Campbell CNR1, Инструкция по эксплуатации

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CNR1 Net Radiometer
As a rule of thumb, for ambient temperatures of about 20 degrees Celsius, one
can say that one degree of temperature difference between two objects results
in a 5 Watts per square meter exchange of radiative energy (infinite objects):
1 degree of temperature difference = 5 Watts per square meter (rule of thumb)
4.7 Calculation of the Net (total) Radiation
In the 4 Separate Components Mode, Net radiation, NR, can be calculated
using the individual sensor measurement results:
NR = (E upper CM3) + (E upper CG3) -
(E lower CM3) - (E lower CG3) (4.8)
Where E is the irradiance that is calculated for the CM3 according to Equation
4.1, for the CG3 according to Equation 4.2, the terms with T cancel from this
equation.
5. Wiring
Figure 5-1 shows the CNR1 schematic with the four radiation outputs, Pt-100
temperature sensor, and the heater. The use of the heater is described in detail
in the Appendix B. All wiring schemes shown in this manual will show wiring
for both CNR1 and 4WPB100 modules. Wiring diagrams and Tables 5-1 and
5-2 are applicable only if you bought the CNR1 Net Radiometer from
Campbell Scientific, Inc.
Use of the CNR1 Net Radiometer, which you bought outside of Campbell
Scientific, is possible only on the CR3000 and CR5000 dataloggers. The
PT-100 can connect directly to the CR3000 and CR5000 because they have
current excitation inputs. Table 5-3 and Program Example 6.2.4 show wiring
and programming on the CR5000 datalogger without the 4WPB module.
All other CSI dataloggers require the 4WPB100 module to interface the
PT-100 to the datalogger.
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