Power sloution for two 172W pletiers for less than $200??

[Petrus]

I've done alot of searching and I still haven't found what I'm looking for. This is my problem: I want to power two 172W DRIFT-0.8 peltiers (11.3A 24V) @ 20+V. The power supply should fit inside my Addtronics 7896A case, and should not kill everything else with EMI (or whatever it's called). Does anybody know of a powersupply manufacturer that might have a suitable unit. Even better if you know of a company, preferably within EU, that sell them. I'm prepared to spend $200, and as a last resort perhaps as much as $250.

Please help me!

[mASO]

everything u need is on this site! open your eyes! http://www.procooling.com/articles/h...chnology.shtml

It's as easy as that! i'm using this scheme right now! works perfectly. no more problems with power! i am using 3 psu's in parallel.

[Petrus]

Thank you mASO for your reply! I appretiate it! Unfortunally I have allready read that article. Since there is only room for two more AT/ATX powersupplies in my case (with some minor modifications that is), that means I have to get hold of two PSUs that can deliver 11.5A @ 12V. I'm not quite up to speed on PC PSU prices but if I'm not mistaken these aren't exactly cheap, right?? So I figured, if I'm going to spend $$$ then I might just as well buy a smaller dedicated 20-24V PSU that will deliver atleast 23A. A cleaner sollution in my oppinion.

Is it possible to run the peltiers in series on a 40V PSU that delivers 11.5A?? If so, that could be an option too.

[hielko]

Running peltiers (electrical) in series is possible.

I've got two 24V @ 15A PSU's for $35 a piece at E-bay. Very cheap, at least for people living in the USA.

I don't have them yet, but Phreenet send them to me a week ago, so they could arrive any day now . (I'm living in the Netherlans, and he was kind enough to help me getting those to me)

[Kevin]

Check this page out: http://www.peaktopeakpower.com/catal...nwell-001.html
I'm not sure if any are powerful enough to power TWO 172w pelts, but maybe. Let me know .
-Kev

[Petrus]

Kevin: Unfortunally they are not powerfull enough to power two 172W . Not even the SP-500-24 wich delivers 20A @ 24V is enough. But I know that MeanWell has a 600W unit that puts out 25A @ 24V, but it also has some extra (unnecessary) functions that probably cost extra. Besides the 500W unit listed above costs $283! I don't even want to know how much the 600W unit is!

Thanx for the link tough, now I have some pointers to how much they are. Keep 'em comming!

Hielkos post got me thinking, I have been so focused on one medium sized PSU, but now I'm thinking about getting two less powerfull and slimmer units and mounting them on top of each other (if possible due to placement of wenting holes on the PSUs). Two S-350-24 (14.6A @ 24V) would do the trick, and they cost about $105 each (probably a bit more expensive here in Sweden though). Dimmensions are 230 x 115 x 50 mm, so they will both easily fit inside my case. Ok, now I have a backup plan if all else fails. One "minor" problem still remains, from where do I get these from within the European Union???

Any other ideas, manufacturers, retailers and/or links??? It's nice to some to choose from! And thanks again to all that have answered so far!!!

[Petrus]

Originally posted by hielko:
Running peltiers (electrical) in series is possible.

I've got two 24V @ 15A PSU's for $35 a piece at E-bay.

Do you have the make and model of these units, and their dimmensions? Mayby I too can find them for a resonable price. Are they desktop or "built-in" units?

[hielko]

I do have their demensions and specs etc. They are Power-One PFC375-1024 PSU's. The are sized 23x13x6cm or something close.

I don't think you will find them on ebay, you will have to be luckey. But if you search on 24V on e-bay you will find most 24V PSU's for sale .

[Petrus]

Thanks Hielko! I didn't think I would find 'em on e-bay , but perhaps someplace else at a resonable cost.

As it is right now I only know of a few PSU manufacturers that have units suitable for this application, and I (an probably other in the same situation) would very much appretiate it if we get more suggestions here in this thread. It doesn't matter if you don't know for sure, I can check 'em up my self as long as I have a place to start.
I will post a list on suitable PSUs when I have a more comprehensible list. So keep 'em comming!

[hielko]

All big (industrial) PSU manufacturers have some high wattage 24V PSU's. Lambda, Power-One, Meanwell, HP, etc.

