Xylem H-3342 - Manual (Page 27)

H-3342
SDI-12 Command and Response Protocol 3-15
3.15 Extended Read Power_Mode and Write Power_Mode
The 4-20mA output is updated whenever a measurement is made. For industrial applications
where the H-3342 is connected to a SCADA or PLC system and low-power is not of concern, the
H-3342 can be programmed to make continuous measurements. This command is used to change
the power mode. The H-3342 comes from the factory with the power mode set to the Sleep mode.
Once a new value is written, a copy is sent to the sensor data buffer for verification. This data
can be viewed by using a subsequent "D" command. To read or verify the value any other time,
use the "XRPMD" command.
Command Response Description
"aXRPMD!" “a0011<cr><lf>" Read Power_Mode
"aXWPMDn!" “a0011<cr><lf>" Write Power_Mode
Where: a is the sensor address ("0-9", "A-Z", "a-z", "*", "?").
XRPMD are upper case characters.
XWPMD are upper case characters.
n is the new setting (0 or 1)
0 = Sleep between measurements
1 = Make continuous measurements (always on)
This command takes 001 seconds to complete and places 1 value in the data buffer. Use the
“aD0" command to collect and view the current value.
Example of a H-3342 Extended "Read Power_Mode" command:
Command Response Time Values Description
"aXRPMD!" "a0011<cr><lf>" 1 sec 1 Read Power_Mode
Command Response Description
"aD0!" "a+0<cr><lf>" Mode = Sleep
Example of a H-3342 Extended "Write Power_Mode" command:
Command Response Time Values Description
"aXWPMD1!" "a0011<cr><lf>" 1 sec 1 Write Power_Mode
Command Response Description
"aD0!" "a+1<cr><lf>" Mode = Always On