The BF5 Sunshine Sensor measures Global and Diffuse Radiation and sunshine duration.
The BF5 sunshine sensor is a multi-purpose solar radiation sensor. It uses an array of photodiodes with a unique computer-generated shading pattern to measure incident solar radiation. A microprocessor calculates the global and diffuse components of the radiation and determines the sunshine state.
Two analogue voltage outputs are provided, one for Global Radiation, and and one for Diffuse Radiation. The sunshine state is represented by a digital output (contact closure). The three outputs can be connected to appropriate channels on a wide variety of environmental data loggers, including the Delta-T Devices GP2 and DL2e.
The BF5 measures sunshine hours indirectly using a simple effective equation based on the total PAR radiation and the ratio of total to direct PAR. This algorithm corresponds closely to the World Met Office threshold of 120 W/m-2 in the solar beam for sunshine duration.
An internal heater keeps the BF5 clear of dew, ice and snow down to -20°C.
Typical building design and meteorological applications include integration into Building Energy Management Systems (BEMs), heat balance and natural light studies, and the monitoring of solar energy projects.