several modes that can happen:
1.  The pixel lights and passes data (Normal)
2.  The pixel does not light but still passes data
3.  The pixel lights but does not pass data
4.  The pixel does not light and does not pass data (Bad Pixel)
As mentioned before you probably have a bad pixel

[RandyS]

A bad pixel can just happen, or it can be caused by reversing polarity.  If the polarity is reversed, it will usually kill the first pixel in line.

[bpducman]

Take 1 led "Pixel"  no more than 1 and do your experimenting on just that 1. Usually the small chip is the in side. If the pixel is made with clear epoxy you can usually see a gnd, +, D near where the wires were soldered in .

Just because the wires look aligned going in... they may not be in reality especially if it is in black epoxy.

on the out wires use a volt meter and look for the solid 12vdc at the + and gnd. If you can get the led to work when  running a sequence then you can use the meter to look at the D and gnd. You will not see data, but you can see a change in the dc voltage as the data changes. It would take a scope to really see the data.

If you can do all this with a led that does work now and you can't get any of the others to work then they are bad.

everyone has popped leds... always best to pop a few rather than a string of 110.

Not that I have ever done that......Lol

[alphafilter]

Thanks all for the suggestions and tips etc.  I ended up figuring this out and it ended up being rookie mistakes on wiring and paying attention to settings etc.  I'll chalk it up to lack of sleep working on this after work every night.  I really appreciate all the feedback and tips and have added them to my notebook for future troubleshooting reference.

Thanks again.

[danj]

Glad you figured it out!   None of this stuff is really hard, but there are definitely a LOT of little details to attend to, many of which can just totally mess things up!!!