pump wiring for morons?

[taoofbean]

Hey all:

I am welcoming myself to your incrdibly educational forums with a question that I did not find the answer to in the search tool. Although lurking with the search tool as my friend for weeks has answered a litany of questions thanks to you all.

How are you all wiring your pump setups? In a perfect world, I would like my pump to come on and then the system power up only after flow has been activated. Given that I am not an Electrical Engineer and do not even own a solder iron, this is not likely very possible. I would like to have the pump start automatically when I power the system.

I understand this means tapping into the power supply line to the motherboard but I would like to do it in the most asthetically simple method possible to power my Eheim 1048 (10 watt drain).

I remember stumbling on a pcmod somewhere in the past that somehow incorporated a flowmeter switch into the tubing so that the system would power on only if the switch was activated by fluid motion.


mr bean

[mfpmax]

my pump is wired as this schematic shows:
http://www.voidyourwarranty.net/revi...rip/index.php3

Have it directly into my PSU

pHaestus also has a nice article:
http://www.procooling.com/articles/h...umps_-_p.shtml

I don't see a need for touching the motherboard...

[nexxo]

Once you wired the pump relay up, you can connect a flowswitch (thread somewhere on this forum) between the green line of your mobo connector. If I'm correct this is the on/off line for the PSU... breaking the connection of this line would switch off the PSU, but I may be wrong here... (anyone out there know for sure?)

The idea is that if the pump fails, the flowswitch goes off and tells the PSU to shut down rightaway. Nice, but best not be de-fragging your HD at the time....

[mfpmax]

Originally posted by nexxo

The idea is that if the pump fails, the flowswitch goes off and tells the PSU to shut down rightaway. Nice, but best not be de-fragging your HD at the time....

Lets see...

Crashed Defrag

Fried CPU

Crashed Defrag

Fried CPU

I'll take Crashed Defrag

Which a crashed Defrag in Win9x isn't bad...not sure about 2K/XP

[taoofbean]

thanks for the input thus far. Cooltechnica sells a relay/switch kit but when I look at the picture for the kit ($18 US) I don't get how this kit takes all the work off your hands. It looks like one would still have to be soldering and drilling holes in their frame to make their kit work.

I am planning on hooking this relay into an Antec True Power ~360 in a Coolermaster case. You can likely understand that after spending so much on this case, the last thing I want is a hacked hole in the back where I have a electric tape laden relay/switch hanging out. I would be willing to try and fit the relay and switch unit in the Antec power supply but I cannot remember how much headroom there is in the supply for me to add a Radioshack relay.

The reason I mention the cooltechnica unit is that the relay component is very small and discreet, something you could easily make room for within the case or in the power supply.

mr bean

[mfpmax]

You're not gonna be able to fit much of anything in an Antec PSU

I built my own relay using the instructions I posted earlier.

I first opened up the PSU and soldered two leads onto the main connection.


I then made a hole in the PSU case so the wires can get out and such...


Then I put a relay into a box and wired it up.



The same can be down with the Swiftech Relay kit. It is simple.

[myv65]

The easiest, most bonehead proof method is merely to plug your PC and pump into the same power strip. Turning on the strip starts the pump, but you must still hit the power switch to fire up the PC.

The one above about the green wire to the mobo is not correct. This is what starts the PC, but depending on your BIOS setup you may find that holding the switch for four seconds turns off the PC. If not, pressing the switch once the PC is running often puts it into standby. In any event, running a flowmeter in series or parallel with the case switch is not what you want.

Relays are very easy to work with and do not require a soldering iron. You will, however, need to strip some wires. The ready-made kits are over priced, IMHO. You can pick up a relay from Radio Shack for <$5. Solid state relays are more reliable and can be had for <$20. The kits use the same sort as the cheap RS ones, yet cost you over $20 with S/H.

