Campbell CR1000, Руководство оператора

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Section 11. Glossary
Term. ring memory
A memory configuration that allows the oldest data to be overwritten with the
newest data. This is the default setting for final-memory data tables.
Term. ringing
Oscillation of sensor output (voltage or current) that occurs when sensor
excitation causes parasitic capacitances and inductances to resonate.
Term. RMS
Root-mean square, or quadratic mean. A measure of the magnitude of wave
or other varying quantities around zero.
Term. router
Device configured as a router is able to forward PakBus packets from one
port to another. To perform its routing duties, a CR1000 configured as a
router maintains its own list of neighbors and sends this list to other routers in
the PakBus network. It also obtains and receives neighbor lists from other
routers.
Term. RS-232
R ecommended S tandard 232 . A loose standard defining how two computing
devices can communicate with each other. The implementation of RS-232 in
Campbell Scientific dataloggers to PC communications is quite rigid, but
transparent to most users. Features in the CR1000 that implement RS-232
communication with smart sensors are flexible.
Term. sample rate
The rate at which measurements are made by the CR1000. 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 gage thermocouple at 1 kHz
will give a high sample rate but does not ensure the measurement has a high
frequency response. A fine-wire thermocouple, which changes output
quickly with changes in temperature, is more likely to have a high frequency
response.
Term. scan interval
The time interval between initiating each execution of a given Scan() of a
CRBasic program. If the Scan() Interval is evenly divisible into 24 hours
(86,400 seconds), it is synchronized 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()
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