Campbell Scientific CR9000X Measurement and Control System - Manual (Page 242)

Section 7. Measurement Instructions
7-18
CS7500 (Dest, Reps, SDMAddres, CS7500Cmd)
Communicates with the LI7500 open path CO
2
and H
2
O sensor. See LI7500
manual for more information.
This instruction cannot be used in a SubScan.
Parameter
& Data Type Enter CS7500 PARAMETERS
Dest The Dest parameter is the input variable name in which to store the data
from each LI7500 associated with this instruction. The length of the input
variable array will depend on the number of Repetitions and on the selected
Command.
Command Input Variable Length per LI7500
0 and 1 2
2 4
3 3
4 11
5 3
Reps The Reps parameter determines the number of LI7500 gas analyzers with
which to communicate using this instruction. The LI7500s must have
sequential SDM addresses if the Reps parameter is greater than 1.
SDMAddres The SDMAddres parameter defines the address of the LI7500 with which to
communicate. Valid SDM addresses are 0 through 14. Address 15 is
reserved for the SDMTrigger instruction. If the Reps parameter is greater
than 1, the datalogger will increment the SDM address for each subsequent
LI7500 that it communicates with.
The SDM address is entered as a base 10 number, unlike older, jumper-
settable SDM instruments that used base 4.
CS7500Cmd The CS7500Cmd parameter requests the data to be retrieved from the
sensor. The command is sent first to the device specified by the
SDMAddress parameter. If the Reps parameter is greater than 1, subsequent
LI7500s will be issued the command with each rep. The results for the
command will be returned in the array specified by the Dest parameter. A
numeric code is entered to request the data:
Code Description
0 Get CO2 & H2O molar density (mmol/m3)
1 Get CO2 & H2O absorptance
2 Get internal pressure estimate (kPa), auxiliary measurement A,
auxiliary measurement B, and cooler voltage (V)
3 Get cell diagnostic value, output bandwidth (Hz), and
programmed delay [230 + (delay * 6.579)] (msec)
4 Get all data (CO2 molar density (mmol/m3), H2O molar density
(mmol/m3), CO2 absorptance, H2O absorptance, internal
pressure estimate (kPa), auxiliary measurement A, auxiliary
measurement B, cooler voltage (V), cell diagnostic value, output
bandwidth (Hz), and programmed delay [230 + (delay * 6.579)]
(msec))
5 Get CO2 & H2O molar density (mmol/m3) and internal
pressure estimate (kPa)
NOTE