AC water cooling pump

[flclisgreat]

i have a AC water cooling pump. what i want to know is, is there any way to hook the pump up to a 12v DC switch, to make it turn on/off

[Tweaked]

http://www.sidewindercomputers.com/pureswkitv3.html

They don't show one in stock, but that's what you want to find. I had one laying around the house, but I haven't used it in years, not since 12v pumps became more readily availble and more powerful.

But that relay connects to the psu and to the pump, and when the computer is turned on, it brings the pump on. I'm sure the relay is still being manufactured, maybe one of these electronics gurus can steer you towards a place that supplies them. :)

[jonnyGURU]

Awesome little gizmo.

Beats the pants off of converting AC to DC, running it through an automotive grade Bosch 0 332 209 150, VF4 Mini-ISO "fog light" relay and then converting DC back to AC for the pump....

But then again my Eheim pump actually came with a little DC to AC converter that fits in a PCI slot (well, I've since removed the PCB from the bracket and Velcro'd it to the motherboard tray) and allows the pump to run off of my power supply so I only have one AC power cord to plug in.

I wonder if they sell the little AC to DC card by itself....

[madmat]

I can show you how to take a simple 12V (coil voltage) relay and make your own auto turn on for a 120V pump... It doesn't even have to be the expensive Bosch 12V relay, a simple Rat Shack 12V relay will work fine.

[jonnyGURU]

I didn't think you could have AC and DC on the same relay since the relay, if it's one of those "typical" Rat Shack relays, because both circuits use the same ground.

And Bosch relays aren't expensive. You go to a U-pull-it yard and can get a whole handful for a dollar! :D

[Tweaked]

I believe something like this would work as well. Jonny, can you confirm this as being compatible for this usage?

http://cgi.ebay.com/Solid-State-Relay-Crydom-D2425-25Amp-DC-controlled_W0QQitemZ150241981386QQihZ005QQcategory Z36328QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

[jonnyGURU]

Well, it says it supports an AC load and is DC controlled... so that should work. That might be what Matt was talking about.

When I think of cheap-o relays, I think of the four terminal types like you find in cars and, yes, Radio Shack.. but I thought those supported AC or DC. Not both at the same time.

[Super Nade]

If somebody can give me a working circuit, I can whip up a 2 layer PCB for ya in a jiffy. :)

[madmat]

I didn't think you could have AC and DC on the same relay since the relay, if it's one of those "typical" Rat Shack relays, because both circuits use the same ground.

And Bosch relays aren't expensive. You go to a U-pull-it yard and can get a whole handful for a dollar! :D

The relay I bought expressly for the purpose of switching my pump on and off was (is, I never used it) rated for 7-12V DC on the coil and 12-120V DC/AC on the contacts. It's designed for breadboard or PCB use. It was like $5 versus the $10 I paid for a new Bosch relay 10+ years ago.

[jonnyGURU]

Ah... Cool. ok. I hadn't seen those at Rat Shack. I was thinking you were talking about a Radio Shack version of the infamous Bosch relay (which do die quickly by the way. I'll take a junkyard Bosch or Tyco out of a 30 year old VW over any Radio Shack relay any day of the week. :D)

[madmat]

Well, it says it supports an AC load and is DC controlled... so that should work. That might be what Matt was talking about.

When I think of cheap-o relays, I think of the four terminal types like you find in cars and, yes, Radio Shack.. but I thought those supported AC or DC. Not both at the same time.

Actually, a four post relay supports both, two poles are for the coil and the other two are for the load being switched. The same goes for 5 pole types, the three other poles allow for NC or NO use meaning that you can have the relay open or close a circuit upon activation. The ones that share the coil with the relay contacts are either 4 pole NC/NO types or three pole NO type.