Campbell CR1000X, Руководство по эксплуатации продукта

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sample rate
The rate at which measurements are made by the datalogger. The measurement sample
rate is of interest when considering the effect of time skew, or how close in time are a
series of measurements, or how close a time stamp on a measurement is to the true time
the phenomenon being measured occurred. A 'maximum sample rate' is the rate at which
a measurement can repeatedly be made by a single CRBasic instruction. Sample rate is
how often an instrument reports a result at its output; frequency response is how well an
instrument responds to fast fluctuations on its input. By way of example, sampling a large
ga
u
ge thermocouple at 1 kHz will give a high sample rate but does not ensure the meas-
urement has a high frequency response. A fine-wire thermocouple, which changes out-
put quickly with changes in temperature, is more likely to have a high frequency
response.
SCADA
Supervisory Control And Data Acquisition
scan interval
The time interval between initiating each execution of a given Scan() of a CRBasic pro-
gram. If the Scan() Interval is evenly divisible into 24 hours (86,400 seconds), it is syn-
chronized with the 24 hour clock, so that the program is executed at midnight and every
Scan() Interval thereafter. The program is executed for the first time at the first occurrence
of the Scan() Interval after compilation. If the Scan() Interval does not divide evenly into
24 hours, execution will start on the first even second after compilation.
scan time
When time functions are run inside the Scan() / NextScan construct, time stamps are
based on when the scan was started according to the datalogger clock. Resolution of
scan time is equal to the length of the scan.
SDI-12
Serial Data Interface at 1200 baud. Communication protocol for transferring data
between the datalogger and SDI-12 compatible smart sensors.
Appendix A. Glossary 204