Hey, is it possible to hook up cold cathodes with out plugging them into a computer power supply? The power supply give 12Volts DC. Can't i just use a DC plug that converts 120 V AC to 12V DC from a wall socket, splice the wires and hook them up to the cold cathode inverter? I want to get two 12" blue cathodes and put them behing my desk so they illuminate the wall. Whats the best way to do this without a computer power supply.
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Hooking up Cold Cathodes to a desk. No power Supply.
- Thread starter AlmightyG5
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If i were to do cut the molex connector from the Cold Cathode kit...-
and then take a 12V DC plug and cut that...-
Can i then combine the wires and get the same effect as using the molex connector and plugging it into a power supply in a PC?-
and then take a 12V DC plug and cut that...-
Can i then combine the wires and get the same effect as using the molex connector and plugging it into a power supply in a PC?-
Haha! Brilliant! Well done.AlmightyG5 said:If i were to do cut the molex connector from the Cold Cathode kit...-
and then take a 12V DC plug and cut that...-
Can i then combine the wires and get the same effect as using the molex connector and plugging it into a power supply in a PC?-
iMeowbot said:
Well i'm thinking of getting a AC wall adapter that has 1000mA. The lights run from 200-800mA or something so that should be good right? I have a 12V DC power adapter right now...but it is only 500mA, and i think 1000mA would be safer.
Here's a link to the AC power adapter-http://www.electronix.com/catalog/product_info.php/cPath/265_336/products_id/1561
This should work... right?
i agree with itasor. you can get an el-cheapo power supply from newegg or similar for 15ish bucks, possibly the same in a local store after rebates. it'd be much easier and you could just hide it behind the desk, especially if you get a micro-atx power supply. it'd probably be best to get as low a rating as you can, because really cheap power supplies like that can be 60% or worse efficiency, and at 60% efficiency a 300 watt power supply (v. low end) sucks down 500 watts 
AlmightyG5 said:
If that's 800mA each and you have two, you'll want a 1.6A or larger supply to carry the load. Yeah, I'm being kind of a ninny about this but a beefy enough supply is a heck of a lot cheaper than a fire -- and those little wall transformers do melt down if they're overloaded.
If you don't want the bulk of a PC power supply, you might look into transformers intended for laptops.
iMeowbot said:
I think i'm wrong about that...
I found this article: "Even with both tubes plugged in, the SunBeam kit starts out drawing only about 170mA at 12 volts, versus 270mA or more for newer kits. The SunBeam tubes did this with other inverters, and the SunBeam inverter did this with other tubes, so I thought all of the SunBeam components were weak.
As it turned out, though, the SunBeam kit just started dimmer, and took longer to warm up, than the newer kits. After a few minutes of run time, it made it up to the same brightness as the other kits, and a 550mA current draw."
found here:http://www.dansdata.com/glowthings.htm
And i also found this: http://www.tech-forums.net/showthread.php?s=&threadid=5651
This guy has the same idea as me...And he used a 1000mA power supply with dual cathodes. So i'm thinking 1000mA will be fine.
"Bought 12V 1.0 mA adapter, spliced the yellow and black leads from a female molex to the +/- wires on the adapter, plugged it to the male molex on the cath tubes inverter, and PRESTO!!! - there was light!"
This guy has the same idea as me...And he used a 1000mA power supply with dual cathodes. So i'm thinking 1000mA will be fine.
"Bought 12V 1.0 mA adapter, spliced the yellow and black leads from a female molex to the +/- wires on the adapter, plugged it to the male molex on the cath tubes inverter, and PRESTO!!! - there was light!"
If it works, it works, but I'll make one more stab at playing mother hen here. Would you consider getting a little inline fuse holder from Radio Shack or something and wiring in a 1A fuse? If everything works you're only out two bucks, and if it blows you know it's time to consider a beefier supply.
iMeowbot said:
Are you talking about something like this?-
http://www.radioshack.com/product/index.jsp?productId=2103770&cp=&kw=1a+fuse&parentPage=search
and this-
http://www.radioshack.com/product/index.jsp?productId=2062229&cp=&pg=1&kw=fuse+holder&kwCatId=2032058&parentPage=search
So if the 1000mA power adapter fails...the fuse will break instead of damaging the power supply and/or lights?
The fuse will go if the lights put too heavy a load on the circuit, since 1A is 1000mA. It can save the power supply and you if the lights overload, and it would protect the lamps if a weird surge-like thing makes its way out of the power adapter, but it won't help if something inside the power adapter itself goes wrong (but the house fuse may help you out on that end).AlmightyG5 said:
I was thinking of what someone else posted about just getting a cheap power supply. I found one for $15, but I don't know if it has molex plugs.
