I posted this as a comment to an older thread I started,

(Christopher Kirkman) #1

I posted this as a comment to an older thread I started, but it probly got lost in the shuffle. Short version is that I was seeing flashes in my strip after a couple hundred LEDs. I took the strip down off the roof, tested for power issues, looked for bad joints, cut out a handful of LEDs and what I’ve got now is this:

SOMETHING is bad SOMEWHERE. When I pinch or twist areas near where I start to see flashing and randomness, it changes and data seems to get past the hump, but only briefly. Is there something I should be visually looking for, or am I stuck guessing and cutting out LEDs until they work?

Generally speaking, I can get one lit pixel to travel down the line pretty good, but when I run them all, like in the generic demo, I start seeing this mess.

(варешяф рйезот) #2

As my friend says: electronics - it is science about contacts (join points) ))
Try to resoldering leds - thats one that I think for your case.

(Dushyant Ahuja) #3

Try adding a small capacitor on the power rails. Also check the solder joints.

(Mike Katchmar) #4

Does it work better if you lower the brightness? If OK at a lower brightness, then it’s a power issue (can’t see a separate power supply in the video). You could chop out the section where it doesn’t work well and re-solder. But in my opinion those strips are “cheap” enough that it might be worth it to just get a new one instead of going to all that trouble. The waterproofing will never be the same.

The consensus in the extreme Christmas decorating scene has been to avoid LED strips, most favor the sealed (IP rated) individual pixels after experiences like this. I have the same style strips outside, but they are inside tubes, primarily for diffused effect, but it doubles as environmental protection.

(Greg Brown) #5

@Mike_Katchmar can you elaborate on your setup? You mentioned your pixels are in tubes…do you make the tubes or purchase? My Xmas lights will be Alitove WS2812 that come in weather strips. I’m assuming this is enough protection from the elements, but like you say, no diffusion.

(Mike Katchmar) #6
(Christopher Kirkman) #7

@Mike_Katchmar I’m using a separate 5v 15a power brick and I’ve got a 100uf cap on the rails. They’re inexpensive, but I wouldn’t call em cheap at 40 bucks a pop. My intention was to use these year round for different events and holiday and, for a while, they worked great. I suppose I’ll keep chopping and soldering till I get them working well.

Oh, brightness didn’t seem to make an difference. They still failed at the same point in the strip and pinching that area still had that odd effect.

(John Rhoades) #8

Are you grounding the LED strip to the same ground as the board running it? I had the same flickering with my own strip, and it would work better when I was touching parts of the setup, like the battery or board. There’s a note in the guide about that, specifically for the WS2812B strips.

(John Rhoades) #9

@John_Rhoades To clarify, the strip SHOULD be ground to the same ground as the board.

(Christopher Kirkman) #10

@John_Rhoades yes, grounded all around. - see below for more.

(Christopher Kirkman) #11

I spent a portion of Sunday cutting out a handful of LEDs (I lost track of how many) that exhibit bad color, were just dead, or were the first in a line of badly flashing segments. What I’m left with is a slightly shorter, but so far, functioning strip. I’m assuming at some point after whatever animal poked its teeth/beak into the strip back when this all started, moisture probably found its way in and started doing it’s ugly dance to the delicate bits.

I’ve resealed everything best I can and after running a couple more tests, I’m gonna be putting them back on the roof, hopefully for at least one more season. Thanks for all the suggestions!

(Chris Chris) #12

How many leds? I had something similar and solved with connecting 5V on both sides.

(Christopher Kirkman) #13

Before this bad LED culling, I had an even 300. Not sure how many are left. I avoid running them at full brightness since I can’t get power injected further down the line very easily but otherwise I’ve had pretty good luck.

(Chris Chris) #14

@Christopher_Kirkman1 I suggest to do a try to connect at both sides. I have multiple led projects done and sometimes it was needed and sometimes not. I would be good to exclude this.

(Christopher Kirkman) #15

@Chris_Chris it’s just not an option for me. The strip is on the eaves of a roof about 10 feet up. Running another 15ft set of wires down the line is not just a hassle, but introduces too many other potential problems to be worth the effort.