I need some serious help figuring out what I need in a 24V Peltier PSU

I have recently been doing research on Peltier cooling and the like, in pursuit of an upcoming project. I've decided on a 172W Peltier for my GPU, which draws 11.3A ('maximum') at 24V. Supposedly, the 'maximum' draw rating is about 80% of what it will ever actually draw, that being ~9.0 A.

I can always run this Peltier off of my PSU, on the 12V line, for a total of about ~86W, with a power draw of about ~4.5A to ~6A on my 12V line. This is not optimal for me, although I do have an Antec True550W Power Supply.

We need to remember that Peltiers apparantly don't ever operate at their rated peak - so whether I run it on 12V, or 24V, it probably won't be running at a full 86W (12V), or 172W (24V), and won't be drawing a full 11.3A / 6A.

I know very little about the fundamentals of this stuff, and the above information is only what I've gathered through research - I have no means of verifying it, and would really appreciate some more info, if anyone here has any.

Now, onto the gritty stuff that I need help with.

I would like to run this Peltier at its rated 24W, for operation as close to it's maximum 172W capability as possible.

For this, I need a 24V Power Supply unit capable of putting out at least 9A, preferrably about 15A, as a redundant output seems to be highly reccomended. I have found a website: http://www.analyticsystems.com/powersupplies.htm

With some information on 24V Power supply units. However, the models look expensive, and are multi-function. I don't want to pay more money that I need to, and I am also unsure which one I would need to get, the 24V/10A model is the cheapest, but falls below my Peltiers maximum draw specification of 11.3A - which seems to be a big no-no according to what I've been reading.

Could someone please help me figure out what exactly I need in a 24V PSU, and where I can buy it? I have had zero luck looking for retailers with google.

I'm assuming others have faved these probems before, but finding straight forward information on this cooling method has been difficult and unfruitful for me so far - I really, really need some advice .

I've also heard that you can run two cheap 12V PSU's in parallel, for a 24V output or something. I intend to run my power source externally, so this might be an option if it is possible, as space isn't an issue.

Thanks in advance for any info!

I'll try to help as much as I can.

You will actually want to power that 24volt TEC at 19-20 volts. Powering a TEC at 80% at Vmax retains most of the cooling power, while cutting the thermal output (overhead) of the TEC drastically - making it way more efficient and easier on your cooling loop. (A 226 watt TEC at 80% Vmax puts out almost 100 watts less heat while being almost as powerful - in the end you will get much better results because you are handling less heat) So you will want to find a way to adjust the voltage output if you are going to be using a 24V PSU.

From what I have seen people say around here, it seems that dual PSU's in parrallel are not a good solution. Unreliable and shoddy seems to be the overwhelming opinion, but that is just what I see around - I haven't ever really looked into it. If you did, I bet you could find out why exactly it isn't a good idea from someone who's tried it.

I suggest some heavy Ebay research - from what I hear you can get some real good PSU deals on there.

I would also keep a wanted thread running in classifieds as these sorts of things occasionally move through the classifieds, might get yourself a deal there.

You will actually want to power that 24volt TEC at 19-20 volts. Powering a TEC at 80% at Vmax retains most of the cooling power, while cutting the thermal output (overhead) of the TEC drastically - making it way more efficient and easier on your cooling loop. (A 226 watt TEC at 80% Vmax puts out almost 100 watts less heat while being almost as powerful - in the end you will get much better results because you are handling less heat)

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Neat, I didn't know that . I have found a 24V, 20A PSU on eBay that has adjustable output (as low as 22V) - it might be what I want. However, it has some very weird input voltages listed in the sellers specifications posting, and I'm not sure if it can draw input power from a wall socket or not. If it needs som crazy power source, it definetely is no good for me.

Input:

nominal input voltage: 3 x 360-500Vac, 47-63 Hz

input voltage: 3 x 400V

nominal input current:_ 3 x 1.5A

Peak inrush current < 50A

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Whatever that means.

Here is a link to the Power supply I'm talking about (the eBay advertisement):

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=11772&item=3809409341&rd=1

Do you think this will do the trick? If bidding isn't too fierce, I might be able to afford it too

Thanks a lot for the help!

It looks like that power supply is 3 phase, whicl household wiring is one phase. If you'd like, I can explain the difference between 3 phase and one phase, but you probably don't care. Point is: If it's 3 phase, it won't work.

Not to mention it's input voltage is 400+.

check this one out:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=32720&item=3809402149&rd=1&ssPageName=WDVW


As for the current question, YES, 11A is probably more than it draws. BUT, it would be a poor idea to guess it only draws 10A, and buy a 10A power supply, since the powersupply would be rinning at 100% capacity all the time, not to mention you could never run anything else off it.

Ah, I see . Thanks for the information, and all the help you've given me so far Greenman . The one you linked to looks like exactly what I need, would I be able to rig it up to start with the computer though?

I am unfamilier with the wiring involved.

Supposedly, the 'maximum' draw rating is about 80% of what it will ever actually draw, that being ~9.0 A.

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I noticed a typo here, in what I posted. It should be, "The actual power draw will probably only ever be 80% of the 'maximum' Amp rating specified".