LED Fairy Light Modifications

Thread Starter

YoungAnimater35

Joined Jun 9, 2018
5
First time poster, I searched but couldn't quite find what I needed, there's 2 goals I'd like to accomplish.

Goal #1 (priority): I'd like to modify the string lights to where I can run the copper wire to wherever I like, and then have the bulbs hanging down (similar to the icicle christmas lights) so can I just cut the length that I want (about 12 inches) and solder the wire back to the main line?

Goal #2: Would it be possible to "combine" multiple battery boxes into one main box and wire the strands up to run on a single board? I'd like to flip just 1 switch and have them all turn on (6 boxes.)

These are just the simple fairy lights found at Target and TJMaxx, running off 2 AA batteries

Thanks!
Andrew
 

dl324

Joined Mar 30, 2015
16,846
Welcome to AAC!

A picture would be helpful for those of us who have no idea what fairy lights are. Since they're battery operated, is it safe to assume these are LEDs?
 

dl324

Joined Mar 30, 2015
16,846
The answer to both of your questions appears to be yes.

It looks like the LEDs are simply wired in parallel, possibly each having a series resistor; but probably not because they can save a fraction of a cent for each LED in the string. They wouldn't care if any current hogs burned out.

When you combine strings and battery boxes, make sure you observe polarity; always connecting '+" to '+" and '-' to '-'. You can determine LED wire polarity by marking before cutting or by connecting them to a battery box. They should light one way and not the other.

Make sure you insulate your connections.
 

Thread Starter

YoungAnimater35

Joined Jun 9, 2018
5
I've got a volt meter, that works too right? the one that lights up when there's a live wire. As far as insulation, after I solder the wires, would hot glue work, thats what it looks like the used, plus, there appears to be a coating on the wires, would that be an issue as long as the connection is insulated, they'll be outside on a patio, exposed to rain
 

dl324

Joined Mar 30, 2015
16,846
It would work for the battery boxes, but not the LEDs (unless you have a diode check or resistance check that has sufficient voltage).

At 3V, water won't be an issue. Shock is also not as issue as long as you're using AA batteries and don't wire too many in parallel. If you go for a high amperage source, you should fuse it to prevent fire from overloaded batteries.
 

Tonyr1084

Joined Sep 24, 2015
7,853
It's not possible to tell if there's insulation based on your photos. However, logic dictates they must be insulated. Otherwise they'd short together and knock out the unit before you could even get a single light to glow. Depending on how they're insulated, you may have a tough time removing whatever coating there may be. And I'm not even going to guess as to what would be the best way to go about it.

As for your meter causing the LED to glow - yes, when you have a positive current flow the LED will light. Provided you have sufficient current - and not too much current. LED's don't like excess current.

Sounds like you're trying to hang a 12 inch string every - I'll generalize it - 3 feet. You want a main source of power (the positive line) and the main return (the negative line). As with all things electronic - you can wire them however you like - provided you observe polarity. And in the case of LED's, current as well. Hopefully these lights are not that expensive, and you can afford to accidentally burn something out. No, not intentionally, but odds are with your skill level, chances exist you could get something backwards. Heck! I've been messing with this stuff since I was SEVEN years old. And yes, they had electronics way way back then. (over 50 years) And I still get things turned around occasionally. Just repaired a CB radio. Has a protection diode in it. It was shorted, and blew the fuse. When I replaced it - yes - I put it in backwards at first. Was perplexed for several minutes because things should have been working. It wasn't until I looked closer at my work and discovered "I screwed up!" So being new to electronics as you are - pay attention. But yes, you WILL make mistakes along the way. Hopefully not too many and none too costly.
 

dl324

Joined Mar 30, 2015
16,846
im going to tackle this first thing tomorrow
I'd advise you to label polarity as you take things apart and reconnect. Check your work as you go so you can correct any mistakes incrementally.

If the insulation isn't thick enough for wire strippers, you could use a soldering iron to burn it away from the ends of the wires. If you don't solder the new connections, make sure they're mechanically secure before insulating. Heatshrink would be convenient for insulating and it will look nicer than electrical tape.
 
Top