These thermoelectric elements and their interconnects typically are mounted between two thin metallized ceramic substrates, which provide structural integrity, insulate the elements electrically from external mounting surfaces, and provide flat contact surfaces. These carriers move the heat energy through the thermoelectric material. The module illustrated in figure 1 has two pairs of n and p elements and would be termed a two-couple module. By varying the input current from zero to maximum, one can adjust and control the heat flow and temperature differential. Modules can be mounted in parallel to increase the heat-transfer capacity, or they can be stacked in multistage cascades to increase the temperature differential.
Thermoelectric modules have no moving parts, so they are virtually maintenance free.
They are also smaller and lighter than comparable mechanical cooling systems. Their solid-state construction ensures high reliability, which is an advantage when they are to be used in a system that is not easily accessible after installation. Operation is acoustically silent, and electrical interference is negligible. For most applications, a standard module will be satisfactory, but custom designs are readily available. These answers should yield enough information about the system in which the module is to be installed to permit module selection.