An alarm is a state changed in the process or control system that requires attention from
operators. The alarm is presented in an alarm list, often with a audible signal, and the
operator has to acknowledge the alarm before the audible signal disappears and the alarm is
removed from the list. Also the alarm state has to return before the alarm is removed.
An alarm consists of three events
- the alarm enters active state.
- the alarm state is returned from active to normal state.
- the alarm is acknowledged by an operator.
Priority
The priority of an alarm can be A, B, C or D, where A has the highest priority. The priorities
have different color marking. A alarm are indicated with red, B alarms with yellow, C alarms
with blue and D alarms with violet.
Type
There are seven different types of alarms the can be used to address alarms to different
categories of receivers.
Alarm
Ordinary alarm for plant operators.
MaintenanceAlarm
Alarm for maintenance personnel.
SystemAlarm
Alarms for system manager.
UserAlarm1-4
User defined alarm types.
The alarm type is matched with the EventSelectType in the OpPlace object, and the alarm list
will only display the selected alarm types.