Xylem H-4280 - Manual (Page 29)

H-4280
SDI-12 Command and Response Protocol 3-17
3.13 Extended Read Power_Mode and Write Power_Mode
The H-4280 has a precision +5Vref excitation output terminal for powering potentiometers,
thermistors and other sensors. The +5Vref output is normally turned off to save power while the
module is in its sleep mode and is switched on before a measurement is made. If desired, the
excitation output can be programmed to remain active while the module is asleep. Use the
“aXRPM!” and “aXWPM!” extended commands to monitor or change the status of the excitation
output while the module is in its sleep mode.
Once a new Power_Mode 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 "XRPM" command.
Command Response Description
"aXRPM!" “a0011"
Read Power_Mode
"aXWPMn!" “a0011" Write Power_Mode
Where: a is the sensor address ("0-9", "A-Z", "a-z", "*", "?").
XRPM are upper case characters.
XWPM are upper case characters.
n 0 = +5Vref is OFF during sleep
1 = +5Vref is ON during sleep
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-4280 Extended "Read Power_Mode" command:
Command Response Time Values Description
"aXRPM!" "a0011" 1 sec 1 Read Power_Mode
Command Response Description
"aD0!" "a+0" +5Vref is Off during sleep
Example of a H-4280 Extended "Write Power_Mode" command:
Command
Response Time Values Description
"aXWPM1!" "a0011" 1 sec 1 Write Power_Mode
Command Response Description
"aD0!" "a+1" +5Vref is On during sleep