How to wire an illuminated switch?

GrenadeKing

Sr Member
Okay, so I have a small project that requires the use of an illuminated switch.
It has 3 terminals. Ground, Load, and Power. I'm running off of a 12 volt lantern battery.
I currently have it wired in series through the + path of my circuit. And, there in lies the problem. I need the full current of the battery to come out on the other side, but the way I have it wired drops the current to almost nill.
Thing is, if I wire it any other way, the light wont light.
I can run to the Load terminal, and get full current through the switch, but I have no light. To get light, I have to run it through the Power terminal, and I dont get enough current.
I'm stumped on how to make it light up and get full current on the other end.

Any electrical experts out there, or just plain anybody, that knows, your help would be greatly appreciated. :cool
 
Hi, you mentioned that you are working with 12v DC.
First, the light source in your switch would have to work with 12V dc.
Then, without seeing the switch, I would imagine that the light is wired internally and would require 12v to illuminate. So, if the pos. and neg. power was put on the switch as shown, then the internal light should turn on and off by the switch, then all you would have to do is add your "load/circuit" to the terminal marked LOAD and wire the other leg of your circuit to GROUND (as shown in the picture). Hope this is of some use....if this doesn't work, maybe give a bit more information :)




switchxt5.jpg
 
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i used to use these in the truck i had i wired them up to light up when i turned them on.

what the problem is, is you have to have 2 seperate powers to it.

i know, you say, what?

heres what i mean. you have to have 12 volts just to run the switches illumination when on.

the other power i refer to, is the power itself to whatever it is your switching on. thats the only way these kinda switches work.

1 hot for the switch itsdelf, and the other hot, for item its switching on and off.

i dont know for sure if the switch your talking about is similar, but thats the only way they worked when i hooked up stuff on my truck, horns, ETC..............
 
Switch is a lighted SPST rocker switch rated for 30amps at 12 volts.

What I'm trying to do, it wire the switch into the positive side of my circuit. It's pretty much a "fire" switch. I have a wire from the positive terminal of the 12 volt battery to the Power tab of the switch. And then from the Ground tab to my "bang device" and from that back to the battery. This lights up the switch when I switch it. However, the "bang device" doesn't get enough current to do anything this way. If I run the positive to the Load tab, I get the current I need but no light.
I need to find a way to get light and current.

I believe Lan-Ed-Tul is probably right. Which, I was afraid of. :unsure

So now I suppose I'd be looking for away to make this work on just 1 battery. Or at least, one 12 volt battery. Any smaller ones would be fine I think.
 
well, you can run 2 wires off the battery to the switch as i mentioned. one lead for switch, for the item, and other lead for lighting the rocker. thats how i run them in my truck for accesories.

it just sounds to me, from what you describe, that your pulling switch and item, together off one power lead, and thus you wont get the full current to the one.

so try running another wire from the battery as i described, and just see if it will work right then.
 
well, you can run 2 wires off the battery to the switch as i mentioned. one lead for switch, for the item, and other lead for lighting the rocker. thats how i run them in my truck for accesories.

it just sounds to me, from what you describe, that your pulling switch and item, together off one power lead, and thus you wont get the full current to the one.

so try running another wire from the battery as i described, and just see if it will work right then.

Or just short the power and load at the switch...
 
It sounds like you wired the "internal light" in SERIES with your load, it needs to be across the load (parallel). You only need a single power source to operate the internal light and your load.
See the diagram attached:

switch2jh0.jpg



Both the load and the light will receive the 12v from the battery.
 
Well, running 2 lines from the power terminal fixed the problem, but left me with another problem. I have both light and current, however my "bang device" is still inoperative.

Basicaly, the device is a piece of wire that heats up when I use it to short the 12 volt battery. With the battery alone, it glows just fine and dandy. With my switch it does nothing. It doesn't even get hot.
I'm just not understanding it. I have more current than my multimeter can read, just like with the battery alone, and my light lights up, but I get no action. :confused
 
I get no action either. :lol

1. Connect the battery +ve to the power terminal
2. Connect the battery +ve to the nichrome wire (then to a suitably small resistor/potentiometer) then to the load terminal
3. Connect the battery -ve to the ground terminal
 
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I don't really see how a resistor would help, nor do I know which to use.

I tried it without one, and I still got nothing, so... :confused
 
Well, running 2 lines from the power terminal fixed the problem, but left me with another problem. I have both light and current, however my "bang device" is still inoperative.

Basicaly, the device is a piece of wire that heats up when I use it to short the 12 volt battery. With the battery alone, it glows just fine and dandy. With my switch it does nothing. It doesn't even get hot.
I'm just not understanding it. I have more current than my multimeter can read, just like with the battery alone, and my light lights up, but I get no action. :confused


well i may have been partially right then.

i know that is how i had to run the switches like that, in my truck in the overhead console. i dont get tho, why its not heating up the wire, for you.
 
GrenadeKing: The optional resistor/potentiometer would reduce the current through the wire and thus control its temperature.

Hmmm, are you sure that setup didn't work? (Battery +ve to wire to load terminal) plus (ground terminal to battery -ve) gave you ample current but no light, as before, but adding (battery +ve to power terminal) didn't also light the switch?
 
Something to concider- If the light source in the switch is an LED with a dropping resitor for current reduction at 12Vdc and your LOAD is a wire shorting accross the battery (and the internal LED in the switch), then it's very possible that the resistance of the wire is much lower and is "shorting out" the LED, causing it not to illuminate but still allowing the wire to heat up. You may have to go with an external incandecent light connected to the switches normally open contact.

Added: If you still want to use the illuminated switch, then you can use that switch to energize a 12vdc relay with contacts able to handle the high currents of the wire. The coil on the relay would have a much higher resistance and it's contacts would do all the work to heat the wire.
 
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GrenadeKing: The optional resistor/potentiometer would reduce the current through the wire and thus control its temperature.

Hmmm, are you sure that setup didn't work? (Battery +ve to wire to load terminal) plus (ground terminal to battery -ve) gave you ample current but no light, as before, but adding (battery +ve to power terminal) didn't also light the switch?

Yeah, I guess I was a little plastered when I tried what you suggested. :lol
That worked like a charm actualy... until I turned the switch "on". :wacko

I guess the battery just can't supply both at the same time.
With the switch off, I get wire frying, but with it on, I get nothing.
 
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