72led/m strip weird result

Madko

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I have connected some 72led/m strip up to a 2811DC15 board with is coming off universe 12 of a P12R.
The first 4 outputs from the 2811DC15 board is doing well. Driving the strips and in the correct colour. However output 5 when running colour blue seems not working properly. The first 6 or so LEDs of the strip are blue but the fade away pretty rapidly. Each other colour red and green are fine. Obviously white is also effected.


I have checked connections and that seems to be fine. Looking for some other ideas.

[SIZE=78%]Is there any setup I need to do for the 2811DC15 board?[/SIZE]


All other outputs seem ok.
 

AAH

I love blinky lights :)
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Try swapping the channels with the strip and see if the problem follows the strip or the channel. I'm thinking that you may have something dodgy up with the strip as it should be uniform down the length of the strip.
 

AAH

I love blinky lights :)
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Replying again instead of editing in case you have notifications on.
Just a thought that may cause the fading you are seeing. You may have a short on the blue channel and you are losing volts down the line in a big way. Check to see if the strip and/or the mosfet are getting hot when running that blue section.
 

Madko

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More testing show I have a short either in my plug I soldered or within the strip.
It's more likely ( and I'm hoping) to be in the plug I soldered.


Has anyone got any strips from Ray that has had a short in it?
 

AAH

I love blinky lights :)
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I have been looking at some strips for ryanschristmaslights and 1 of them had an intermittent short which was caused by a cracked flexible pcb shorting to 1 of the 5050 leds.
 

Madko

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Yeah, looks like I have a short somewhere along the strip. How do I find where it is along the strip without cutting each individual section off until the short disappears?


No visible sign of a short.
 

AAH

I love blinky lights :)
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With the strip I am playing with I have used a safety pin to pierce the silicon and multimeter to isolate it.
 
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