Net Radiometer—Kipp & Zonen NR Lite2

The NR Lite2 net radiometer measures net radiation and outputs a single analog signal to the Sutron 9210B datalogger. Here are basic installation and operation guidelines for using the NR Lite2 in a LI-COR eddy covariance system that is running Biomet_100 or Biomet_102 programs.

NR Lite2 Specifications
Spectral Range: 0.2 to 100 μm
Energy Range: -200 to 1000 W/m2
Response Time: <20 s @ 63%
Nominal Sensitivity: 10 μV/Wm2
Directional Error: <3% up to 60°
Sensor Asymmetry: <15%
Operating Temperature Range: -30 to +70 °C

For more information and complete operating instructions see Kipp & Zonen:

  1. Siting the Net Radiometer.
  2. Install the net radiometer so its upward and downward views are unobstructed by adjacent structures, trees, and the meteorological station. Select a location that is away from heat sources or reflective surfaces.
    • Orient the sensor with the mounting rod pointing toward the north pole in the northern hemisphere or the south pole in the southern hemisphere to minimize shading effects.
    • Mount the sensor at least 1.5 m above the plant canopy.
    • Install the bird-deterrent stick.
  3. Mount the Net Radiometer.
  4. The NR Lite2 mounts to the 7900-350 Radiation Sensor Mount, which can be affixed to a horizontal cross-arm.
    • Attach the mounting brackets and band clamps to the plate.
    • Tighten the band clamps around the cross arm.
    • Attach the U-bolts to secure the radiometer shaft.
    • Rotate the radiometer as needed and adjust the leveling pins to level the sensor.
    • Tighten nuts to secure the U-bolts.
  6. Wire the Net Radiometer to the Datalogger.
  7. The NR Lite2 Net Radiometer is supported by datalogger programs Biomet_100 and Biomet_102. For custom programs, use the NetRad block and configure it as described in Net Radiometer (NR Lite2 or CNR4).
  8. Route cables through an opening in the bottom of the enclosure.Note: Route the sensor cable(s) through an opening in the enclosure prior to installing the leads in the terminal strip.
  9. Description Color AIO2 Terminals
    Signal Red 1 (CH1)
    Signal Ref. Blue 2 (CH2)
    Ground Black 3 (AGND)
  10. Enter the Calibration Constant.
  11. The calibration factor is printed on the sensor and also included with the product documentation. It indicates the sensitivity of the radiometer. Confirm that the serial number on the sensor corresponds with the serial number on the calibration certificate.
  12. The calibration factor (sensitivity), which is in units of μV/W m-2, should be entered directly into the datalogger software.
  13. Under the DATA tab, select the NETRADSENS, then click Change.
  14. Enter the sensitivity from the calibration sheet.
  15. In this example, the sensitivity is 12.3 μV/W m-2. Then click OK.

Retrieving Data

If the system is configured to log biomet data in .ghg files for processing in EddyPro software or the SmartFlux System, data are stored on the removable USB storage device. Refer to the Biomet Instruction Manual for details.


  • Keep sensor clean using water or alcohol.
  • Keep instrument level.
  • Recalibrate sensor every 2 years. Contact the manufacturer for more information.