More Power - What are people using for TECs?

[Chill-X]

Ok, so my last idea wasn't soo good (AT P/Ss) for powering TECs, I'll ask this question:

What are people using to power their TECs?

I'm especially interested in hearing from people with multiple TECs in one system.


BTW - I'm working on a Double Stacked Peltier setup and watercooling. My case for this project already has mounts for 3 Power supplies (personally modded), but no room for watercooling components. It's a SCSI setup and currently running one PS for the SCSI drives and one for the MB/cards/fans. I figure I have enough spare 12V somewhere for one TEC, but not two. So I need to come up with another Power supply for the second TEC. This project may migrate to a duallie system eventually and possibly with 4 TECs!! So, I need something with capacity to expand. Ie - If I get a 550W P/S now - that'll be enough for 2 TECs, but what about 2 more?


I was out browsing today in various shops and noticed some 13.8V DC P/Ss meant for auto accessory use. I recall one in the range of 20-25 A for $90. How well do TECs work at 13.8V instead of 12V? I have some 80W (and I think 16V max) TECs currently.

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I must be a crazy cooler - I bought more in cooling stuffs than in new hardware in the past several months.

[BillA]

I doubt you'll run stacked TECs very long, it's a most demanding design/application.
Note that the second TEC must handle the heat of the CPU plus the heat from the first TEC. Normally this is done with an intermediate cold plate and a larger (higher capacity) second TEC.

TECs are most efficient at about 80% of Vmax, above that it's mostly internal heat thats being generated.

Check out eBay for PSUs, I got a $335 unit for $30 + $17 shipping.

be cool

[Joe]

Really the best thing you can do is try and find a purely 12V - 13.8v PSU. with a standard Comp PSU you need to dumy load the 5v to get to 12v on the 12v rail.

That can be sort of a pain.or build one custom ( or have a friend or someone who knows electronics damn good to make one) Why cant they just make some 120VAC pelts? hehehehehehe or just a nice big 220V 100A Pelt you could cool yer office building with that beyatch heheheh

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C-ya
Joe - Owner/Editor
www.ProCooling.com
Where the Completely Addicted Come to Cool Off

Somebody set up us the bomb.

[Chill-X]

Well I was starting to think that too. I saw some 13.8V DC PS for Ham use - they looked pretty good.

120VAC or even 220VAC pelts - HA! will never happen. Although you could see 120V pelts - but DC.

Actually if you had a use for a bunch of pelts, you could just string pelts in series to get to around 120V between all the pelts. Then to power, just use a recterfier (sp?) and some BIG-ASS filter caps to get you a nice 120V DC power supply. You could actually use just a reterfier, but the output voltage will not be constant.

Hmm, maybe if I had a use for 6 to 12 pelts, I would try this out.

[Freakyfrank]

these babies work fine at 13.8V...

i was also thinking about a 22A 13.8V supply...

but now i'm gonna custom build myself a 16V 32A one.. (i want to get the FULL 156W x2 hehe)

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OC'ing is my middlename

[melteye]

i was seeing if my power supplies could live up to their peltier powering... with a digital probe it reads 12v... so whats this about dummy loading? or do you mean the 5v dummy load to get amperage on the 12v rail up

[spyizme]

so now i can set a temp that i want to keep with the VPC-160, so there is no condensation. this monitors the tec and it doesnt let it get too cold or too hot.

[ondaedg]

Here is an alternative for ya:
http://www.procooling.com/articles/h...chnology.shtml

[Fig]

Quote by ondaedg
"First off, we must connect the 1 or 2 ohm resistors I mentioned in the supplies list across the +5 volt connections. In other words, one end of the resistor must go to one of the red (+5v) wires and the other end of the resistor must go to one of the black wires (negative)."

