ABB MicroSCADA Pro SYS 600 Technical Description page 17

1MRS751852-MUM
MicroSCADA Pro
System Overview
Technical Description
Alarm
Alarms are generated when something special has occured in the process. (An alarm
is prioritised in the event list.) Alarms can cause audio-visual alarms, changes in the
station picture, alarm pictures, alarm printouts and alarm lists. Information about
alarming objects is stored in the alarm buffer. The information remains in the buffer
until the reason for the alarm disappears or until the alarm is acknowledged.
The alarm list shows all the alarms that appear in the system alarm buffer. The alarm
list is divided into two different lists: one with persisting (active) alarms and one
with fleeting (inactive) alarms. An alarm is usually presented with a text that
explains the reason of the alarm. The information flow is shown in Figure 3.4.1.-2.
Alarms and events can be generated in three different ways:
• Process events can generate alarms. The state of the process is evaluated in the
base system, according to the limits that have been set. For example, if a
measured value exceeds the predefined limits, an alarm will occur.
• The system itself can generate internal alarms from diagnostic programs, which
supervise the MicroSCADA system components. An alarm will occur, if there are
system communication errors, e.g. if a printer error occurs.
• System alarms are generated by an external module. This module can be
considered as a system watch dog. System alarms of this type cannot be included
in the alarm list.
Other devices in the MicroSCADA system can also generate alarms.
SYS 600 *9.0
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