Campbell Scientific CR6 CR6 Measurement and Control System - Page 507

Term. Seebeck effect

Page 507 highlights

Section 11. Glossary 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() Interval after compilation. If the Scan() Interval does not divide evenly into 24 hours, execution will start on the first even second after compilation. Term. 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 CR6 clock. Resolution of scan time is equal to the length of the scan. See system time (p. 510). Term. SDI-12 Serial Data Interface at 1200 bps. Communication protocol for transferring data between data recorders and sensors. Term. SDM Synchronous Device for Measurement. A processor-based peripheral device or sensor that communicates with the CR6 via hardwire over a short distance using a proprietary protocol. Term. Seebeck effect Induces microvolt level thermal electromotive forces (EMF) across junctions of dissimilar metals in the presence of temperature gradients. This is the principle behind thermocouple temperature measurement. It also causes small, correctable voltage offsets in CR6 measurement circuitry. Term. semaphore (measurement semaphore) In sequential mode, when the main scan executes, it locks the resources associated with measurements, i.e., it acquires the measurement semaphore. This is at the scan level, so all subscans within the scan (whether they make measurements or not), will lock out measurements from slow sequences (including the system background calibration). Locking measurement resources at the scan level gives non-interrupted measurement execution of the main scan. Term. send The Send button in datalogger support software (p. 89). The Send command sends a CRBasic program, or an operating system, to a CR6. 507

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Section 11.
Glossary
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()
Interval
after compilation. If the
Scan()
Interval
does not divide evenly into 24
hours, execution will start on the first even second after compilation.
Term. 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 CR6 clock.
Resolution of scan time is equal to the length of the scan.
See
system time
(p.
510).
Term. SDI-12
Serial Data Interface at 1200 bps. Communication protocol for transferring
data between data recorders and sensors.
Term. SDM
Synchronous Device for Measurement. A processor-based peripheral device
or sensor that communicates with the CR6 via hardwire over a short distance
using a proprietary protocol.
Term. Seebeck effect
Induces microvolt level thermal electromotive forces (EMF) across junctions
of dissimilar metals in the presence of temperature gradients. This is the
principle behind thermocouple temperature measurement. It also causes
small, correctable voltage offsets in CR6 measurement circuitry.
Term. semaphore (measurement semaphore)
In sequential mode, when the main scan executes, it locks the resources
associated with measurements, i.e., it acquires the measurement semaphore.
This is at the scan level, so all subscans within the scan (whether they make
measurements or not), will lock out measurements from slow sequences
(including the system background calibration). Locking measurement
resources at the scan level gives non-interrupted measurement execution of
the main scan.
Term. send
The
Send
button in
datalogger support software
(p. 89).
The
Send
command
sends a CRBasic program, or an operating system, to a CR6.
507