Check out some similar questions!

akriger0072 · Oct 22, 2007, 03:48 PM

Hello. I just purchased 4 SPST LED rocker switches the other day. I am using a computer power supply to power the switches by paperclipping the 3rd (black-ground wire) and 4th (green-PS on) wires. My problem is that the LED does not light because (I am told) I need a white neutral wire to connect to the 3rd prong on the switch. My power supply does not have a neutral wire so what do I do? Where do I get one? How can I use my rocker switch? I need a neutral wire!!

Stratmando · Oct 22, 2007, 04:14 PM

If it is LED and OK for 120 volts(has dropping resistor), then the correct way would be to
Open power supply, solder white wire to input from Power Supply Plug White Wire. Does not have to be large wire, but should be rated for the voltage. The small white wire on ceiling fans,( A piece leftover from a fan that came with 4 foot of wire, but you only needed 8 ", is perfect. You should not use the case or metal. Use Wire Tie to secure wire.

akriger0072 · Oct 22, 2007, 07:04 PM

Thanks for the advice but that seems hard and dangerous, is there any other way, I'm not sure I know exactly you are suggesting me to connect the neutral wire to. Thanks.

Stratmando · Oct 22, 2007, 07:49 PM

What are the colors that went to the old switch? 4 Wires?
The neutral would be the white wire inside power supply, directly in from the 3 prong plug.
It is safe with power off. When you power up, it is at ground potential, it won't shock, but can short to live parts, connect and secure.

labman · Oct 22, 2007, 08:12 PM

I don't recognize your wire colors. What are you switching, the 12 volt DC output of the power supply? It isn't going to work if you are using LED switches rated for 120 volts. They have resistors built into them that are too big. You need to use the right voltage switches, change the resistors, or wire up separate LED's and resistors.

Stratmando · Oct 23, 2007, 05:47 AM

I agree the colors are strange, Black is usually hot, green usuall ground.
Don't have power supply in front of me, but thought they had colors like Blue, white, black and brown. With the neutral switched also?
Hopefully the switch is an indicating switch rated for 120 volts?
Be sure you understand switching, you could accidentally switch hot to neutral.
Paperclipped black and green?
If the switch has 4 contacts, 2 for the switch and 2 for indicator, you will need a neutral.
Without a neutral, you could parallel led with switch. Then Indicator would be on when computer is off? You could find on off switch in the dark?

akriger0072 · Oct 23, 2007, 06:29 PM

Ok. The black (ground wire) and green(PS-on) wires I referred to are on the power supply (I am trying to clear up any confusion with the wires ). As I mentioned it is a computer power supply that I am using to power the rocker switches and I placed a paper clip onto these 2 wires to trick the power supply to come on and be able to use it without connecting the power supply to a computer motherboard. These 2 wires (black and green) are a part of the power supply's 20 pin connector that would connect to a computer's motherboard. I hope this makes sense. A lot of people use this power supply trick to power a water-cooling system and test for leaks (if water leaked into a computer=disaster!) Ok the wires I am using are a part of the power supply's molex connector yellow (+5V), red (+12V) and 2 black (ground wires) and that is what I was using to power the switches but it states on the prong labeled 3 that I need a neutral wire (to power the LED) without it I just have a boring switch. So I will try and connect the white wire to the power supply is there anywhere else I can get a white wire other than a ceiling fan? I do not know that much about electricity, neither have I ever wired anything; I am a computer repair guy. Anyway thanks for everyone's help. Anyone else have any suggestions/comments? Thanks!

labman · Oct 23, 2007, 06:56 PM

You still haven't said if the switch is for 120 volts. If so, even connecting to the neutral isn't going to work. Such a switch would have 3 contacts, power in, power out, and a return, the neutral. Connect an LED and a resistor from the power out and neutral, and the LED will light when the power is switched on.

I guess I have never gotten beyond the 4 wire connectors for disk drives and such, an didn't realize there was a 20 pin connector to the mother board. I have 2 computers open right now. I have been contemplating a mother board swap.

akriger0072 · Oct 23, 2007, 07:18 PM

The switch says 100-125V

labman · Oct 23, 2007, 07:47 PM

It won't work unless you take it apart and replace the resistors in it. Not everything is meant to be taken apart and modified, or worth while.

ballengerb1 · Oct 23, 2007, 08:03 PM

AK, what country are you in? This might explain why these colors are unusual. Kevin will read this on Wed. so try to answeer my question by then.

Stratmando · Oct 24, 2007, 06:44 AM

Some power supply switches that go to front panel, with 4 wires, hot and neutral in, and hot and neutral out. Some are indicating.
Unplug switch and chec voltage between each pair combination.
Black and green, black and brown? Brown and green. If you get 120 volts between a pair,
Then determine which of those 2 are hotby using metal chassis as a reference.
If that is this other switch I'm thinking of, it will have a hot in, switched out, and needs a neutral for the indicator. Neutral was center on those. Verify with paperwork, or a meter.