Casper, you can't just add a resistor, the resistor would never take that much energy dissipation. And a POT would probobly go out in a blaze of glory.
Peltiers come in many shapes, sizes, and power ratings. Including different voltages. I will admit that you can often hook them to a 12V rail without out a problem. Why?, because many of the ones that are available on the user market were purchased by suppliers that intended to sell them individually to the average user who would most likely use a 12V source such as mounting it onto a CPU. However if the chips are bought from an actually electronics parts supplier (not talking about radio shak or Jameco) then they could be for any voltage. I some cases the design may require that the chip run off five volts with much higher current, or a much higher voltage with lower current. If you check out a web site of a peltier manufacture you'll get a good idea of what is really available.
Of course I have no idea where lithopsman got his chips, in all likelyhood they are 12V, but it is better to be sure.
Joe
Peltiers come in many shapes, sizes, and power ratings. Including different voltages. I will admit that you can often hook them to a 12V rail without out a problem. Why?, because many of the ones that are available on the user market were purchased by suppliers that intended to sell them individually to the average user who would most likely use a 12V source such as mounting it onto a CPU. However if the chips are bought from an actually electronics parts supplier (not talking about radio shak or Jameco) then they could be for any voltage. I some cases the design may require that the chip run off five volts with much higher current, or a much higher voltage with lower current. If you check out a web site of a peltier manufacture you'll get a good idea of what is really available.
Of course I have no idea where lithopsman got his chips, in all likelyhood they are 12V, but it is better to be sure.
Joe