The Kipp & Zonen secondary standard pyranometer is suitable for the measurement of solar irradiance on a plane surface.

The CM11 sensor with FTS designed SDI-12 interface, incorporates a 100 thermocouple sensor, imprinted on a thick-film substrate housed under K5 glass domes. The sensor is rotationally symmetrical. A white screen prevents the body of the pyranometer from heating up. A drying cartridge keeps the interior free from humidity. All pyranometers are supplied with a calibration certificate which also shows the level of directional error. This sensor has ISO 9060 secondary standard classification.

• Unsurpassed nighttime zero offset specifications (non-ventilated)
• Unsurpassed long-term stability of sensitivity.
• Unsurpassed levelling accuracy.
• Unsurpassed directional response.
• Active temperature compensation.
• Zero Tilt Error.
• Fast response time.
• Near perfect linearity.

Recommended for performance testing of solar collectors by the International Energy Agency (IEA)

The interface provides conversion from low level sensor output to digital SDI-12 format. The SDI-12 digital signal is low power and yet far more resistant to data errors than a low power analog signal, greatly reducing the likelihood of corrupt data due to interference. Calibration information for the sensor is stored within the SDI interface case which eliminates the need to enter calibration values in the datalogger.

SDI-SR-CM11 Specifications

Spectral range: (50% points) 305-2800 nm 
Sensitivity: 4-6 µV/Wm2 
Impedance: 700-1500 ohm 
Response time: (1/e) 4 s 
Response time: (99%) 24 s 
Non-linearity: (1000 W/m2) < 0.6% 
Tilt error: (1000 W/m2) none 

Operating temperature: -40°C to +80°C 
Temperature dependence of sensitivity: ±1% (-10 to +40°C) 
Maximum irradiance: 4000 W/m2 
Directional error: (at 1000 W/m2) < ±10 W/m2 
Weight: 0.85 kg 
Cable length: 10 m