2811 Strips killing the first LED

coryh

New elf
Joined
Oct 23, 2013
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2
Hi All,

Im building a display with about 3500 2811 LED's on strips. I'm using these strips in 3m lengths injecting power at both ends.
I seem to be having a lot of troubles with failures. Out of the blue a section will stop working, if I cut out the first LED from the strip all seems to work ok again... While I expect a certain amount of failure from the chinese made stuff I have removed the first about 15 times now, sometimes 2 or 3 times from the same strip.

I would have thought if it was a power related issue I would see failure on other LED's in the strip not just the first one correct?
I'm using an 8 channel SD card controller - eBay sourced.
I have nothing in between the controller and the first except 2m of smallish wire, should I be running a cap to filter spikes etc?
I'm using Switch mode PSU's for power supply to the display.

Any help of suggestions would be appreciated.
Cheers
Cory
 

AAH

I love blinky lights :)
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Dec 27, 2010
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I would be checking the power supply voltage. If they are 5V pixels then the 5V is pretty critical. Higher than 5.5V WILL kill the pixels. If it is just above that threshold then the light duty wire and the voltage drop down the wire might be saving you from more grief.
 

DanJ

Full time elf
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Aug 14, 2013
Messages
184
Rowan--didn't know that; hadn't heard that yet. Soooo much to learn about RGBs. It makes sense, though, if you think about power onto/off of the RGBs in pure step changes (off/on).. Thanks.
 

fasteddy

I have C.L.A.P
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plugging pixels in when they are powered up is a big NO NO it will cause damage to the first pixel, this has been mentioned many times in the past in many different threads but with all the info needed to learn to run pixels it can be easy to miss.
 

coryh

New elf
Joined
Oct 23, 2013
Messages
2
Hi all,
Thanks for the responses!
The SMPS seems to be giving a good 5V so i'm pretty confident it's not that, but I had been plugging in the stips whilst power was on, seems like this is a no no :-[ .. Have you guys seen this problem before?
Cheers
Cory
 

fasteddy

I have C.L.A.P
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I am telling you this from 5 years of experience and I have killed a few in the past by this method (im now much more diligent), and its just not an issue with the 2811, so the general rule is never unplug or plug in pixel lights when powered.
 
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