So, as some of you know I have been playing around with some new ideas with water cooling looking for something new worth trying out. One thing that has been bugging me with my planned setup is that there is no easy way for me to start the pumps when the computer is turned off. The pumps for my new system are hooking up to the PSU directly and so I can not simply keep powering them after the computer has been turned off. Also this means that there is no easy way to flip a switch to bleed the system. To address this I figured I could easily hook them up to a secondary PSU. I have extra power supplies that I can use and, I have plenty of space in the computer for them. So here is the plan: Have the two pumps and maybe even some other stuff hook up to the secondary PSU. Have that psu start with the rest of the computer on boot Have the secondary psu power off after X time has passed after the computer turns off Have an option for the secondary psu to be forced on and then toggle the pumps individually on an off (probability using a rocker switch in combination with a safety) The idea is to make it so I can: Have the pumps run for a bit after the system is off and maybe even some cool lite effects that give the impression of the system powering down. Have the ability to turn the pumps on one at a time when I hold a button down so that the system can bleed, ect. I know that I can start the psu by shorting the pins on the atx connector but I want a clean connection. So here is what I am trying to find: Some sort of switch that will short the connection when it detects voltage from a wire that I can connect to the other psu and will keep shorting the wire for X time after the voltage is lost.
just get a small 5v or 12v relay. on one side the primary psu. on the other side green and black wires from the secondary psu atx connector. then just solder another wire from the green/black to a switch on the case for manual turn on.
You can do it just as you describe ZERO. You can have the two psu's connected with a diode, and they each have an individual power switch, so you can turn on just the pump psu by itself, and each pump can have individual control switches if you wish. The good thing about having a diode to connect the two psu's is that when you turn on the pc, you don't have to turn on the pump psu as both psu's will fire up together with the diode installed. A 555 timer circuit can be added with a variable time control knob, so that the pump psu won't turn off straight away but after the set time. You can make the time delay range 1-5 seconds, or 1 second to 5 minutes, or 1-5 minutes, etc whatever you want. I imagine that you would only want the set time delay to occur when the pc has been turned on, not just the pump psu by itself.
No, I would actually want the delay to occur when the first psu powers down (ie the computer turns off) so that the seconds psu keep running. I think delaying the pumps from truing on might be a bad idea for overclocking.
That's actually what i was supposed to mean, i didn't explain myself properly I meant to say that the delay on the pump psu to occur when the pc psu is powering down/pc is turning off, but if you have only turned on the pump psu's for bleeding or whatever, and the pc psu is left off, then when you turn off the pump psu it turns off straight away. I'll probably get a chance later tonight to figure out a circuit. So what sort of delay time range so you think would be good to have on the control knob?
Try applying a jumper to the PS-ON wire and manipulating the power loss setting in bios. You should be able to have a single power supply taking care of your whole system. you should be able to: 1) Make the power supply start without booting the motherboard/bios/windows 2) Make the power supply continue running after windows shuts down As far as making timers and flashing lights, that's up to you. Just keep in mind, the green wire controls whether your psu is on or not no matter what. It's perfectly fine to run the power supply with an inline jumper without booting the motherboard. That's why there should be a bios setting for it. We use this a lot in industrial computing. I'll check if my old nForce has it as well.
This sounds interesting! I haven't ever done that before, so i'd appreciate any other information you have on this
I think the one issue with that is that you would still have your HD,s running and would be sending power to anything else such as your gpus. While it does in theory sound like a cool idea, I think it is actually more limiting as it forces everything to be on and not just the limited number of objects connected to the secondary psu.
As far as time I figure 5-15min should be plenty. I really do not know much about these timer switches and have never built a circuit before so I can not read electrical diagrams. But I can understand anything expressed in logic terms really well.
