Specifications

CNR4 Net Radiometer
2.2 Pyranometer Specifications
* indicates ISO specifications.
Spectral range:
305 to 2800 nm (50% points)
Sensitivity:
10 to 20 µV/W/m
2
Response time*:
< 18 seconds (95% response)
Non-linearity*:
< 1% (0-1000 W m
-2
irradiance)
Non-stability*:
< 1%
Temperature dependence of
sensitivity*:
< 4% (-10° to +40°C)
Tilt response*:
< 1% at any angle with 1000 W/m
2
Directional error*:
< 20 W/m
2
at angle up to 80° with
1000 W/m
2
Zero offset due to 0 to -200 W/m
2
IR net irradiance*:
< 15 W/m
2
Zero offset due to temperature
change*:
< 3 W/m
2
(5K/hr temperature change)
< 1 W/m
2
(with CVF 4 installed)
Operating temperature:
-40°C to +80°C
Field of view
Upper detector:
Lower detector:
180°
150° (due to lower solar shield to
prevent illumination at low zenith
angles)
Maximum solar irradiance:
2000 W/m
2
Expected accuracy for daily totals:
±10 %
Typical signal output for
atmospheric application:
0 to 15 mV
Impedance:
20 to 200 Ω, typically 50Ω
Detector:
Copper-constantan multi junction
thermopile
Level accuracy:
1 degree
Irradiance:
0 to 2000 W/m
2
Spectral selectivity:
< 3% (330-1500 nm spectral interval)
Uncertainty in daily total:
< 5% (95% confidence level)
Instrument calibration:
Indoors. Side by side against reference
CMP3 pyranometer according to ISO
9847:1992 annex A.3.1
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