Finally making a little progress...

[WizardG]

Finally making a little progress on the TEC cooled '07 I've been wanting to put together. The host will be an old bar code scanner gun. @ 12volts in, with the TEC wired in series with the driver input, diode current is @ 3 amps, output power is about 3.5 watts, and the diode is sitting at 12 degrees C. I need more cooling air before I can push the TEC any harder as it starts losing ground to the diode heat above 3 amps to the diode with the dinky blower shown in the photos. Hot side of the TEC was @ 58C after a half hour run.

 

[Deleted member 17304]

Hey, you'll need to upload the pics to the forum or some other hosting site. We can't look at your C: drive

I am curious as I want to set up one of the 490s in a lab style build with some sort of active cooling.. I'll be staying tuned

 

[WizardG]

Hey, you'll need to upload the pics to the forum or some other hosting site. We can't look at your C: drive
Fixed. Thanks.
I am curious as I want to set up one of the 490s in a lab style build with some sort of active cooling.. I'll be staying tuned[/QUOTE/]
How far were you thinking of going with the cooling? Temperature tuning or just stabilization?

 

[Cyparagon]

You'll also want to insulate the cold side. You're gaining heat from the air, and while not a huge contributor, it will worsen with a larger fan. It's an easy fix.

the TEC wired in series with the driver input

Are you sure you don't mean parallel?

 

[WizardG]

You'll also want to insulate the cold side. You're gaining heat from the air, and while not a huge contributor, it will worsen with a larger fan. It's an easy fix.

Are you sure you don't mean parallel?

Nah, I hooked things in series for first light. The final product will need a separate driver for the TEC. I think an SXD will do but I might need something like a black buck 8 if I want any headroom. I want to find out how much extra power this diode will give me @ 5 amps @ 0C.

 

[RedCowboy]

I'm also making a cooler for a module I want to keep at 70F, it will dissipate 25-30w of waste heat.

The junctions in your TEC have a minimum voltage and you will draw around 1/4 the current at 6v as at 12v so remember that it's not linear, I will likely use a thermistor and a comparator/op amp to switch mine on and off and power it at 12v rather than adjusting the voltage, ebay also sells an inexpensive temperature controller that does this.

My TEC pads take 12v @ 8a for 92w.

Actually I will use this temp controller with 3 x 26650 cells in series minimum for a 9a draw, also run my fan, same 12v powers the TEC through the temp controller relay and powers the temp controller itself. : Hot side of TEC will have aluminum fins and small fan, cold side a copper slab for my diode module.

I will use a separate battery pack for my LD/driver.

https://www.ebay.com/itm/DC-12V-W12...572439?hash=item3d613fbe17:g:7qQAAOSw6YtZW8n2

I also grabbed a couple of these 60w, 12v @ 5a with fins attached. > https://www.ebay.com/itm/12V-60W-Th...e=STRK:MEBIDX:IT&_trksid=p2060353.m2749.l2649

 

[Cyparagon]

The final product will need a separate driver for the TEC. I think an SXD will do...

Why? They don't need to be current regulated and a driver wastes energy. Run it at a full 12V, or use PWM and drive it with a FET instead.

 

[WizardG]

Why? They don't need to be current regulated and a driver wastes energy. Run it at a full 12V, or use PWM and drive it with a FET instead.

I'll need regulation of some sort to avoid condensation. I was thinking of an arduino controller with humidity sensor to run the diode as close to the dew point as I dare. That could control the modullation input of an SXD. And the SXD is pretty efficient so..why reinvent the wheel?

 

[Cyparagon]

so..why reinvent the wheel?

Precisely! You want to regulate temperature, use a thermostat. That's what normal people do . They're $2 shipped on ebay and require no additional circuitry or mucking around.

This "arduino plus hygrometer plus thermistor plus constant current driver plus software tweaking plus modulation link" IS reinventing the wheel... by adding corners to it. Not only is it unnecessary, it is expensive, takes longer to set up, occupies a larger space, is less efficient, and is far more prone to failure.

 

[Mattronium]

WizardG, are you trying to get the diode as cold as possible before condensation happens or just run it at a specific temperature.
It wouldn't be very hard to use an arduino for pwm for the TEC and a thermistor for temperature feedback. That is what I am using for my experiments.

 

[dressur4]

That is cool.

 

[trinh hong phuoc]

great heatsink-30 min