Heat Dissipation in Electrical Enclosures Posted on February 17, 2017February 17, 2017 by Brandy McNeil Selection Procedure: Determine input power in watts per square feet by dividing the heat dissipated in the enclosure (in watts) by the enclosure surface area (in square feet). Locate on the graph the appropriate input power on the horizontal axis and draw a line vertically until it intersects the temperature rise curve. Read horizontally to determine the enclosure temperature rise Example: What is the temperature rise that can be expected from a 48″ x 36″ x 16″ enclosure with 300 watts of heat dissipated within it? Solution: Surface Area = 2[(48×36) + (48×16) + (36×16)] divided by 144 = 42 square feet Input Power = 300/42 = 7.1 Watts/SqFt. From Curve: Temp. Rise = 30°F (16.7°C)
