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What Is Need To Run 10 Miniature Christmas Lights From A Molex?

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July 12, 2009 4:47:52 AM

I just got to case modding as a new interest / hobby. And wanted to know how to go about hooking up 10 Miniature Christmas lights inside my case using a molex. The color of lights if that makes a difference or not is blue. No they are not LEDs.


My power supply is http://microcenter.com/single_product_results.phtml?pro... But they detailed it a little wrong cause I have 6 molex's, 2 Floppy 4-pin Connectors, 2 Sata connectors, and 1x 6pin PCI express connector which they don't list lol and I dunno why but who cares lol.

But any ways. I would like to take my old unused Christmas lights and turn them into a computer case light up system running off or one or a few molex connectors.

If anyone has do this before or know anything or how to do this please tell me cause I would love to know. I try searching Google but didn't get much answers besides how to make a USB power input for those lights but I don't want it to show outside my case to keep it looking nice and cool. Now I am asking. Please give me some insight thanks in advance.
July 12, 2009 6:16:16 AM

Christmas lights are 120v your molex has 12v. So you either have to install a transformer to bring 12v to 120v or change e the bulbs to 12v bulbs. If you can find the bulbs sweet if not it's gonna be to much trouble buy a cold cathode and be done with it.
July 12, 2009 6:26:45 AM

I see. Well that stinks lol Guess I have to go get a few cathodes... Was hopping to do the other way but that information is very helpful thanks.
July 12, 2009 7:53:29 AM

you may be able to find the bulbs if you look around a bit
July 12, 2009 9:06:31 AM

I have some vuage memory that some christmas tree lights are actually a string of low voltage bulbs in series, so the voltage rating of each individual bulb is much lower than 120v, more like 5 - 12v say. You could remove an individual bulb and test it to find out... then either cut the string of lights shorter such that 12v was enough, or re-wire them in paralell.

Sounds like a hassle really to me probably easier just to wrap the lights around in the case, make a hole and plug the lights into a spare mains socket! Another problem I see is a full set of christmas tree lights can get quite warm in a confined space so if you are one of these people that fusses about temperatures endlessly it's probably better to go for something led based...
a c 144 ) Power supply
July 12, 2009 9:55:17 AM

505090 said:
Christmas lights are 120v your molex has 12v. So you either have to install a transformer to bring 12v to 120v or change e the bulbs to 12v bulbs.

Can't transform DC.

One thing you could do is take the 120 volt string of lights, count them, then take 10% of them, rounding upward, and connect them to a molex.
July 12, 2009 12:43:11 PM

Guess I can give that a try. I'm just trying for a cheap way to light up my case without spending money I don't have to. Heat wise I figure if they get to hot I can have a switch or limit the # of bulbs. Cause I was planning to just cut a max of 10 bulbs out or less now that if the heat is to much.

My question is would it hook to the +12 or +5 volt wire? or would it be yellow and black sort of like a fan cable is hooked up to a molex.

All this information is very helpful. I'll try a few bulbs in parallel to see what happens first before adding more. Thank everyone.
July 12, 2009 5:30:52 PM

jsc said:
Can't transform DC.
.


Actually you can, and I don't think light bulbs don't care if it's ac/dc as long as it's the right voltage.
a c 144 ) Power supply
July 12, 2009 6:44:54 PM

Let me elaborate. Transformers do not work on dc.

"I don't think light bulbs don't care if it's ac/dc as long as it's the right voltage. " True.
July 12, 2009 7:25:28 PM

Christmas lights are wired in series, so each bulb receives low voltage (5v I think)
I guess using 10% of the string, as jsc said, connected to a 12 V line from the PSU will work ok.
July 12, 2009 7:38:06 PM

old lights were in series that's why the whole string went out when you had one blown bulb, they are wired different now so we don't have that problem anymore
July 12, 2009 8:00:03 PM

jsc said:
Let me elaborate. Transformers do not work on dc.

"I don't think light bulbs don't care if it's ac/dc as long as it's the right voltage. " True.


Inverters do.
July 12, 2009 8:56:03 PM

505090 said:
old lights were in series that's why the whole string went out when you had one blown bulb, they are wired different now so we don't have that problem anymore


They're not wired "differently" so much as the bulb has what is called a "SHUNT" just below the filament on the filament holders. This shunt is a little wire that connects the two holders together. When the filament breaks or burns out, the current is passed along the shunt allowing the string to stay lit.

The poster that indicated the low voltage of the bulbs by virtue of the series wiring is correct also. When you buy replacement bulbs they are listed by number of bulbs in the string or the voltage, don't remember but somewhere around 2-6 volts.

As for Christmas light maintenance..... when you see burnt out light bulbs, you should replace them as soon as you can... the more bulbs out, the higher the voltage to each remaining bulb. As the voltage rises for more burnt out bulbs, the more bulbs will start to fail....

anyway.....
a b ) Power supply
July 12, 2009 10:51:22 PM

Just a thought:
You could just use the lights as is, if you just pop open a PCI slot on the case and rout the plug end out from that and plug that on to a wall socket (or a surge protector/extension)
July 13, 2009 12:25:03 AM

Use LEDs, you could custom cable to make it look like Christmas lights. (use them in series, check the voltages, 12v will probably be too much for one).
July 13, 2009 12:39:45 AM

You'll need something similar to either an automobile inverter or a direct connection to the main line coming into your PSU from the wall to get 120VAC. A normally open SPST relay with the coil ran by the 12V or 5V will switch the lights on only when you power on the computer (if you do choose to use 120VAC). I'd HIGHLY recommend going with LED lights as the lower voltage is much safer for both you and your computer if you're not very experienced with potentially lethal currents.

No you can't directly run DC through a transformer without it going through a DC to AC inverter or some kind of waveform generator as there will be no collapsing field to generate a current in the secondary coil.

thedraac is 100% correct about how these lights work. I'd first try to just run the lights from your 12V line for the hell of it, if it shorts out your PSU should cut off to prevent any damage. Just in case, an extra PSU to experiment with would be advisable.
July 14, 2009 12:42:40 AM

I just looked up replacement christmas light bulbs and found in my quick limited search that there are 2.5 volt and 5 volt bulbs. I'm sure there are other voltages.

Anyway, with those two voltages in mind you could use the 5 volt bulbs and wire all of them in parallel and use the 5 volt source from the PSU or...

Use the 2.5 volt bulbs and wire 5 at a time in series and connect that to the 12 volt PSU line.

The 2.5 volt bulbs are 200ma, so the 5 would draw 1 amp from the 12 volt line. And the 5 volt bulbs are 150ma, so the 10 bulbs would draw 1.5 amps from the 5 volt line.

Also, the 1 amp draw at 12 volts = 12 watts x 2 (the two sets of 5 bulbs) = 24 watts.
And the 1.5 amp draw at 5 volts = 7.5 watts.

I would try the 5 volt bulbs to use the lower wattage.

Just my suggestion....
July 14, 2009 3:29:16 AM

Alrighty, I'll give that a try. And post my results later on this week when I got enough free time to do so. Thanks for the suggestion.
!