Campbell Sci – CS320 Solar Radiation

The CS320 is a digital thermopile pyranometer that measures broad-spectrum short-wave radiation and communicates over the simple SDI-12 protocol to the data logger. This sensor design eliminates measurement error and programming errors that can adversely affect data quality.

This pyranometer has been designed to improve the global solar radiation measurement significantly (even under cloudy conditions) without adding substantial cost. The CS320 is suitable for applications ranging from environmental research to agriculture to large mesoscale weather networks (mesonets).

The CS320 is manufactured using a high-grade anodized aluminum body and IP68-rated 316 stainless-steel M8 connector (marine grade). The CS320 sensor is heated (on/off switchable under user control) and allows continuous operation in changing environmental conditions. The pyranometer’s calibration data is stored on the sensor.




ISO Classification Class C (second class)
Calibration Uncertainty ± 2.6%
Measurement Range 0 to 2000 W/m2 (net short-wave irradiance)
Measurement Repeatability < 1%
Long-Term Drift < 2% (per year)
Non-Linearity < 1%
Sensitivity 0.057 mV/W/m2
Detector Type Blackbody thermopile
SDI-12 Response Time 2 s
Field of View (FOV) 180°
Spectral Range 385 to 2105 nm (50% points)
Directional (Cosine) Response < ±20 W/m2 (at 80° solar zenith)
Temperature Response < 5% (from -15° to +45°C)
Output SDI-12 (version 1.4) 1200 bps
Zero Offset A 8 W/m2
Zero Offset B < 5 W/m2
Operating Temperature Range -50° to +50°C
Operating Environment 0 to 100% relative humidity
Heater 0.2 W (on-board)
Heater Power Requirements 25 mA current drain (at 12 Vdc)
Input Voltage Requirements 6 to 24 Vdc
Current Drain
  • 5 mA (measurement)
  • 3 mA (standby)
Uncertainty in Daily Total < 5%
Error Due to Clouds ±2 %
Mechanical Rating IP66/68
Factory Calibrations Traceable to secondary standard blackbody thermopile pyranometers traceable to the world radiation reference in Davos, Switzerland.
Warranty 4 years against defects in materials and workmanship
Diameter 3.43 cm (1.35 in.)
Height 3.96 cm (1.56 in.)
Weight ~65 g (2.3oz)
May vary due to potting.

Additional information


Campbell Sci