Signal processing
7.6 Trace function
SITRANS DA400 for material flow monitoring with protection against explosion
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Operating Instructions, 09/2007, A5E00841152-01
7.6
Trace function
Timer control
The effect of the parameter "P.13/TIME" and the function of the trace timers "A1-UP" and
"A1-T" are described below using the example of acoustic channel 1 and the main alarm
"P.6/AL1". The same function applies to all other channels, alarms (AL) and pre-alarms
(PrAL).
The "*-UP" timers can be used to identify a temporary violation, before the final alarm is
triggered. The "*-T" timers indicate how long the alarm has been responding for. This can be
used to derive a schedule for repairs.
Time 1
The measured value exceeds the alarm value and timer "A1-UP" begins
counting.
Time 2
The measured value falls below the alarm value hysteresis without the time
criterion "P.13/TIME" being reached. The timer "A1-UP" stops and retains its
value.
Time 3
As for time 1
Time 4
As for time 2
Time 5
As for time 1
Time 6
The time criterion "P13/TIME" is met. The alarm "AL1" is output. Timer "A1-
UP" retains its value. Timer "A1-T" starts to count the time.
Time 7
The measured value falls below the alarm value hysteresis and activates the
time criterion "P.13/TIME" again.
Time 8
The time "P13/TIME" has expired. The alarm is reset. Timer "A1-T" stops.
