Specifications

HYDROLOGICAL SERVICES
DL3 100-016 IMP
Issue 2: 15/11/2005
Rainfall
Time
Interval
Rainfall
amount
Interval
Rainfall
amount
Trigger Alarm message
restart alarm
checking
RAl2 or RAl3 = Rainfall amount / Interval
= alarm event satisfied
Accumulated Rainfall Chart
Interval
Rainfall Alarm 2 and Rainfall Alarm 3 (RAl2 & RAl3)
RainfallAlarm 2 and 3 are rate of increase alarms. Alarm conditions for RAl2 and RAl3 are checked
after each rainfall event against the user defined criteria for rainfall amounts over some time interval.
Once conditions are satisfied, analarmsequence is generated sending the rainfallmessage. The alarm
event , RAl2 or RAl3, is then disabled for a period of time as defined by the interval duration of the
alarm parameter after which time alarm checking for the appropriate alarm condition continues. If
the alarm conditions RAl2 or RAl3 are re-defined by user command, then alarm checking
recommences immediately.
The rainfall alarm 2 and 3 can be individually disabled by entering RAL2= or RAL3= When the
alarm is disabled the alarm value is displayed as "--.-/--:--"
On-line Help
RAL2?
Rainfall Alarm 2: If the rainfall amount in the given time interval is exceeded
then an alm mesg is generated if alm checking is enabled
Syntax: RAL2<CR> Displays RAL2 value in inch/Hr:min
RAL2=0.79/02:30<CR> Sets RAL2 to 0.79" over last 2.5hrs
On-line Help
RAL3?
Rainfall Alarm 3: Same alarm criteria & syntax as RAL2