Sutron Corporation X-Link Operations & Maintenance Manual, Rev 1.63 5/24/2016 pg. 124
12.2.
SDI Clock Synchronization
Certain Sutron SDI-12 sensors (such as the SDR, RLR, and the CF Bubbler) support
a command to set the time of the sensor via SDI-12. X-Link takes advantage of
that feature, and periodically sets the clock of the sensors using an SDI-12
command, ensuring that all devices share a common time.
When recording is enabled and every 24 hours thereafter, X-Link performs a
time sync with all the Sutron devices that support the XDT! command. Every
time sync is started by sending an I! command to every SDI-12 device that X-Link
has been set up to measure. If the device replies favorably to the I! command, an
XDT! command is issued to the device. X-Link then decides whether to sync that
device’s clock based on time validity, the presence of a GPS (either on X-Link or
on one of the attached devices), and the time difference between X-Link and the
device.
The XDT set time command takes the format aXDTYYYY/MM/DD HH:MM:SS!
a is address
XDT is the command to set the date and time
YYYY is the year
MM is the month (01 to 12)
DD is the day of the month (01 to 31)
HH is the hour (military time 0 to 23)
MM is the minutes
SS is the seconds
Example set date time command: 0XDT2008/06/26 13:15:00!
