Campbell Scientific CR9000X Measurement and Control System - Manual (Page 160)

Section 4. CRBasic – Native Language Programming
Settle Time, in microseconds, to delay between setting up a
measurement and taking the measurement reading. Will increase
the measurement time of each sensor by the amount of delay set.
Minimum delay for the 5000 mV and 1000 mV ranges is 10
microseconds, and the minimum delay for the 200 mV and 50 mV
ranges is 20 microseconds.
See Section 3.1.1.2 Delay for more information on Settle.
Integ The integration time in microseconds (10 microseconds
resolution) for the signal being measured. The datalogger will
repeat measurement samples every 10 microseconds throughout
the sampling interval (with the appropriate Delay at the beginning
and between RevDiff and RevEx if used) and output the average.
If a value of 100 is inserted into the integration parameter, then
the datalogger would take 10 A/D conversion samples. Each
sample will be separated from the previous sample by 10
microseconds. The resulting value, that is written to the Dest
parameter variable, will be the average of the 10 samples.
The random noise level is decreased by the square root of the
number of measurements made. For example, the input noise on
the
±5000 mV range with no integration (one measurement) is 90
μV RMS; integrating for 40 μs (four measurements) will cut this
noise in half (90/(
√4)=45).
One of the most common sources of noise is not random but is 60
Hz from AC power lines. An integration time of 16,670
μs is
equal to one 60 Hz cycle. Integrating for one cycle will filter the
60 Hz AC noise to 0.
CR9058E has a 96 microsecond resolution and all channels on a
CR9058 module must have same integration.
See Section 3.1.1.3 Integration for information on Integration.
Mult/Offset The Mult and Offset parameters are each a constant (ex: 5 ),
variable (ex: mult ), array (ex: mult() ), or expression (ex: (5 +
mult) ) by which to scale the results of the measurement. The raw
output from the TCDiff instruction is in degrees Celsius. If other
engineering units than Celsius is desired, a multiplier and offset
other than 1 and 0 can be used.
If variable arrays are used for the multiplier and offset parameters
in measurements that use repetitions, the instruction will
automatically step through the multiplier and offset arrays as it
steps through the channels. This allows a single measurement
instruction to measure a series of individually calibrated sensors,
applying a unique calibration to each sensor.
The Mult() and Offset() variable arrays will need to be
dimensioned large enough to accommodate the number of Reps
specified for the measurement instruction.
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