12V pump relay

[freshy98]

I bought a Swiftech MCP600 12V pump. It is now flying in from the USA to The Netherlands :-)

My setup will be kinda large having two heatercores, a Cascade waterblock and a D-TEK GPU waterblock, so I want the pump to first generate a nice waterflow and to get the temps down for about 30 seconds before the rest of the system get's turned on.

I know there are relay boards and stuff for 120V/230V, but I need something for 12V since the pump is connected using a molex connector to the PSU.

What I was basically thinking on is the way Chillcontrol from Vapochill works.
This means that when I power up the system it must not start the motherboard, but wait for 30 seconds using a relay switch. During that time the rest of the the devices not connected to the motherboard are working. This means my fan´s :-)

Does anyone know a schematic for this, or is there something to buy like this?
Please let me know!

Thanks very much in advance.

Even nicer would be for the schematic to let the pump runs for anothe 30 seconds after the system has been shut down so the the heat genereated by the CPU and GPU can get out. There is allways heat after the system has been shutdown... But that would require for the PSU to be on to for another 30 seconds. I think this could be done using a circuit though. Same as start up, but then the other way around.

[SK8]

i would say just run another psu and the pump picksup pretty fast so i dunno if i would spend the dough for it

[freshy98]

But that is the easy trick, plus I need an extra PSU which will use power too! I have a 550W Antec True Power, so I will not add a second PSU just for the pump.

[Graystar]

If your system is turned off, then all of it is at room temperature. You can't cool it any further, no matter how long you run the pump and fans. When you turn the computer on, the pump immediately gets power and the water-cooling system starts performing its job immediately. There is no delay, so there’s no reason to start it up first.

It is my own personal assessment that such a time delay would provide no benefit at all. I would recommend skipping it.

[eXCeSS]

It might even worsen your temps, because if you have the pump running, the heat from the pump will get transferred to the water, even before the computer is on.

I'd say skip it.

[freshy98]

well, I'm not going to make a circuit untill I think it is nescaserry. So I will first let it run without any relay.

Thanks for the input!

[cherryp00t]

it'll be fine. you dont need a relay for that system because water can hold alot of heat.. once the computer is on so is the pump so there is no worries

[rogerdugans]

If you want to check the theory out, try setting up the pump, blocks and rad before installing in the computer.
Measure water temp and then let it run for an hour.
Measure water temp again- it WILL be hotter!

I do realize that you wanted to run the fans as well, and then would cure the pump heat issue but it would also add quite a bit of complexity, work and take up space in the case- and for no benefit:

Turn the system on after it has been off a while- check temps in bios then boot to the operating system and check: you'll see that it doesn't get too hot too fast. Then get the cpu running at 100% load and check temps: it will be hotter!

Reboot and check temps in bios: I bet they will be closer to the cold start-up temp than they are to load temp...

Point being that when you take away the creation of heat (cpu load or just being on at all) the components do cool down rapidly.

No worries. :)

[freshy98]

sorry for the very late reply people, must have missed a notification mail somewhere.

I wanted to thank you all for the great input! Trying the setup out myself would take too much time if it allready has been tested.

This week I will hopefully receive my Swiftech MCP-600 pump and then I will order the fan's and some other stuff and I will start building it all together :-)
Only problem is I need to mod a AT PSU so I can test the water cycle without powering the entire PC. (the Swiftech pump is a 12V pump with a molex connector).