Campbell Scientific CNR1 Net Radiometer - Manual (Page 15)

CNR1 Net Radiometer
TABLE 5-3. CR3000 and CR5000 Connections
for Differential Measurement
Function Color CR3000/CR5000
CM3 Up Signal Red Differential Input (H)
CM3 Up Reference Blue Differential Input (L)
CM3 Down Signal White Differential Input (H)
CM3 Down Reference Black Differential Input (L)
CG3 Up Signal Grey or Orange Differential Input (H)
CG3 Up Reference Yellow Differential Input (L)
CG3 Down Signal Brown Differential Input (H)
CG3 Down Reference Green Differential Input (L)
PT-100 Signal + Yellow Differential Input (H)
PT-100 Signal - Green Differential Input (L)
PT-100 Current Excitation + Red Current Excitation IX
PT-100 Current Excitation - Blue Current Excitation IXR
Shield Clear
6. Datalogger Programming
The CNR1 outputs four voltages that typically range from 0 to 15 mV for the
CM3 sensors, and
± 5 mV for the CG3 sensors. A differential voltage
measurement (VoltDiff or Instruction 2) is recommended because it has better
noise rejection than a single-ended measurement. If differential channels are
not available, single-ended measurements (VoltSe or Instruction 1) can be
used. The acceptability of a single-ended measurement can be determined by
simply comparing the results of single-ended and differential measurements
made under the same conditions.
For the CR3000 and CR5000, one differential channel and a current excitation
channel are required to measure the PT-100.
For the other dataloggers, two differential channels and the 4WPB100 module
are required to measure the Pt-100 temperature sensor.
The 4WPB100 is included with the CNR1 sensor purchased from
CSI. NOTE
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