Specifications

Section 7. Measurement Instructions
Parameter
& Data Type
Enter
RevDiff Code Value
Result (Reversing requires twice as much time to complete)
Constant False 0
Signal is measured with the high side referenced to the low
True ≠0
A second measurement is made after reversing the inputs to
cancel offsets
SettlingTime
Constant
The time in microseconds to delay between setting up a measurement (switching to
the channel, setting the excitation) and making the measurement. (1 microsecond
resolution)
Entry
Voltage Range Integration Settling Time
0
All 250 µS 450 µS (default)
0
All _50Hz, _60 Hz 3 mS (default)
>=100
All All µS entered
Integ The time spent on integration in microseconds for each of the channels measured.
Constant Entry
Integration
250
250 µS
_60Hz or 16667
16,667 µS (reject 60 Hz noise)
_50 Hz or 20000
20,000 µS (reject 50 Hz noise)
Mult, Offset
Constant,
Variable,
Array, or
Expression
A multiplier and offset by which to scale the raw results of the measurement. See
the measurement description for the units of the raw result; a multiplier of one and an
offset of 0 are necessary to output in the raw units. For example, the TCDiff
instruction measures a thermocouple and outputs temperature in degrees C. A
multiplier of 1.8 and an offset of 32 will convert the temperature to degrees F.
CS7500 (Dest, Reps, SDMAddress, CS7500Cmd)
Communicates with the CS7500 open path CO
2
and H
2
O sensor. See CS7500
manual for more information.
Parameter
& Data Type
Enter
Dest
Variable or
Array
The Dest parameter is the input variable name in which to store the data from each
CS7500 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 CS7500
0 and 1
2
2
4
3
3
4
11
5
3
6
4
Reps
Constant or
Expression
The Reps parameter determines the number of CS7500 gas analyzers with which to
communicate using this instruction. The CS7500s must have sequential SDM
addresses if the Reps parameter is greater than 1
SDMAddress
Constant
The SDMAddress parameter defines the address of the CS7500 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 CS7500 that it communicates
with.
The SDM address is entered as a base 10 number, unlike older, jumper-settable SDM
instruments that used base 4.
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