Thermoelectric Cooling

[Modding_out]

Dude! that's awesome! for 7.99 do you guys think I can stick that thing between my AMD Sempron CPU and it's huge heat sink? Or should I just go with a professionally made unit? I would love to give my cpu frost bite.....

[BrianG]

Originally Posted by J57ltr

Brians right it takes a lot of current and they will never handle the loads placed on them in a RC. I have used them for a lot of things playing around with them and they are very fragile, basically you have 2 ceramic plates with a bunch of what look like surface mount caps sadnwiched between (these are the PN junctions). Wiki is not the area you want to look for real information on this (or anything else for that matter). They are very brittle and can break easily Shear loads are real bad on them and I have ruined a few just from dropping them on a table.

Go here then start reading the rest of the info at the bottom of the page. There are a few.

http://www.ferrotec.com/technology/t.../thermalRef01/

a module that will draw 6A @ 12V will pump about 170 BTU's. With 6 of these modules I was able to pull a 2# block of aluminum down to 5.5F in 20 minutes using a water cooled system And drew over 36 amps continously. I have a little one that will bring a small heatsink to the point where it's white from condensation in a few minutes using a 3S A123 pack, but it draws 4 amps ALL THE TIME. I have it graphed in my eagle tree, I'll post it up when I get home. I also have a module that will draw 30 amps all by itself.

And you can also generate power with them as well, pretty cool


http://www.rc-monster.com/forum/showthread.php?t=23193

There is a pic in this thread with the water cooled one I made.

I thought I remembered them being fragile too, but wasn't sure so I didn't post it. I too did some experimenting a while back, and they are pretty interesting. It's been a long time (and I don't feel like searching right now), but I have a question for you. I understand the application of current causes heat to be pumped from one side to the other. Now, let's say we are applying 12v @ 5A through a device. How much of that 60w is being dissipated as heat on the hot side? In other words, what is the efficiency. So, not only do you have to get rid of the heat being pumped, you also have to get rid of the heat produced from any efficiency losses.

Originally Posted by Modding_out

Dude! that's awesome! for 7.99 do you guys think I can stick that thing between my AMD Sempron CPU and it's huge heat sink? Or should I just go with a professionally made unit? I would love to give my cpu frost bite.....

You might need to either get a fairly large one, and/or stack them. They have a limited delta temperature rating, so the amount of cooling you get will be determined by the ambient air temperature, the amount of heatsinking you have, current flow through the device, and the device rating. I'm sure I don't have to tell you that if the device cools below room temperature, you will get condensation. So, your CPU will get frostbite, but also get waterlogged. Not good.

[J57ltr]

Brian,

On the efficiency 2 numbers pop into my head 30% and 65%, I'll look it up I have the notes, I think here at work.

You really need a large heatsink on the "hot" side (if you reverse polarity the change sides), they are capable of 70F temperature differentials so the colder you can keep the hot side the colder it gets on the cold side.

Think of this if the air temp is 100F and you can keep the hot side at 135F then you can only get the cold side to 65F. I used large fans or water cooling for my large projects. One thing you have to deal with on electronic applications is condensation. I shorted out a few devices (was able to fix them but that is another story), just because of that. They are really cool I have a dual probe digital temp (K-type) that I tracked temps with. It’s really neat to see the condensation form and then all of a sudden it starts turning to ice all across the plate.

Jeff