[thebigNil]

will this work http://www.allelectronics.com/cgi-bi...m=PS-550&type=

it was on the procooling main page and I thought it was a good idea to bookmark something like that

[Petrus]

thebigNil: Nope, unfortunally it does not. Although it is a 550W PSU, it is also a tripple output unit (3.3V,5V,12V) and "only" puts out 12A @ 12V. That would mean you'd have to use four of these to get 2 x 12A @ 24V !!! Had it been a singe output 20-24V 550W unit it would have done the trick. Thanx for your reply though!

[thebigNil]

oh now that I look at your post closer I see that you were wanting 12A@24v. sorry my mistake :} .

[mkosem]

SCN-600 is a model on the site kevin linked to that will power both pelts!

--Matt

[jastrckl]

You might want to look into using a pair of car battery chargers in series. Make sure the amperage on each supply is higher than the amperage of the pelt though.

[Overlag]

The Samlex Power Supply Model SEC-1223 13.8V can be Voltage modded for 20volts just the same as MB voltage mods.

JessFM Here

knows how and powers 2 174watt peltiers at 1800mhz almost.... he hasnt got the guide up yet but if u put a message up there im sure he will tell u.


more details
Here

[Overlag]

This place sells the PSU's in the UK
http://www.wsplc.com/

[mr Voodoo]

Well, you could build your own PSU.

Almost done with my own now, 18V 50A, enough for 4 drift 0,8 =) and it cost me about 100$.

[Butcher]

I built my own, still needs an extra heatsink and testing but it's specced for 20V @ 25A and cost about $75, mainly for the transformer.

[Petrus]

mr_Voodoo AND Butcher:
1) Is it a linear or at switching PSU?
2) Dimensions and weight?
3) What about EMI, you figure it is safe to build it into the computer chassi?
4) Blueprint/guide/shematics?!

[Butcher]

1) Is it a linear or at switching PSU?

mine is linear, switching are very difficult to make, I've had a thought about modding a standard comp psu to put out just 20V or similar though, no progress yet.

2) Dimensions and weight?

Well I built it to fit a space, you could make it smaller but at least 80mm tall for fans / transformer, then you need it about 6 to 8 inches long and maybe that much wide, or longer and thinner etc.
As for weight it's about 4 Kg which is about half the weight of a computer (air cooled).

3) What about EMI, you figure it is safe to build it into the computer chassi?

I used a torroidal transformer as they are cheaper and lighter for a given amount of power, and also have very good EMI characteristics, if building into a case you'd almost certainly need it in a metal case (which you should do anyway to cover the AC line connections), that should help cut EMI, if it;s still a problem you could probably do some shielding with nickel paint or similar.

4) Blueprint/guide/shematics?!

hehe, I have a schematic for the circuit but it's just drawn by hand in my notebook atm, I could dig it out and get it into electronic form if you think it'd be useful.
As for a guide, I drew the circuit from scratch then just assembled it according to the schematic, it's not a particularly conplex circuit.

Specs of the circuit are:
Voltage 20V nominal (can be adjustable if required).
Max current: 25A (could be increased/decreased with different components).
Heat output: approx 50W, fan-cooled (dual 80mm) Al heatsinks used.
Cost: transformer (20-100 depending on size, location, etc.) plus about 10 bucks of stuff, heatsinks would probably cost an extra 10 bucks or so, I had some lying about.

Extras I could throw in include sensors for the fans so they run slower when the psu is cool (couple of bucks for them), a sensor on the coldplate to drop the psu voltage when it gets cold enough (although I think that might blow my current design to bits )

[Overlag]

diagrams here
http://www.arcobel.nl/~dabit/h2o_coo...elt/index.html

[Butcher]

hmm unregulated has the problem that you can end up with the voltage varying if there's any load variation and as peltiers probably change resistance with temp you can have some odd fluctuations. Also if you change the load (eg. change to 172s instead of 120s etc.) then the voltage is likely to change, and to get a reasonable level of smoothing you need a lot of capacitors. One thing you should also check with the capacitor is it's specified max ripple current as if you exceed that you'll end up blowing the capacitors (can be messy as they do literally explode).

[RedTalon19]

well i will be running dual 172s but only at about 15-16v so the power draw isnt such a problem. i will be using 1 SEC 1223 psu which i got for just over $100 but can be found for as little as $80 i think. i forget the exact specs but it does deliver a good amount of amps at higher voltages, but barley not enough for 2x172 tho which is why i'm aiming for only 16v

[Brad]

you could use those 550w psus.....

they are 5v, 85A

just use four of them for 20v, 85A, or five of them for 25v 85A