The function diagram for a Peltier module allows one to determine its performance under given conditions. More specifically, it can be used to determine how much heat can transfer from one side of a Peltier module to the other. In the example shown on this slide, assume there is a 12V_DC power supply that can source 15A (180W). Utilizing Same Sky's CP150 series of Peltier devices, the hot side will be held at 27°C and the cold side will be cooled down to 0°C. Start by marking the input voltage with a dot (1) on the vertical axis at 12V_DC. Next, mark the ∆T with a dot (2) on the horizontal axis at 27°C. Drawing a horizontal line from the input voltage dot and a vertical line from the ∆T dot, one can see that the two lines intersect (3) between the 9A and 12A lines. This results in the estimation that the Peltier module will consume approximately 11A of current under the specified conditions. With that 11A figure, mark another dot (4) on the lower “Heat Pumped, Q (W)” section of the diagram. Finally, by drawing a horizontal line from that dot back to the vertical axis, the resulting answer of approximately 65W (5) being transferred from one side of the Peltier module to the other is observed. If preferred, the approximate 65W of thermal transfer can be converted to BTU per hour using the ratio of 3.412 BTU per hour per 1W, giving a figure of 222 BTU per hour.