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Topic: Thermoelectric Cooler with Arduino? (Read 1 time) previous topic - next topic

1EAS1

I know I need a thermoelectric cooler and a n-channel MOSFET but do I also need a heat sink? I'm going to use it to heat stuff up to its limits 180•C and to do this do I need a heat sink? It's going to be in an enclosure so they purpose is to act like an oven.

adrian_h

What are you attempting to do? 

AFAIK, thermoelectric devices move heat energy around (as do other devices that act as a heat pump).  If you want something cold, the other side will become hot and if you want something hot, the other side will become cold.  Energy is not actually removed, just moved.  A heat sink may be required to dissipate the heat as the device can only have a certain temperature differential between hot and cold sides.  Putting heat sinks on one or both sides would allow for faster pumping of the heat energy.
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BillHo

Quote
Max Operating Temp: 180?
Min Operating Temp: -50?

Learn about TECs (Tom's Wiki)
Learn about thermoelectric effect (Wikipedia)
Example Arduino code to control a MOSFET for power
Code: [Select]
/*
SparkFun Electronics 2010
Nathan Seidle

This code is public domain.

Peltier ran at 3.6A @ 11.0V = 39.6W!

The thermo-electric cooler (or Peltier) works well well with a computer power supply for power, a computer
CPU heat sink for cooling and a N-Channel MOSFET to control the power. The Peltier is going to use a ton
of juice. In this case, I  measured 3.6 amps at 11 volts! I had to attach the hot side of the Peltier
to a large computer CPU heat sink but it worked so well that the cold side was so cold I could not keep
my finger on the device.

Because I was so scared of pumping 40 watts into a device, I used this program to slowly ramp
up the power flowing through the MOSFET. Press 'a' to increase power, 'z' to step down.

*/

int peltier = 11; //The N-Channel MOSFET is on digital pin 11
int power = 0; //Power level fro 0 to 99%
int peltier_level = map(power, 0, 99, 0, 255); //This is a value from 0 to 255 that actually controls the MOSFET

void setup(){
  Serial.begin(9600);

  //pinMode(peltier, OUTPUT);
}

void loop(){
  char option;

  if(Serial.available() > 0)
  {
    option = Serial.read();
    if(option == 'a')
      power += 5;
    else if(option == 'z')
      power -= 5;

    if(power > 99) power = 99;
    if(power < 0) power = 0;

    peltier_level = map(power, 0, 99, 0, 255);
  }

  Serial.print("Power=");
  Serial.print(power);
  Serial.print(" PLevel=");
  Serial.println(peltier_level);

  analogWrite(peltier, peltier_level); //Write this new value out to the port

}



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