pixels randomly flashing

[Aurbo99]

I'm not sure exactly where this issue falls under.
never had this behavior before.

FPP 3.5.4
e682 fireware 4.033
ws2811 pixels

Scheduler running repeat 15min sequence only between 5pm to 9pm

one string of pixels are "twitching" , random pixels, random colours on only one string, this occurs while scheduler is not running the sequence

I've swapped out the string already.

Next step would be to replace the e682 unless anyone may know another cause.

[pmiller]

You didn't mention if they are 12 or 5 volt pixels. The newer 12 volt pixels are sensitive to voltage especially at 12 volts. They are less sensitive to lower voltages. I turned the voltage down to 11.8 on all my 12 volt pixels. Even though the pixels aren't on there is still voltage going to them. I can't remember if your firmware allows for pixel timing but the current version of firmware for the 682 is 5.030 and allows you to control each of the 16 outputs separately. I set my pixel timing at 200 but I've heard others set the timing even higher to get rid of random flickering.

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[MartinMueller2003]

How long is the wire from the controller to the first pixel on the string having problems?

[Doug C]

I have the E682 and ws2811 and had the same issue last year.

Upgrade to the latest ver 5 of the firmware and increase the timing to 300ns, this solved all my random flashing problems with the E682.
Doug

PS it has nothing to to with the PI, I was using a controller and the lights only to reproduce and the freezer as it only appeared when the lights were cold. these were pixels bought back in 2015 also but I am not sure age is relevant. try the upgrade first.

[MartinMueller2003]

I have the E682 and ws2811 and had the same issue last year.

Upgrade to the latest ver 5 of the firmware and increase the timing to 300ns, this solved all my random flashing problems with the E682.
Doug

This only changes the interframe gap. This means you may have had alignment issues. Truly random flickers are caused by signal integrity issues that are often solved by changing the resistor packs or adding driver / null pixel devices.

[JP90]

As MartinMueller2003 said the cable may be too long. I had the same thing happen when I placed a 15' pixel cable on top of an AC power cable because there was no other way for me to run that pixel line, what I had to do was replace the resistor pack that came with the E682 (270 ohm) with a 100 ohm and that took care of the problem, you don't want to go any lower than 100 ohms because that resistor pack protects the driver IC in the E682 from shorts that might damage that IC. If the driver IC is in a socket you could swap it with another one on the board to see if that IC is bad or just move that string to another output.
Gary

[tjetzer]

Steve,

Are you using only one of the four outputs or are you using more than one of the group? I had the same issue but it affected all four outputs of the group. Turned out to be a buffer chip.

I'm not sure exactly where this issue falls under.
never had this behavior before.

FPP 3.5.4
e682 fireware 4.033
ws2811 pixels

Scheduler running repeat 15min sequence only between 5pm to 9pm

one string of pixels are "twitching" , random pixels, random colours on only one string, this occurs while scheduler is not running the sequence

I've swapped out the string already.

Next step would be to replace the e682 unless anyone may know another cause.

[tjetzer]

This is not true. Regulated 12v pixels have no problem with 12v or more. Resistor based 12v pixels have issues with 12v or higher.

You didn't mention if they are 12 or 5 volt pixels. The newer 12 volt pixels are sensitive to voltage especially at 12 volts. They are less sensitive to lower voltages.

Sent from my SM-T710 using Tapatalk

[MrDudeMan]

i think you should swap out the resistor packs.
easiest thing to do and symptoms really sound like thats the issue.
assuming of course you have 100ohm resistor packs handy...
if not, for a test, you can solder 2 resistor packs together(in parralell) which will effectively halve the resistance of the resistors soldered together.

[Aurbo99]

You didn't mention if they are 12 or 5 volt pixels. The newer 12 volt pixels are sensitive to voltage especially at 12 volts. They are less sensitive to lower voltages. I turned the voltage down to 11.8 on all my 12 volt pixels. Even though the pixels aren't on there is still voltage going to them. I can't remember if your firmware allows for pixel timing but the current version of firmware for the 682 is 5.030 and allows you to control each of the 16 outputs separately. I set my pixel timing at 200 but I've heard others set the timing even higher to get rid of random flickering.

Sent from my SM-T710 using Tapatalk

12vdc. purchased 2015 or 2016

I will flash to 5.030