Campbell CR1000X, Product Manual

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interval is 1 pulse per 10 seconds, which is 0.1 pulses per second. The resolution on a 100
millisecond interval is 10 pulses per second.
For example, if a flow sensor outputs 4.5 pulses per second and you use a 1 second scan, one
scan will have 4 pulses and the next 5 pulses. Scan to scan, the flow number will bounce back
and forth. If you did a 10 second scan (or saved a total to a 10 second table), you would get 45
pulses. The total is 45 pulses for every 10 seconds. An average will correctly show 4.5 pulses per
second. You wouldn't see the reading bounce on the longer time interval.
6.7 Vibrating wire measurements
The datalogger can measure vibrating wire sensors through vibrating-wire interface modules.
Vibrating wire sensors are the sensor of choice in many environmental and industrial applications
that need sensor stability over very long periods, such as years or even decades. A thermistor
included in most sensors can be measured to compensate for temperature errors.
6.7.1 VSPECT®
Measuring the resonant frequency by means of period averaging is the classic technique, but
Campbell Scientific has developed static and dynamic spectral-analysis techniques (VSPECT) that
produce superior noise rejection, higher resolution, diagnostic data, and, in the case of dynamic
VSPECT, measurements up to 333.3 Hz. For detailed information on VSPECT, see
Vibrating Wire
Spectral Analysis Technology .
6.8 Sequential and pipeline processing
modes
The datalogger has two processing modes: sequential mode and pipeline mode. In sequential
mode, datalogger tasks run more or less in sequence. In pipeline mode, datalogger tasks run
more or less in parallel. Mode information is included in a message returned by the datalogger,
which is displayed by software when the program is sent and compiled, and it is found in the
Status Table, CompileResults field. The CRBasic Editor pre-compiler returns a similar message.
The default mode of operation is pipeline mode. However, when the datalogger program is
compiled, the datalogger analyzes the program instructions and automatically determines which
mode to use. The datalogger can be forced to run in either mode by placing the
PipeLineMode
or
SequentialMode
instruction at the beginning of the program (before
the
BeginProg
instruction).
For additional information, visit the Campbell Scientific blog article, "Understanding CRBasic
Program Compile Modes: Sequential and Pipeline."
6. Measurements 78