1. New to Christmas lighting? Get started with the AusChristmasLighting 101 Manual:
    auschristmaslighting.com/wiki/AusChristmasLighting-101

Cutting RGB module strings

Discussion in 'RGB Lights - Intelligent Pixels and 3-Channel RGB' started by logandc99, Sep 4, 2012.

  1. logandc99

    logandc99 Dedicated Elf

    Joined:
    Jul 13, 2012
    Messages:
    1,079
    Likes Received:
    5
    Find Me On:
    Sorry if this is a stupid question but just wondered about whether you can cut strings of 20 of the rectangular RGB modules in half to get two sets of ten. I read somewhere that people have cut strings of lights into shorter sections but they blew once plugged in due to too much voltage getting to the lights (sorry tried searching for this but came up blank) but wasnt sure if this only applied to certain types of lights. I just got two sets of twenty modules but want to divide each in half to get four sets of them for my 4 candy canes i am making but I don't want to blow them up. If I can do this, anything special I have to do so they work.
     
  2. kane

    kane Dedicated Elf

    Joined:
    Dec 23, 2010
    Messages:
    1,021
    Likes Received:
    0
    Location:
    Trigg (Northern suburbs of Perth)
    Find Me On:
    No problems at all doing this - these modules are connected in parallel to the power supply (which means they all get the same voltage), so it doesn't matter if you've got 5 or 50.

    Many strings of LEDs are connected in series, and if you cut them in half, the whole string won't work.
     
  3. ShellNZ

    ShellNZ Senior Elf

    Joined:
    Jun 17, 2012
    Messages:
    856
    Likes Received:
    2
    Location:
    Karaka, Auckland, NZ
    Find Me On:
    Yeh, I just cut mine into lots of 5 modules. Reconnected once inside the corocandles.
     
  4. AAH

    AAH I love blinky lights :) Community Project Designer

    Joined:
    Dec 27, 2010
    Messages:
    2,616
    Likes Received:
    36
    Location:
    Eaglehawk
    Find Me On:
    Photos of what you are referring to and a link if you've grabbed them online will help us give you some educated info. Pretty well any lights can be chopped provided you know what you are doing. Some specific ones are designed so that can cut at specific intervals.
     
  5. fasteddy

    fasteddy I have C.L.A.P Global Moderator Generous Elf

    Joined:
    Apr 26, 2010
    Messages:
    6,501
    Likes Received:
    22
    Location:
    Albion Park NSW
    Find Me On:
    If we are refering to the low voltage RGB modules that you can get from Ray and other similar vendors then yes you can cut them up right down to a single module and still run them. The same thing can be said with RGB strings as well

    The reason why is because each module has 3 5050 leds, each individual colour within the LED is rated at a particular voltage, so for example green has a rating of 3.1 volts, so 3 LEDs in series = 9.3 volts, so each module can be independant of the other as you only need to drop under 3 volts from 12VDC supply to run each module.

    Now where you are getting confused is with the traditional strings, these generally have many LEDs in series together and have lower rated LEDs so it takes more LEDs in series to then get the LED circuit voltage closer to that of the supply voltage. A circuit limiting resistor is used to then match the LED series circuit. So if you remove or you cut a traditional string you then start to overdrive the LEDs as you now are reducing the amount of LEDs in the LED series circuit and this will make them short lived. So if cutting down traditional strings you will then need to add a resistor in the circuit to then match the correct ratings of the LEDs used.
     
  6. OP
    OP
    logandc99

    logandc99 Dedicated Elf

    Joined:
    Jul 13, 2012
    Messages:
    1,079
    Likes Received:
    5
    Find Me On:
    Wow, thanks for all the quick responses. That makes it nice and clear. I will cut away with peace of mind.

    P.S Sorry I should have said what type they are
    Got the RGB modules from Ray
    http://www.aliexpress.com/item-img/promotion-5050-SMD-RGB-LED-module-DC12V-input-waterproof-20pcs-a-string/423204013.html
     
  7. Bird

    Bird Proud LOR user

    Joined:
    Nov 8, 2011
    Messages:
    1,747
    Likes Received:
    1
    Location:
    Cincinnati, Ohio, USA
    That's one thing you can count on .. usually lots of people watch the posts from the chat room and can reply quickly.
     

Share This Page