Instructables

Is there a way to power rope lights portably ?

I have these rope lights I'm using to make a whiplash costume. Obviously, I'm going to use them as the whips. But I need a way to power them with a battery or something. I've tried 12 volt batteries (which work with regular Christmas lights) but no luck. I think its because I need more current. Does anyone have a suggestion?

VIRON1 year ago
I am experimenting with a simple circuit which I might make an instructable but I have a quick answer.
I recommend using a whole string of LED rope lights with a power inverter which is made to convert 12 volt car socket into an AC outlet. plug the rope into the outlet and connect a gel cell to the 12 volt plug. I hope you know the polarity; a cigarette lighter plug is + at the tip. I recommend a 50 watt power inverter that is cheap. Don't forget to disconnect the battery to turn off the rope light because the battery will go dead from the inverter if you just unplug the rope. You can use any rope light but light bulbs drain the battery quicker.
Some inverters might not like to power LEDs (especially if they were made in the 1900s) if they are simple oscillators that get confused by half wave rectification.
drmetal271 year ago
I have wired 12 leds in my truck as the dome light and it was brighter than the old light bulb that they tell you is the only one you can put in there , and it uses 99% less power, i tested it my self with a multi meter, old light uses about 2.5 amps and the new homemade light uses .05 amps, 99% might be a little off but it is a lot brighter, and it won't kill battery if you didn't close you're door all the way, i looked after a couple of days and my dome light was still on, now if i did that with the old light I would not be able to crank the motor because the battery would be dead, but with the new 12 led light it can stay on for weeks and not kill the battery.
drmetal271 year ago
another type of Christmas lights are 12 volt lights which might be 10 per set, and L.E.D. (light emitting diode) is not an incandescent bulb, it is normally for dc only but AC won't hurt it as long as you do it right, white and blue leds are 3.5 volts but you need a resistor or you will burn them out before you can see what they look like, 220 ohm 1/4 watt resistor is good for 3 leds in series on a 12 volt battery. this can be used for any 12 volt battery from one of those little ones from the photo center at Walmart to car batteries and above as long as it's a 12 VOLTS battery. you have to get the polarity right on leds or they won't work, you can always find leds and resistors on eBay on in radio shack. you can also find leds in the dollar tree.
drmetal271 year ago
you already know that it's possible, but either nobody want's to give up there tech repair secrets or you haven't asked the right person yet. i have seen 3 types of Christmas lights, but there are more, if it has 50 lights its 3.5 volts for each light, you can cut 3 or 4 lights in series for 12 volts, 3 being brighter, 100 set is two sets of 50.
You'll have to work out how much power the lights take, and what voltage they need.
Adum24 (author)  steveastrouk4 years ago
They need 120 because they get plugged in, but a 12 volt battery should work because I used it for regular Christmas lights. For some reason it doesn't though.
So do you need a wall-wart to run them ?
Adum24 (author)  steveastrouk4 years ago
Yeah, but I need a way to run them without a wall-wart. Like with a battery.
What does the wallwart do ? Does it just provide power, or does it do special light effects ?
Adum24 (author)  steveastrouk4 years ago
Oh, sry, I thought by wall wart you meant outlet. I get those two confused. I need a way to run it with a battery or something instead of plugging it in. So, actually, it does not have a wall wart.
Right, in that case these aren't the best lights for what you want. You COULD carry a mains inverter, but you'd be much better with LED lights.
Adum24 (author)  steveastrouk4 years ago
Alright thnx for the help!
Adum24 (author)  steveastrouk4 years ago
Alright, thnx for the help!
Re-design4 years ago
If they run on 120 volts then that's what you'll have to provide unless you rewire them.

That's just a fact of life.  It might work on 120 volts dc, without knowing the lights I can't tell you.
To get portable 120 volts, you'll need an inverter... and frankly, I'm not sure I want someone generating that high a voltage in costuming. Especially given that if you're going to use them as whips they're likely to get damaged.
Adum24 (author)  orksecurity4 years ago
Alright, thnx everybody. I've decided to buy a 12 volt rope light so I can use a 12 volt battery. I might possibly use a pre-hooked-up battery powered rope light. I'll return the other ones