Splicing Mini Christmas lights together

[hutchijw]

Hello Everyone.

For simplicty, I'm going to use "round numbers"

If I have a 100 count set of mini lights but for my display I need, lets say, 120 total (all on one string). Can I cut the 100 count lights in the middle, and add(splice in) the 20 lights I cut from the other set of lights giving me a total of 120 lights on the one strand?


My reason for asking is becuase the local buck or two store actually has christmas lights in there right now. The problem is that the length is only 12' and i need them to be 15' for my application. The lights do not have a female receiving plug on the end so I cant plug another set into the end of the first set. So I want to add another 20 or so to the first set.

[P. Short]

No, generally you cannot splice them together in that manner.

The bulbs in the mini-strings are all fairly low voltage (2.5V and 3.5V are common), connected in series-parallel combinations. For the 2.5V bulbs you need to have 50 of them in series across the AC line for proper operation (too many, and they are dim, too few, and they burn out very, very quickly). So if you have 2.5V bulbs, they must be connected in multiples of 50 (each substring has 50 bulbs in series, and the sub-strings are wired in parallel across the AC line). If you have 3.5V bulbs, they are connected in multiples of 35 (usually).

--

Phil

[Macrosill]

I just happen to be working on a How To about cutting sets of Mini Lights.

Keep an eye on the wiki for the article.

[jstlucas]

I just happen to be working on a How To about cutting sets of Mini Lights.
Keep an eye on the wiki for the article.

Ooh, ooh, this is something I need to know how to do.

[0RESET0]

I want to do something similar but I know I have to have them in multiples of 50. If I want to permanently join 3 strings of 100 lights, do I just cut off the plugs and join the ends? Does it matter which wire I connect to which? I would also like to do the same thing with my commercial mini lights. I can connect 6 strings of 100 together on those and they always go together. I would like to put them together permanently so that I don't have to worry about them coming un plugged on my 30 foot pine.

TIA

[Macrosill]

Sean,
Go ahead and solder them together. The polarity does not really matter.

[jmelvin]

Well I went to wally-world today to grab some icicle lights to replace some sets that were to faded from the sun (Florida). All my current ones are 9' long with 150 lights. All I could find was 300 count sets at 18', no brain-er cut them half. But then I got to thinking :shock: there are 6 sections per set, divide them all up and have more control. Smoother chases. Maybe you could add it to your wiki how to.

[Macrosill]

How about you take some pics when you do yours and add it to the wiki.

I need everyones help in making this the best place to be!

[poppylites]

Merry Christmas!!!
Does this 50 light rule still hold for these new LED lites?
I have only 2 15W outside outlets which was really limiting with the old lites but with these new LED lites I can go a little crazy now.
But it would be nice if I could cut & splice these new LED lites to length.

[Traneman]

How do you know what voltage bulbs you have?
No, generally you cannot splice them together in that manner.

The bulbs in the mini-strings are all fairly low voltage (2.5V and 3.5V are common), connected in series-parallel combinations. For the 2.5V bulbs you need to have 50 of them in series across the AC line for proper operation (too many, and they are dim, too few, and they burn out very, very quickly). So if you have 2.5V bulbs, they must be connected in multiples of 50 (each substring has 50 bulbs in series, and the sub-strings are wired in parallel across the AC line). If you have 3.5V bulbs, they are connected in multiples of 35 (usually).

--

Phil

[poppylites]

Paperwork says 50 microlights, 2 volt, .04watt, .02 amp, 12.7ft length.

[djulien]

Does this 50 light rule still hold for these new LED lites?
I have only 2 15W outside outlets which was really limiting with the old lites but with these new LED lites I can go a little crazy now.
But it would be nice if I could cut & splice these new LED lites to length.

LED strings where all the LEDs turn on/off at the same time tend to have a resistor in series with the LEDs, often embedded within the plug at either end of the string. You can remove or splice more LEDs into the string (up to the max number that can be in series for your voltage supply) if you use the same type of LED and if you adjust the size of the resistor to match the number of LEDs.

There are "LED calculator" tools available to help with those calculations - for example:
http://doityourselfchristmas.com/forums/showthread.php?11830-LED-Calculator

You probably want to try it on one string first to make sure it will work before getting too many of the strings.

don