ABB SM1000 User Manual page 81

Videographic Recorder
SM1000
Trip Point
Process
Variable
High Annunciate Alarm Action
Fig. 4.14 High/Low Annunciate Alarms
Deviation exceeded –
fast rate alarm
becomes active,
slow rate alarm becomes
inactive, new period starts.
Deviation below limit
at end of time period –
slow rate alarm becomes
active, new period starts.
Deviation
Deviation
Fast Rate Alarm
Period
Alarm On
Alarm Off
Slow Rate Alarm
Alarm On
Alarm Off
Fig. 4.15 Fast-/Slow-Rate Alarms
IM/SM1000 Issue 11
Hysteresis
Alarm On
Alarm Off
Alarm acknowledged
by operator
Process
Variable
Hysteresis
Trip Point
Alarm On
Alarm acknowledged
Low Annunciate Alarm Action
Deviation below limit
at end of time period –
fast rate alarm
becomes inactive,
slow rate alarm
becomes active.
Deviation exceeded –
fast rate alarm becomes
active, slow rate alarm
becomes inactive,
new period starts.
4 Configuration
Alarm Off
by operator
Deviation below
limit at end of time
period – alarm
becomes inactive.
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