Sutron 8800-1205, Operation & Maintenance Manual

Page: 6 / 18

Sutron Corporation SDI ‐ TB Users Manual Rev. 1.1 5/24/2018 pg. 6
Fig: Charging current vs Time
The internal RTC and Tipping bucket interfaces are fully functional while running off the backup power
source. However, the SDI ‐ 12 interface is disabled while running off backup power. The SDI ‐ 12 interface
functionality is automatically restored when SDI ‐ 12 power is restored.
The SDI ‐ TB is fully compliant with the SDI protocol v1.3 The ‘D0’ command issued after an ‘M’ command
returns various accumulations and counter values.
For eg
Command = aM!
Response = a0005
Command = aD0
Response = a+< acc_last >+< raw_ tip_year >+< acc_year >+< acc_daily >+< acc_yest >
< acc_last > = total accumulations since the last M command was issued. Every time an M
command is issued, this parameter will be reset.
< raw_ tip_year > = The SDI ‐ TB can be programmed to reset its annual counters/accumulation at
the start of a rain year. This parameter returns the total raw tip counts for the current rain ‐ year .
< acc_year > = This parameter returns the total rainfall for the current rain ‐ year .
< acc_daily > = The SDI ‐ TB can be programmed to reset the daily rainfall value once every day.
This parameter returns the total rainfall today.
< acc_yest > = This parameter returns the total accumulation yesterday. Each time the daily
accumulation is reset by the daily timer, the total accumulation today is saved as yesterday’s
accumulation.