I really need some help with peltier cells

[warini]

I need to know if i can invert a peltier polarity (instead of conecting ++ -- do it like +- -+) to invert the hot and cold faces.

Please answere as soon as posible, is for a proyect in university.

THANKS

 

[Russlk]

Do you mean there are 4 terminals on the device?

From my dictionary: Peltier effect - The production or absorption of heat at the junction of two metals when current is passed through the junction. Heat generated by current in one direction will be absorbed when the current is reversed.

It would appear that you only need to reverse the connection.

 

[warini]

no there are not 4 terminals, I mean instead of conecting the positive where the positive goes, i conect the positive where the negative goes and the negative where the positive goes, I wanna know if that changes the hot and cold faces.

 

[Russlk]

Yes, I believe it does. Try it, it cannot hurt.

 

[Platonas]

It should work fine, it is a method used to reverse hot and cold surfaces.
In commercial coolers by turning a switch to another position, you have heating instead of cooling iside the "cooler".

 

[bmcculla]

You can reverse the terminals to change heating/cooling.

Peltier effect - The production or absorption of heat at the junction of two metals when current is passed through the junction

This is a bit misleading. The peltier device moves heat from one side to the other - it can't absorb heat. So the most important factor in how cold you can get the device is how effective your heat sink is on the hot side. The Peltier device does create resistive heating both when it's heating and cooling. This is why they are so much better at heating than cooling.