Results 1 to 7 of 7

Thread: LED String Questions

  1. #1
    Join Date
    Nov 2010
    Location
    Dothan, Alabama
    Posts
    349
    Post Thanks / Like

    Default LED String Questions

    This is a two part post for two separate items.
    #1. I have a porch eave on the front of my house and i have to connect three led Icicle strings to complete the outline of the roof eave.
    I end up with about 4 feet of the string left and have to "bunch" it up at one end. would it hurt to simply terminate the last string by
    cutting off the excess four feet?

    #2. My neighbor and I both have megatrees with led strings on them. His tree has a few channels that started blowing triacs last year.
    The strings work when plugged directly into an electric cord. When they are connected to the controller, they blow the triacs or at best,
    a fuse every time. We use 16 small steel cables with the light strings zip tied to the cables. The trees are a spiral/hybrid with 16 strings each
    of red, green and blue in a spiral pattern and 16 strings of white leds attached vertically at each cable. I feel like one or some of the cables have
    worn through the insulation of the light strings where they are zip tied. This could, most likely short the strings together and blow the triacs.
    Does that sound possible. I am trying to figure out how to determine which strings are shorted. I thought of trying one of the ground fault
    checking plugs at the end of each light string to see if it would indicate a short to ground, but since the light strings only have a neutral and hot,
    with no ground, if it would work. Any suggestions on how we can troubleshoot this tree without having to completely re-string it?

  2. #2
    Join Date
    Dec 2012
    Location
    Hudson MA
    Posts
    3,909
    Post Thanks / Like

    Default Re: LED String Questions

    If the cable is exposed metal than all you have to do is make sure they are connected to the ground wire from an extension cord. Your ground fault tester would then work. It is very possible that the strings have rubbed through to the cable. For item one, look into the forums for an LED string shortner. there have been many discussions on this topic. My solution to extra LEDs was to stuff the extra LEDs into a static bag that contained the unwanted light.


    2019 - Just moved into a new home (yet another change of plans). Will be dim but not dark. Too much to do at the new place to leave time for a show.
    https://www.youtube.com/channel/UCyX...ttrsZNARkUce0Q

  3. #3
    Join Date
    Jan 2012
    Location
    Chambersburg, PA
    Posts
    703
    Post Thanks / Like

    Default Re: LED String Questions

    [QUOTE=Amigorick;515940]This is a two part post for two separate items.
    #1. I have a porch eave on the front of my house and i have to connect three led Icicle strings to complete the outline of the roof eave.
    I end up with about 4 feet of the string left and have to "bunch" it up at one end. would it hurt to simply terminate the last string by
    cutting off the excess four feet? YES, IT WILL BLOW THE STRING. If you want to shorten LED strings you need to add resistors to replace the bulbs you are eliminating.
    2012 - 1st year 64 Channels - 7500 LED lights - 5 sequences
    2013 - 128 Channels - 10,000 LED lights - 7 sequences (2 New)
    2014 - 201 Channels - upgrading 8 Arches to dumb RGB - 8+ sequences (1+ New)
    2015 - 240 Channels + 8 Universes - sequences TBD
    2016 - No Display
    2017 - Back in the Game - 240 Renard Channels + 12 Universes
    2018 - 256 Renard and 9 Falcon Outputs of Pixels - 16 sequences shown over 2 nights

  4. #4
    Join Date
    Dec 2014
    Location
    Springville, Utah
    Posts
    540
    Post Thanks / Like

    Default Re: LED String Questions

    Half-wave LED strings are often actually 2 or 3 sub-strings. At the plus, you will see TWO wires, but at some point (usually a slightly larger bulb socket), that changes to THREE wires. Half-way, or perhaps 1/3 way down the string, you will see another fatter socket (perhaps), but then the THREE wire part changes to TWO wire, then back to THREE wire at the next socket. Usually.

    If you can find these two-wire sections, then you can CUT the STRING into smaller sub-strings at those places. Depending on what you want to do, you may have to solder plugs on the ends so you can plug in the sub-strings.

    Let me know if you can find these two-wire sections.

    IF, however, you have FULL-WAVE strings, it gets a little harder. It can be done with some effort, but the strings can still be cut into smaller sections of certain sizes.

    Let me know if you need more help - I will nee some very detailed pictures of your strings.

    Jimboha
    Springville, Utah

  5. #5
    Join Date
    Dec 2007
    Location
    Maryville, TN
    Posts
    248
    Post Thanks / Like

    Default Re: LED String Questions

    How old are your light strings? Do you keep them over an extended period of time each year?

    Christmas light strings have a short life span as UL states they are good for three 30 day periods.

    The insulation used may be breaking down and will change with weather conditions.

    Had this problem 10 years ago using wire frame mini trees given to me with lights already attached, only isolating the frames from ground fixed the problem.

    The strings where attached using cable ties and they where tighten to much and crushed the insulation and the old light strings insulation was breaking down in humid and rainy weather.

    Dennis
    Inventor of the "LED Keeper"

    My Videos [URL="http://www.vimeo.com/Dennischerry"]www.vimeo.com/Dennischerry[/URL]

  6. #6
    Join Date
    Nov 2010
    Location
    Dothan, Alabama
    Posts
    349
    Post Thanks / Like

    Default Re: LED String Questions

    They are a couple of years old. The insulation on the wires is still good and flexible. I think the guys that helped him put the strings on the wires just pulled some of them too tight. When we store them, we loosen the wires supporting them and let them fall against the pole. Then we start at the bottom and wrap the strings to the pole with a commercial grade plastic cling wrap to protect them and keep them from snagging on anything. Then we lay the tree down for hauling it. Everything in reverse when we stand them up. It has worked great for two years.


    Quote Originally Posted by Dennis Cherry View Post
    How old are your light strings? Do you keep them over an extended period of time each year?

    Christmas light strings have a short life span as UL states they are good for three 30 day periods.

    The insulation used may be breaking down and will change with weather conditions.

    Had this problem 10 years ago using wire frame mini trees given to me with lights already attached, only isolating the frames from ground fixed the problem.

    The strings where attached using cable ties and they where tighten to much and crushed the insulation and the old light strings insulation was breaking down in humid and rainy weather.

    Dennis

  7. #7
    Join Date
    Nov 2010
    Location
    Dothan, Alabama
    Posts
    349
    Post Thanks / Like

    Default Re: LED String Questions

    This may or may not be part of the problem. We use Renard SS 24's on the Megatrees.
    I ordered the kits and built them. When I finished, i gave the controllers to my neighbor
    to add the pigtails for the channels. We used the same old SP1 18 ga wire as most do.
    I told him to make sure that the wires from the neutral side of the board connectors
    went to the side of the vampire plugs with the wide slot. I found about four channels that
    were reversed. I corrected them last night. Could this be part of the problem? If the wires
    on any of the light string ARE shorted to the cables with the "polarity" being reversed on
    a few, could it blow the triacs?

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •