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I am making a mini-fridge. On one side is a 150mmx150mm aluminium plate. It has been roughed up to increase surface area. On the other side it has an aluminium CPU cooler which can survive the tdp of the peltier.

I have:

2 x TEC1-12706, 4 x Fan 12V @ 0.2A

A TEC1-12706 is a peltier thermo-electric pad that emits cold on one side and hot on the other. This operates at 12V and at max, 6A. Hence the 12 and 06.

Say if I had a 12V dc power supply, how would I proportion the correct amount of current to these components? So if I want 6A each going to the peltier cooler and the remaining 1A for the fans.

I was thinking a potentiometer will do it but it would not be the best and efficient way.

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  • \$\begingroup\$ Are you trying to control the temperature of something to a specific temperature, or just cool it as much as possible? \$\endgroup\$ – The Photon Jun 19 '17 at 20:37
  • \$\begingroup\$ What is a TEC1-12706? Please edit your question to explain it, say what current you think it needs and provide a link to the datasheet. \$\endgroup\$ – Transistor Jun 19 '17 at 20:47
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    \$\begingroup\$ The fans will just draw the current they require, when supplied with the correct voltage. You don't need to do anything to proportion or control the fan current. Just "roughing up" (sanding?) the Al plate won't significantly improve its heat dissipation ability - you really need a proper heatsink with lots of fins to dissipate the heat. \$\endgroup\$ – Peter Bennett Jun 19 '17 at 22:16
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If you use a resistor divider to regulate the voltage you are going to waste energy as heat through the resistor. Another problem that TEC control presents is the load is dependent on the temperature across the device. So simply limiting the current or voltage will not give you a stable temperature. A better way is to use a DC to DC or voltage regulator to control the energy into the peltier.

A thermal sensor is needed to control the peltier. The modules can sink up to ~60W of energy and 6.4Amps max with the voltage being no more than 16V.

With two modules you'll need around 120W of power and a 15V (or 16V) supply. I suppose you could go with 12V to match the fans (and another 10W) but you'll limit your power.

Here is a great article on peltier control. This is just an example, there are other controllers and some don't require a microprocessor for thermal monitoring.

If you do not insulate the box of your 'mini fridge' adequately the peltiers will not be able to pump heat out of the box fast enough and the temperature will not drop.

enter image description here

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    \$\begingroup\$ If you like the answer upvote \$\endgroup\$ – Voltage Spike Jun 19 '17 at 21:58

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