Can someone tell me if i can just use this cheap power supply to run my cathodes? Does it have molex connectors?
-http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=935375&Tab=0&NoMapp=0
Can someone tell me if i can just use this cheap power supply to run my cathodes? Does it have molex connectors?
-http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=935375&Tab=0&NoMapp=0
Yes it will, and with modern PC power supplies you typically also need to hook up your own power switch and will have a bunch of extra cables hanging out. Ugly.AlmightyG5 said:
A Tripp-Lite PR-3 should be just about right for what you want to do, it's a nice simple 13.8V supply (13.8 is the nominal 12V you would get from a car) that will nicely handle a sustained 2A without issues. It sells for around $20-25. There are two insulated screw terminals on the front for simple hookup.
iMeowbot said:
Im not worried about the wire clutter because it will be under the one part of my desk that you can't see. You said that i will probaably have to hook up my own power switch.
I found a power supply that in the description says:"features a 4-pin P4 and a 6-pin AUX power connector." Is this the power switch your talking about? Or just the connectors to connect to the power switch.
Here is the link to it:http://www.xoxide.com/orion-xp400-420w-psu.html
Does this power supply come with a power switch?
So will I need a power switch for This Power Suppy?
If so will this work?:http://www.xoxide.com/acrylicpanel.html
The thing is...I have a the power switch set from an old computer...but I lost the power switch... I just have the two LED lights, and a Reset button left...no power button. But i do have the little rectangle connectors (same connectors as the power switch above and pictured below) on the end of the wires of this set. So can i just take a switch i have lying around and put that rectangle plug on it, to plug into the power supply? would that be the same thing as a regular PC power switch.
these are the rectangle plugs I'm talking about. I have these on my old power switch unit that just has two LED's and a reset button. Can i splice them and connect them to a toggle switch or something to make a power switch for the power supply?
If so will this work?:http://www.xoxide.com/acrylicpanel.html
The thing is...I have a the power switch set from an old computer...but I lost the power switch... I just have the two LED lights, and a Reset button left...no power button. But i do have the little rectangle connectors (same connectors as the power switch above and pictured below) on the end of the wires of this set. So can i just take a switch i have lying around and put that rectangle plug on it, to plug into the power supply? would that be the same thing as a regular PC power switch.
these are the rectangle plugs I'm talking about. I have these on my old power switch unit that just has two LED's and a reset button. Can i splice them and connect them to a toggle switch or something to make a power switch for the power supply?
That is a good point. All of the PC's that I've built have their power switch cables attached to the motherboard and the power supply is attached to the motherboard via a 20/24-pin connection as well. How will you turn the supply on without a motherboard?
Two points.
First, wall transformers are not regulated, so they may put out too much voltage and damage the lamp. There is no danger of burning down your house. Get a big enough one, connect up the light, but check the voltage on the leads when it's running. (You could get the type that are sold for cars, they should be designed for more voltage fluctuation, but may need more power and cost more.)
Second, PC power supplies check the load and won't work if there's not sufficient current draw. I used to use an old dead hard drive to test power supplies. I don't know how much power the cold-cathode light draws; you might need to connect up several of them. Edit: Get a used AT-type supply, not an ATX one - the kind with the Big Red Switch on the side.
What I'd suggest is watch for a hamfest in your area, then go there and get a used open-frame 12V regulated supply. You should be able to get it for about a quarter. Hook that up and run all the lights you want.
BTW, why do you want to put cold-cathode lights on your desk?
First, wall transformers are not regulated, so they may put out too much voltage and damage the lamp. There is no danger of burning down your house. Get a big enough one, connect up the light, but check the voltage on the leads when it's running. (You could get the type that are sold for cars, they should be designed for more voltage fluctuation, but may need more power and cost more.)
Second, PC power supplies check the load and won't work if there's not sufficient current draw. I used to use an old dead hard drive to test power supplies. I don't know how much power the cold-cathode light draws; you might need to connect up several of them. Edit: Get a used AT-type supply, not an ATX one - the kind with the Big Red Switch on the side.
What I'd suggest is watch for a hamfest in your area, then go there and get a used open-frame 12V regulated supply. You should be able to get it for about a quarter. Hook that up and run all the lights you want.
BTW, why do you want to put cold-cathode lights on your desk?
cubist said:
The cold cathodes use only like 25 watts so power isn't an issue. Why can't i use ATX? Do I really need a power switch to turn it on...or can i just use the switch that is built on to the power supply? What is a hamfest and a used open frame 12V regulated supply? You are confusing....
And I am not putting the lights on my desk...I'm putting them under with a sound reactive box so they blink to my music.