True, it is a bit funny to have the pc psu on, and all the devices are recieving power, but the pc isn't booting! 5-15 minutes via a knob is easily done. Just to clarify, the idea i had with the time delay is so that the wc still runs for abit after the pc is powered down. If you want the wc psu on for whatever reason while the pc is off, you just hit the wc psu switch and it's on for as long as you want.... unless you want the timer to control how long the wc psu stays on for when the wc psu switch is hit? Maybe you want the wc psu to turn off together with the pc when it's shutdown? I had a quick play last night, and there is one problem with timer... if i want the timer to be triggered when the pc psu turns off, i will need a circuit that gives either a high or low pulse, when a voltage such as 5v or whatver, drops to 0v, which i can use to trigger the timer.
Oh, do not worry your post was exactly what I was trying to say that I wanted to do. I will just add an extra toggle switch to the pumps so i can turn them off and then toggle them when I am filling the system ect.
Modded an old pic i had: I couldn't figure out how to incorporate a 555 timer seamlessly, so i think i've figured out how to seamlessly integrate a transistor based timer. Multiple capacitors can be used in parrallel which simply get added to equal the total capacitance, so you can easily figure out the time, but you'd need way too many capacitors for 15 minutes There's definitely a better way to get 15 minutes using a proper rc circuit... i haven't figured that out, but 15 minutes seems like a really long cool down time for the shutdown timer anyway! I think 30 seconds is definitely long enough, unless you have other stuff in mind? Anyway, here's the untested timer version which i think may work as i've described... possibly : And as for the dummy loads in both of the pics, you might already know but they are needed to avoid running a psu without loading all of the main rails. I've assumed you'd be only using the 12v rails for the pumps and possibly fans, so the 5v & 3.3v would be empty, hence the dummy loads. Each resistor uses a couple of watts each, so 10w or greater spec resistors will run cool, don't get smaller or they can get hot, 10w won't need heatsinking either. If you have some sort of load on the 5v or 3,3v rail other than dummy loads, they need to be at least a few watts total to sufficiently load the rail. ninja edit: And that 10k resistor for the transistor is 1/4w not 25w!
Ah, it is stuff like this that is exactly why I posted this! I had never thought of the need for dummy loads to help protect the psu, I just knew that there was something about leaving one on would be bad for it. Could I just connect like a .5 Farad cap to it... The main psu will be like 1000w anyways. But yea, I will need to look on Google and see if I can find some sort of time circuit. I have attached an image of my plan for the manual start system so that I can power the pumps when the system is off: The switch in the center would be a toggle switch that would probably be able to switch the + and - connections. The other two will be rockers so that the individual pump will only power up when the switch is pressed.
Sorry, but your wiring diagram doesn't make sense Im guessing that maybe you want to be able to flip posistive & negative so that the pumps can go in reverse? If so, are you sure your pumps support that? I think many and possibly all pumps are unidirection, or at least most effecient in one direction than the other. I just thought of an idea, to add an rc circuit to my design above, giving a wide variety of delay time... I'll probably get it done later and put it up. I'll include switches for two pumps and a power reversing switch.
Back in version 2, i estimated the delay time to be about 10 seconds... i now think that may be more like 10 minutes I've modded the timing circuit by adding a small variable resistor, any small one will do fine, and there's a table with some different combinations. My times are estimations and actual times may be a little shorter... i'm not even 100% sure on the timing circuit by the way, but it's cheap and there's definitely no risk at all of damaging anything, so you can experiment and let me know how it goes Note the pump switches and the two warning leds. The 220 ohm resistor will run a 1.8v led at 15ma, you can calculate what resistor you'll need here I also labeled the 1000uf timing cap as 16v, which is the minimum rating you will need to use for any timing cap, since it will be charging at 12v. And the reversing switch version:
Ah very nice thanks for the help! On my pic I was showing a switch that would cut off the power to both pumps when it was switched over to complete the circuit for the psu to turn on. This way if I turned on the psu manually it would cut the power to the pumps. I would then power the pumps using a buypass switch that would be a rocker so that the pump would only run when I press it down. This way I can run the pumps individually with perfect control while the system is off.
I'd imagine this could work nicely if you can jump the 5 volts back up to 12. http://www.svc.com/nx-prolong.html Edit: Unless you really want two PSU's.
