Description

The CSD 3 was designed as a means of automating the process of measuring sunshine duration for meteorological agencies and replaced the traditional Campbell-Stokes recorders, which only provided highly subjective results from manually checked burn marks on card. The CSD 3 will provide a clear sunny/not sunny output along with an actual value for the calculated solar irradiance.

Sunshine duration is defined by WMO as the time during which the direct solar radiation exceeds the level of 120 Wm². Sunshine Duration Sensors are widely used in weather networks to provide the number of sunshine hours per day for tourist information. In agriculture the CSD 3 monitors the amount of sunshine received by crops. In building automation it can be used to automate the control of sun blinds.

The CSD 3 has no moving parts and uses 3 photo-diodes with specially designed diffusers to make an analogue calculation of when it is sunny. The output is switched high or low to indicate sunny or not sunny conditions. The calculated direct irradiance value is also available as a mV output.

The CSD 3 requires a 12vDC power supply and has a two level built-in heater to dissipate rain, snow and frost. The heaters are normally switched externally but an optional internal thermostat control is available to allow this to be automatically controlled. The unit also includes a replaceable drying cartridge that will remove internal moisture and the CSD 3 includes a humidity indicator to show when this should be replaced.

Features

• Waterproof plug-and-socket cable connection for easy installation and servicing
• Humidity indicator to show when a change of drying cartridge is necessary
• Larger capacity drying cartridge that is easier to change at reduced intervals
• Low maintenance at long intervals
• Glass tube, for improved resistance to scratching by storm-blown sand and ice
• Operating temperature range extended, -40 to +70ºC

Specifications