n thermo-electric cooling system, the installation of TECs is very critical. Basic principles should be abided by during installation, or it may result in bad performance and reliability. There are a few factors to be considered in designing and installing the thermo-electric cooling system, as below.
TECs have a high mechanical strength, but a relatively low shear strength. Therefore, do not place TECs in a mechanical system that plays a major supporting role.
All the interfaces in the system should be in parallel, smooth and clean, in order to reduce the thermal resistance. High thermal conductivity materials should be used to guarantee good contact among surfaces.
Hot end and cold end of thermo-electric cooler can be told by the positions of the leads. The lead is usually soldered on the surface of the hot end, which is connected to the heat sink. For those TECs using insulated leads, red lead and black lead are connected to the anode and cathode of DC power supply. Heat flows from the cold end of the TEC to the overall TEC and then to the heat sink. For those TECs using bare leads, when the lead is facing the observer and the base of the leads is downward, the anode is connected to the right side of the TEC, and the cathode to the left side.
When the temperature is lower than the ambient temperature, the object shall be cooled with air insulated as far as possible, in order to reduce heat loss. Moreover, in order to reduce convection loss, blow the air directly to the object instead of installing fans. Meanwhile, it's necessary to avoid the direct contact between the cooled object and external structure unit, which helps reduce convection loss.