For the extra measure of security you do need some more electrical smarts. I'm an ME running a mechanical engineering department, but fortunately I've got a counterpart running the electrical engineering group. I wrote up a spec and he designed a system with a couple of relays, a pressure switch, and a timer circuit. One relay starts the pump and a timer when the system starts. If the pressure switch doesn't pull in prior to the expiration of the timer, the second relay kills power to the PSU. Brutish, but effective.

No need to really start the pump first as the block is capable of handling the heat of the CPU for a few seconds quite easily.

[mfpmax]

Something like that would be better suited for a peltier setup. I'm thinking of doing a delay setup if I build a peltier system.

[taoofbean]

thanks again for more feedback. Looks like I will be building a relay onto my setup and doing some light soldering onto my antec psu. If I could get away with no soldering or cutting, that would be ideal. I am no bonehead but I just don't have the experience doing this to do it perfectly the first time.

Does anyone know the part number for a solid state relay? I looked it up on radio shack and then was presented with about 40 options and I have not a freaking clue which one was for me or which one was solid or not. This all stems from the fact I do not understand clearly the difference between the two types of relay.

mr bean

[Puzzdre]

The usual relay is made with wire coil around a core, and acting as a electromagnet (pulling the contact lever to achieve on/off function). The solid state relay has the same function but it's made of electronic components, and for the better, doesn't have moving parts, ensuring switching without mechanical failure and sparkless.
I would go solid state, although they are a little more expensive...

[taoofbean]

with switch types, why would one want DPDT (Double Pole Double Throw) over a SPST (Single Pole Single Throw) switch in their setup? I thought the switch only served to cut power to the motherboard while maintaining pump, or run both...

I apologize for questions that may seem so trivial to people with a stronger Electronics background. It just is getting confusing to me what the point of having a relay at all is if you are not going to have a switch as well. I mean, Phaestus put together in his article a diagragm and scenario of relay use without a switch but I saw zero advantage of this scenario to just wiring the pump into the power supply feed directly.

Additionally, he drew a molex connector in his diagragm goign from the relay to the power supply, why would you do that instead of just wiring the PSU feeds directly into the relay/switch? Ack...

mr bean

[Puzzdre]

The thing is like this: you want to switch the AC supply for the pump. So if you just plug the pump parallel with the PSU (in the mains) the pump will operate all the time. You need a relay to switch the pump on and off as you turn on/off your computer. The molex is power supply for the relay. The relay coil operates on DC, and if you choose one, find one with 12 V DC rating. So, when you connect the relay supply from the molex (12V), the relay will go on/off along with your computer. On the other pair of connectors on the relay, you connect the live AC mains voltage (pls. insulate all properly), and your pump wires.
So now, when you turn your computer on, the relay gets the 12 V throught molex, activates, and closes the mains/pump circuit, so your pump fires up (not literary, I hope! ). Think of it as two different circuits, 12 V DC, needed to activate the relay, and AC mains circuit, which powers your pump.
It's not really so complicated, but my english is little 'thin' on explaining things like this...
Good luck!!!

[taoofbean]

thank you Puzzdre, very helpful, I did not know the relay itself needed a 12v power supply.

One thing I am still confused regarding, hopefully the last in this regard, is there any advantage to using a relay and no switch compared to just just wiring the pump into the AC line shared by the PSU?

Any source for solid state relays 12V, anyone recommends I would appreciate.

mr bean

[Puzzdre]

If you connect your pump to the line with your psu, the pump will be on all the time, no matter your 'puter is on or off cos' your psu is kinda 'on' all the time, giving that +5V power on voltage to the mobo. So, there's AC mains voltage all the time on the psu, and if you connect the pump there, the pump will be on all the time.

Relay will be an 'automatic' switch for the pump, also, you can put manual switch instead of the relay to turn on/off the pump...But I know that I would forgot to switch it on in 50 % of times...

The ATX psu is always on the mains voltage. Old AT psu's weren't, so you could plug the pump into the monitor outlet on the AT psu and no need for the relay.

