[boink]

What is the easiest and cheapest way to wire a 3 pin DC computer connection to AC supply?

The adapter needs to handle 12 V, 8 Watt.

 

[Wasserpest]

You'd need an AC-DC transformer that outputs 12V and 750mA (or more). I keep all my chargers, wallwarts, power supplies etc from devices that are no good no more. So I have a formidable collection of them, and whenever the need arises, I just cut the wires and solder them to whatever needs to be DC powered.

Going to RadioShack and buying one would be easy, but definitely not cheapest. There are discount/surplus shops that sell them online as well, but if you need one the shipping charge takes away the "cheap" part.

For the wiring, soldering the wires together and insulating them works well, if you don't know about that, some small wirenuts should come in handy.

 

[boink]

How would i connect the 3 pin wires to the 2 wires of the transformer? Where does the third wire go?

 

[Wasserpest]

What exactly are you trying to do? Are you talking about a fan? What kind of "3 pin computer connection"?

Most computer peripherals connect via Molex connectors which have four pins: +12, 2x Ground, and +5V. Fans connect to the +12 and Ground, and might have a third wire to control the fan speed. You would connect two fan wires to the transformer, and not use the control wire.

 

[smp]

What is the easiest and cheapest way to wire a 3 pin DC computer connection to AC supply?

The adapter needs to handle 12 V, 8 Watt.

3 pin computer "what"?

If it's a fan then

Red = +12
Black = Grnd
Yellow = Speed sensor

 

[Hoppy]

Use the red and black wires, connecting the red wire to +12 VDC and the black to 0 VDC, which should also be a ground wire. Either cut the yellow wire short and screw a little wire nut over it, or roll it up, with the end having a little wire nut on it.

 

[redman88]

before any more answers are put out please tell us what you are trying to connect to power. so the right answers are given.

 

[boink]

Thanks for the responses. It is for a pc water cooling pump being re-purposed.

 

[smp]

What color are the wires?

What brand cooler is it?

 

[boink]

It is a Danger Den Mag II LE 12 V, 8 W, about 8' head. Wire colors are blue yellow red.

 

[smp]

This cooler is designed to connect to a std motherboard 3 pin fan connector.

http://www.crazypc.com/products/93340.html

I am guessing the color of the wires at the connector (in order) are

Blue, Red, Yellow

see (http://pinouts.ws/cpu-fan-pinout.html or
http://techgage.com/article/danger_den_tdx_block_mag_pump_dd_mag_ii_and_maze_4_gpu_block/4)

Blue = Grnd
Red = +12
Yellow = Speed Sensor

You need to get a 12v dc adapter rated at 2.0 A (this is somewhat hefty but all adapters must be marked) .

Cut the tip off of the adapter and connect the wire with the color tracer (which is usually the +12) to the red and the plain wire to the blue.

If in doubt as to the polarity, use a test meter.

You don't need the yellow

 

[boink]

Thanks for the reply. Will a 12VDC 1 A work?

 

[smp]

Thanks for the reply. Will a 12VDC 1 A work?

I wouldn't try it unless the adapter is "expendable". The pump is rated at 12V 2A. A 1A adapter will run VERY hot or burnout.

 

[boink]

Ahhh i didnt see the 2 A rating and I had a 1 amp laying around. Thanks Steve!

 

[smp]

Been there, done that.......:red_mouth

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