Table 4.12
Simple horn parameters
Parameter
Default
Notes
Reset when new alarm
Not enabled
Minimum down time
0 s
No effect on the output.
Minimum up time
0 s
No effect on the output.
De-energise when all alarms are acknowledged
Not enabled
INFO
Acknowledging alarms (or not acknowledging alarms) has no effect on this horn output.
Simple horn example
Acknowledge
Alarm 1
Alarm 1
Alarm 2
Horn
(1)
(3)
(2)
Simple horn with acknowledge
The horn output is activated when one or more alarms are active.
The horn output is deactivated when all alarms are acknowledged, even if there are still active alarms. The horn output is also
deactivated when there are no active alarms.
Table 4.13
Simple horn with acknowledge parameters
Parameter
Default
Notes
Reset when new alarm
Not enabled
Minimum down time
0 s
No effect on the output.
Minimum up time
0 s
No effect on the output.
De-energise when all alarms are
acknowledged
Enabled
When all active alarms are acknowledged, the horn output is deactivated.
If there are no latched alarms, the horn output is also deactivated when all the
alarms do not exceed their set points, regardless of the acknowledgement
status of the alarms.
Simple horn with acknowledge example
DESIGNER'S HANDBOOK 4189340911K UK
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