On the ATX psu's, the relay will do the good job of powering your pump on and off with the comp. I don't have the relay installed, my pump is on 24/7, no problems for last three months (that long I'm in wc'ing), so if you don't want to hassle with the wires, most of the aquarium pumps are meant to work 24/7, no problem...

Err, MOST of them, so don't get me wrong, it's not 100 % sure...

[p0b0y]

Would this work for the eheim 1250? It says the pump is 110/120V. I dont exactly know if that falls into the 110V category or not.

[JSimmons]

There's always the Criticool pump relay card. It plugs into a spare PCI slot, and you cut the end off your pump power chord and put the colored wires where the instructions specify. It's even got a toggle switch on the card that allows you to run the pump with the computer itself being on.

[Zhentar]

myv- your wrong on the green wire there.

If you've ever tried to run a PSU without plugging it in to a computer you'll notice it doesn't start. The key to getting it going is grounding the green wire on the mobo connector. This pin controls turning the PSU on/off, and it is what your mobo controls with the on off switch. But regardless of what the mobo wants, you break the connection of the green wire and your computer turns off.

What I'd like to do is 2 failsafes- a relay from pump power to the green wire (if thats possible), so the green wire is not grounded while the pump is off, and another connection to the green wire with a flowmeter thingy that I read about somewhere.

My only problem is I don't know how to do this My electrical knowledge is pretty much limited to what I learned in my AP physics class this year, and it was so boring there wasn't much learned.

[taoofbean]

Thanks for resurrecting this thread for me. All of the posts have lead me to greater insight and understanding but I have yet to actually construct my own relay yet.

Do any of you with greater electronic engineering understanding know some specific part numbers from an electronics supplier that I can use for creating this relay/switch? When I go to an electronics webpage and search for solid state relays, I am truely befuddled at a list of 60 options.

Ideally, I want to buy the smallest components possible and then give them to a friend who is an electrical engineer and have him construct the unit for me.

[bigben2k]

I picked up all my parts at AllElectronics.com . They have a special going on now, where shipping is free, using the promotion code SHIPFREE , for orders of $25 or more, until May 15th. (USA, sorry)

Check out pHaestus pump wiring article, for details. What you want, is a SS relay that can handle the current that is being supplied to the pump, so check your pump: if it needs 1 amp, then try to get a relay that can handle more than that, like 2 amps. On the other side, you have to make a design decision: are you going to power the relay from a 12v line, or a 5v line? Try to find something that has a high resistance, because you don't want the relay to draw a lot of power from the PSU.

[Zhentar]

bigben- or you could always get low resistance and hook it up in series with, say, a fan to drop its voltage a bit too.

[bigben2k]

Originally posted by Zhentar
bigben- or you could always get low resistance and hook it up in series with, say, a fan to drop its voltage a bit too.

True. You'd need to make sure that the voltage is split in such a way as to leave enough to activate the (SS) relay.

[taoofbean]

thanks for the feedback bigben.

I have been told I can find solid state (read tiny) relays at allectronics.com that would serve my same purpose. I know the phaestus article well and my only major gripe is that my unit design I wish to be much more compact. The radio shack and allelectronic.com relays I have seen are roughly 1.5-2inch cubes that then have to be mounted into an assembly that makes the entire 'box' at least 3 cubic inches. "Solid state relay" searches on google and various electronic sites have not provided anything that I think matches my ideal.

One site a while back I found was selling a very small pcb with resistor and some form of relay that looked like a small bios chip that made the entire unit 2 square inches with about 1/2 inch height. Something like that could be tucked away inside a power supply.

Size may be a minor quibble with this entire thing for most but for some reason it matters to me not to have a big clunky box in my system. After years of hackneyed computer mods, I may be getting prissy about my projects.

[GenGoku]

i get an error when trying to go to the article

[bigben2k]

Another good source of SS relays is www.mpja.com .

[p0b0y]

Originally posted by p0b0y
Would this work for the eheim 1250? It says the pump is 110/120V. I dont exactly know if that falls into the 110V category or not.

Anybody???