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TEC Cooling Condensation Concerns

Gazoo

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Condensation will happen when a module is cooled below the ambient air's dew point. I have cooled my module well below the ambient temperature and there has been no condensation. Following is a calculator that will help you determine how much you can cool your module and not have to worry about condensation:

http://www.decatur.de/javascript/dew/index.html
 



Gazoo

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I am running the air conditioning. The humidity is 60%. But it doesn't matter. If you use the calculator you will find you can keep the module cooler than the ambient air temperature even under very bad conditions, and it will not condensate.
 

Gazoo

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No problem. In fact I thank you for bringing it up. It made me wonder why the module wasn't condensating, so I did a little research on google and found the calculator.. :)
 

Hemlock_Mike

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I use the backwoods method -- If it's cool to the touch, that's about right. Dewpoint is the "critical" temp where you can start getting water but that's usually well below the needed heatsink temp.
Don't push the TEC too hard or you will need to get rid of that excess heat too.

Mike
 

Daedal

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Exactly.

I cool mine to the point where they are just cool enough. You don't really need to get them to freeze. A good measure is to hook up the TEC and try it out with some water droplets before you put on the module. Simply get the water to be cold, but not freezing. :)

I managed to push one of SenKat's diodes up to 600mA with that kind of cooling. :D

--DDL
 

Hemlock_Mike

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DDL --

My initial testing of the GB diodes indicates that 400 mA is about the knee of the output curve. I didn't read any more power at 500 ma. - at least not enough to blow up the earth ;D

Mike
 
P

Plug

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Personally I am a total laser noob ::) but i have dealt with TECs and some more advanced forms of computer cooling and a great way to control condensation is by using liquid electrical tape :D

Trust me, it easily seals up areas and is easy to peel off
 

Cyparagon

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So if TEC is thermo electric cooling, what is TEC cooling? Is it anything like an ATM machine or a PIN number?
 

Gazoo

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Those are way overpriced...keep an eye on ebay for small peltiers...they often show up.
 

Archane

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one question since i've had very little exp with pelts, on a few sites they refer to potted and unpotted peltiers, it sounds like they come with a way to control the current already, or am I way off?
 

Gazoo

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Archane,
I am using Daedal's circuit to regulate the current going to my peltier. The max voltage of mine is 5 volts, but I only need about 1 volt to keep the diode cool. I keep it a little cooler than room temp. This prevents condensation and keeps the diode happy. ;)
 

Archane

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yeah my goal is to use DDL's circuit also. I have it built on a breadboard right now(will be starting my own post about that today with pics)

You may have answered my question already then, the circuit powered by 2 cr123 batteries has enough power to drive the LD and a pelt?
 

Gazoo

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Archane said:
yeah my goal is to use DDL's circuit also. I have it built on a breadboard right now(will be starting my own post about that today with pics)

You may have answered my question already then, the circuit powered by 2 cr123 batteries has enough power to drive the LD and a pelt?
Once the circuit receives less than 6 volts the current will begin to drop. The better solution is to find a regulator with a lower drop out voltage. I will need to check how much current my peltier is drawing, but I think it would be possible using a small peltier...like one with a rating of 4 watts.

http://cgi.ebay.com/Melcor-CP-0-8-31-06L-Peltier-Thermoelectric-cooler_W0QQitemZ150127216975QQihZ005QQcategoryZ4660QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
 







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