To accurately measure the outdoor air temperature, an outdoor temperature sensor must be insulated from the direct and indirect effects of the sun and allow sufficient airflow directly to the temperature sensor. The direct effect of the sun is the infrared energy received directly from the sun. The indirect effect of the sun is the infrared energy that is continuously reflected and absorbed and re-emitted from all objects such as plastic and metal shields and surrounding objects. These indirect sources include the ground, control cabinets, and the sunshield itself. Man made sources of heat also emit infrared energy. Examples include cars, electrical transmission and distribution transformers, etc.
The Demico Inc. Temperature sensor Sun Shield uses a solid piece of redwood to enclose and insulate the sensor from natural and manmade sources of direct infrared energy. Strategically placed holes in the redwood allow sufficient airflow to keep the sensor equal to the nearby air temperature.
Since the sunshield is constructed from solid redwood, no stain or paint is required. The exterior of the sunshield will weather naturally to a grayish color. Light colored stains may be applied if desired, as well as water protective products designed for wooden decks. Spraying or coating the inside of the sunshield is not recommended. The sunshield is assembled with wooden dowels, and good quality outdoor wood glue for a long maintenance free service life. The galvanized pipe flange base allows simple mounting using standard threaded pipe or fittings.