Alarm Type - ABB COMMANDER 1900 Series Programming Manual

...3.4 Set Up Alarms
tYPE
S–rAtE
F–rAtE
SELECt
LO–PrC
HI–PrC
OFF
OFF
trIP
––––––
HYSt
––––––
SELECt
t–HYSt
––––––

Alarm Type

Select the alarm type required for the alarm selected.
HI–PrC – high process
LO–PrC – low process
F–rtE – fast rate (rate of change of process variable)
S–rtE – slow rate (rate of change of process variable)
OFF – alarm off
Trip Level
Set the trip value required for the alarm selected.
The following are displayed in engineering units:
HPrC, LPrC.
The following are displayed as a percentage of the engineering span (engineering range high –
engineering range low) per hour between ±0.5 and ±500%:
FrtE SrtE.
and
Hysteresis
Hysteresis is operational when the alarm is active.
Set the hysteresis value
engineering range) or in 0.1% increments for rate alarms. The alarm is activated at the trip level
but is only turned off after the alarm variable has moved into the safe region by an amount equal
to the hysteresis value. For rate alarms this setting is a percentage of the trip rate – see '
and ' SrtE ' in previous frame.
Time Hysteresis
Set the time hysteresis value required between 0 and 9999 seconds.
Note. The alarm condition must be present continually for the time set, before the alarm
becomes active. If a hysteresis level is also set, the alarm condition remains active until the
process variable moves outside the hysteresis band. When the alarm condition no longer exists
the alarm becomes inactive, i.e. time hysteresis does not affect turning off of alarm states.
Return to frame.
Select Alarm
3 BASIC CONFIGURATION LEVEL...
required for high/low process, in engineering units (within the
FrtE
'
13