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relay to make 110v pump turn on whith computer

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fatshlink

Member
Joined
Sep 18, 2001
Location
RIGHT BEHIND YOU!!!
people that have water cooling whith a 110v pump. I have herd people talking about a relay that turns the pump on when you flip on your computer. could someone tell me how to build one of these???
 
(warning) unplug your pump and system before you do this!!!
You have been warned!.

(warning) am tried and sleepy so you should ask around for help the first time.


Ok disclaimer over.

I mounted mine inside my PS unit. You should be able to find a Relay at Radio Shack that can take the current of your pump.

Tell the sales person you need a 12 volt relay that is rated at your pump current x 2 (safety you don't want the contacts fail on inrush)
unless you are running a very large pump they should have one that will work. The current rating should be on the pump.

The relay has a coil when 12 Volts is applied the coil will close on set of contacts on the relay this is the set of contacts you need to use to break one side of the 110 volts to you pump. (These are called normally open) or N.O.

Although this is not something hard to do you should get some help from someone that knows about electronics. There are things to watch out for and 110 Volts can kill you and your system if it arcs over.

I will assume you have a 110 volt plug on your pump. You will need to remove the plug you should have a white black and green wire. The white wire is common the black is hot and the green is ground. (In most cases)

Now if you want to have the pump so it can unplug from the PS then you need to place a connector in line so you can unplug the pump for service and such. Keep the black wire to black white to white and green to green. Be sure the connector is rated for 110 Volts at the current you need.

Now open you PS (This will void any warranty!) Now the connector that the power cord plugs into will have 110 Volts and ground. On most units that I have seen you will have your white black and green wires.

Next you want to mount your relay. Most relays that will handle these pumps will fit inside the PS case. I mounted mine inside with some Silicon cement.

Once this has dried you need to solder the white wire onto the white wire on the PS connector. The black wire from the black wire on the PS to one side of the relay N.O. contacts. Now you solder the black wire for the pump to the other contact on the relay. And solder the green wire to the green wire of the PS connector.

Now you have the 110 Volts part in place double check all the connections.

Now you have to find 12 Volts in the PS. I find it is easy to pick up 12 volts from the 12 volts that supplies the fan here you connect red or +12 volts to the + side of the relay coil and the - or gnd side of the fan output to the - or gnd side of the relay.

Now to test. You can find this around on the net might to to check me on this its late and all. Connect a small wire from the green wire on the ATX power connector to a black wire this should start the PS and your pump.

Good luck and get some help from someone that knows a little about electronics.


Best of luck and be very careful
 
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