So basically a +5v red lead stemming from the pcb goes to the 1 or 2 ohm 25w resistor, to a black(negative) lead stemming from the pcb. Is this correct? If my pelt has a molex connector, I can plug it into either of the power supplies, correct? What do I do with the leads that were cut? I don't think I exactly understand it. Any help would be greatly appreciated! Thx

[Freakyfrank]

Originally posted by Fig:
[b]Quote by ondaedg
"First off, we must connect the 1 or 2 ohm resistors I mentioned in the supplies list across the +5 volt connections. In other words, one end of the resistor must go to one of the red (+5v) wires and the other end of the resistor must go to one of the black wires (negative)."

So basically a +5v red lead stemming from the pcb goes to the 1 or 2 ohm 25w resistor, to a black(negative) lead stemming from the pcb. Is this correct?

- yup.. just have a dummy load on the 5V rail.

If my pelt has a molex connector, I can plug it into either of the power supplies, correct?

hmm... u missed me here..
1 - make sure the pelt voltage rating is above 12V..
2 - plug the wires into the 12V output of the psu.. either on the PCB or just on a connector. (yellow = +12V)

What do I do with the leads that were cut?

why do u want to cut the leads?

[Fig]

quote:
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Fig:
What do I do with the leads that were cut?
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Freakyfrank:
why do u want to cut the leads?

So i should solder the dummy load onto the pcb?

That makes much more sense than what I was imagining! :P Thanks!

[Cerelac]

I built a 12V 10A supply from a large transformer rectified with a bridge and filtered with 2 10000uF electrolytics. Simple, robust, and works great. AC input fluctuation isn't a big deal.

[imagex]

I jsut got a 24 volt 20 amp power supply very high dollor deal "got it free",now my problem is to many volts. it's just right for my drift 24 volt pelt but i want to run pumps @13 volt also ,I've been looking for weeks for a good "cheap" way to cut the volts and adjust "fine tune" volts.so far the best idea is resistors,but thats a lot of heat useing a bunch of 10watters.need more idea's ,got any???

[resago]

got anything you can run the pump in series with? - got 2 pumps?

[Rotax]

well my old technology psu pushes 1-19v 47A

[Butcher]

Imagex, you want a regulator of some sort. Two type available - linear and switching. Linear are cheap and simple normally it's a 3 pin package, only thing to worry about is heat. Switching put out a lot less heat put are slightly more expensive and are more complicated, you can find some fairly well integrated units with about 10 pins which would do the job. without too much external circuitry.

[hielko]

If it's only the pomp you have to deal with it can be done with a liniear regulator. Even without transistors. I believe the LM350 can handle 5 amps and 1.25-37V. Just remember the heat output of the regulator is 11V * Amps pump = lots of heat.

[andy]

I can't agree more on the topic of linear power supplies. They are just not practical at all when you are talking hundreds of watts.

I wanted a variable voltage power supply that was practical and able to power my 4 172W (24 V) TECs. After lots (and lots) of research, I found the perfect unit in allied electronics (alliedelectronics.com) It is a solid state switching variable voltage AC power supply. (0-120V AC @25amp, ~$130) Of course the output is AC, so I needed to rectify this to DC and add substantial capacitors to take out the voltage ripple. This is not a very big deal though, you can ready about it in any book on power supplies.

The end result was a fully adjustable 0-120+ DC @ 25amp power supply that fits inside my case. This is enough for something like 10 172 pelts. I strongly encourage other people to go this route, as I consider it crucial to have adjustable voltage, and PC power supplies just don't cut it.

[jastrckl]

imagex: you should look into voltage divider circuits. powering another device in series that doesn't have the exact same current draw won't work well... one of them will suck up the majority of the volts. Aside from that, maybe a solid state voltage controller.

[pmoores]

At least for the Tec on dangerden (152w) you might want to consider a bench power supply like the one at: http://mpja.com/product.asp?product=12640+PS .

It matches the 152w perfectly, slightly low on voltage but you dont run the pelt at 100% anyways. Its hard to find a bench that matches amps and voltage well. This one does up to 25amps but is adjustable from 0-15volts.

There are one or 2 others out there but the other close match stops at 10amps with higher voltage. The rest are little 3amp types or fixed 12.5v models.