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CS451/CS456 Submersible Pressure Transducer
17
There are three settings that can be changed: SDI-12 address, Pressure/Level
Units, and Temperature Units. Double-click on the window of the units to be
changed. This will open a pick menu box. Select the desired units and
Apply
the changes.
8.2 SDI-12 Commands
This section briefly describes using the SDI-12 commands. For
additional SDI-12 information, refer to Appendix
(p. D-1)
,
, or the videos
SDI-12 Sensors | Watch or Sniffer Mode
The CS451/CS456 supports the commands that are listed in TABLE
. When
using an
M!
command, the data logger waits for the time specified by the
sensor, sends the
D!
command, pauses its operation, and waits until either it
receives the data from the sensor or the sensor timeout expires. If the data
logger receives no response, it will send the command a total of three times,
with three retries for each attempt, or until a response is received. Because of
the delays this command requires, it is only recommended in measurement
scans of 10 seconds or more.
A
C!
command follows the same pattern as an
M!
command with the
exception that it does not require the data logger to pause its operation until the
values are ready. Rather, the data logger picks up the data with the
D!
command on the next pass through the program. Another measurement request
is then sent so that data are ready on the next scan.
TABLE 8-3. CS451/CS456 SDI-12 Commands
SDI-12 command
(
a
is the sensor address)
Values Returned or
Function
Units
a
M!
or
a
C!
1.
Pressure/Level
2.
Temperature
Configured Settings
a
M1!
or
a
C1!
1.
Pressure/Level
2.
Temperature
PSIG
°C
a
M2!
or
a
C2!
1.
Pressure/Level
2.
Temperature
PSIG
°F
a
M3!
or
a
C3!
1.
Pressure/Level
2.
Temperature
kPa
°C
a
M4!
or
a
C4!
1.
Pressure/Level
2.
Temperature
kPa
°F
a
M5!
or
a
C5!
Sensor Serial Number
NOTE