3.1.1 Alerts and Dead-band
A dead-band value can be defined, in order to avoid the
repetition of alerts that are based on limit
transgressions.
If the dead-band feature is activated, a value that has
triggered an alert will have to return towards its normal
state by the dead-band value, before a further alert can
be triggered.
In the example depicted above, the minimum
temperature is set to
15°C
. The dead-band is set to
5°C
.
An alert is triggered if the temperature falls below the
minimum temperature
(1)
. If the temperature falls
below this value again after having returned towards its
normal state by less than the value assigned to the
dead-band, no further alert is triggered
(2)
. The alert is
only re-triggered if the value has returned towards its
normal state by more than the value of the dead-band
(3)
and then falls back down below the minimum value
(4)
.
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