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Fading issue with some LED's


TraceWilson

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Hi all,



Not sure if this is the right place for this question, but here goes...

Last year I purchsed tons of red, gree, blue, orange, white, and icicle LED's, and running with the 16 channel director board (Green, Firmware v4.01) everything went beautifully last year.

This year I expanded with a load of purple LED's from the same manufacturer, but these simeply do not seem to want to fade. At the beginning of the fade sequences, they actually seem to brighten a bit, then just turn off. Same type thing happens on the fade up's...nothing happens at the beginning of the fade up, then BANG, they come on full intensity.

Any thoughts would be appreciated. FYI, I've post this questin at the PC LED forum as well, but throught it may be better to cast a wide net :D:D

Trace

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If that does not help, (or they have a polarized socket) then they are probably using capacitors to limit the current through the LED string, instead of resistors. As you start the fade, the phase angle dimming creates harmonics. Since the harmonics are a higher frequency than the 60 hz the capacitor is sized for, current through the capacitor and LED string actually goes up!!! Once the voltage at the firing phase angle is less than that of the forward bias for the LED string, they will suddenly go off.

Because of the harmonics, and the increasing current through the capacitor current limiter, continuing to try to fade this type of LED string will likely cause them to fail.

- Kevin

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Trace,

I use the same LEDs and had the same problem last year. I added a resistive load and everything worked fine. You can use single C9s, candle lights, or something small thats incandescent. Also, you can make terminators:

http://crazylightlady.us/TerminatorsHow-To.html

Regards,

Roy

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Wayne K wrote:

TraceWilson
where did you get your led lights from? I am looking to switch this year also.

Wayne


I bought all mine from Laure at Reinders (http://www.reinders.com).

2 yrs ago they were giving a 10% discound to PC members, but I don't think that holds true any more, but you can always ask. So far, they have been great to deal with.
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DrNiceGuy wrote:

Trace,

I use the same LEDs and had the same problem last year. I added a resistive load and everything worked fine. You can use single C9s, candle lights, or something small thats incandescent. Also, you can make terminators:

http://crazylightlady.us/TerminatorsHow-To.html

Regards,

Roy


Thanks!!! I think I'll try a small nightlight and see how that goes.

Trace
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