LED Christmas Tree Lights

Discussion in 'The Projects Forum' started by Bah Humbug, Dec 2, 2010.

  1. Bah Humbug

    Thread Starter New Member

    Dec 2, 2010
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    Need help pinpointing problem with LED Christmas tree lights. I have a strand that lights up when plugged in. This strand will stay on for a few minutes, then go off. They will stay off for a couple of minutes and then come back on. This happens continuously. I have looked at the wiring and bulbs and cannot find a problem. I am wondering if it could be in the resistor for that strand? Sometimes when I move it around, it seems like the lights go on and off, but not all the time. If it could be in the resistor, can that be replaced easily? Any info/guidance greatly appreciated.
     
  2. iONic

    AAC Fanatic!

    Nov 16, 2007
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    It almost seems that it could be heat related. Don't know if they use thermistors or not.
     
  3. Bah Humbug

    Thread Starter New Member

    Dec 2, 2010
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    I was thinking somehow it was heat related. It's almost as if as soon as they heat up good, they go out. Just before they come back on, they'll start flickering then come on like they're supposed to. They just won't stay on.:confused:
     
  4. beenthere

    Retired Moderator

    Apr 20, 2004
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    Have you tired to find the one bulb that controls the flashing? It's usually marked in some way. If that is defective, it might cause the problem.
     
  5. Bah Humbug

    Thread Starter New Member

    Dec 2, 2010
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    The lights are not the blinking light variety, although I did look at all the bulbs to make sure a blinking bulb wasn't accidentally inserted when manufactured--I just got the tree last Christmas. When it was first put last year, the lights worked fine for a while. After a couple weeks this started, but since it was almost time to de-decorate, I didn't worry about it. I guess I was hoping they would miraculously work this year!:)
     
  6. wayneh

    Expert

    Sep 9, 2010
    12,126
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    I can't see any other explanation besides heat. Since it's not meant to flash, you must be losing continuity as it warms up. Other than wiggling each bulb when it's off, I can't think how else to fix this. I assume the string goes off if a single light is removed? You might try replacing one bulb at a time. Brute force.
     
  7. thatoneguy

    AAC Fanatic!

    Feb 19, 2009
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    Does the plug get warm?

    Some of the LED Light strands I've seen actually have a small power supply in them for the DC needed to run the light strand.

    Some are the simple resistor/cap limiters with a diode, others are full switch mode power supplies, though those tend to be on the multifunction strings that have a "control box" a few inches from the outlet that allows choosing what pattern the lights will run.
     
  8. iONic

    AAC Fanatic!

    Nov 16, 2007
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    Not sure how much you paid for it, but Christmas will be over and done before you fixed it. You might just be better off buying another set and repair it on some rainy summer day.


    iONic
     
  9. Bah Humbug

    Thread Starter New Member

    Dec 2, 2010
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    iONic-I think you're right. I've come up with one solution--I'm getting ready to turn the tree around so the lights that are going on and off will be facing the wall and make it less noticeable. ;)
     
  10. sparky46kv

    New Member

    Dec 4, 2010
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    Some times the mystery can be blamed on "country of manufacture"



    "Fix it till it's broke"
     
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