Trend Log - Siemens SITRANS P Operating Instructions Manual

Lower limit with hysteresis (B)
An underrun event is counted when the process value falls below the lower limit
The next underrun event is counted when the process value first rises above the lower limit plus
the entered hysteresis
Within 'B', two events are counted in the displayed period.
Limits without hysteresis
If you enter the value "zero" in the "Hysteresis" text box, the hysteresis is disabled.
Upper limit without hysteresis (C)
An overrun event is counted when the process value rises above the upper limit
The next overrun event is counted when the process value falls below the upper limit
value, and then rises above the upper limit
Within 'C', three events are counted in the displayed period.
Lower limit without hysteresis (D)
An underrun event is counted when the process value falls below the lower limit
value.
If the process value falls below the lower limit by any value
counted again.
Two events are counted in the displayed period within 'D'.
See also
Configuring limit monitoring (Page 154)
9.3.8.2

Trend log

Set trend log
1. Select the menu command "Device > Trend log settings".
2. Define the number of process values you wish to log.
3. Use the "Logging behavior" parameter to define the buffer behavior.
– To fill the buffer with a variable number of logging points between 1 to 735 per process
– If you select the buffer behavior "Overwrite", the buffer is completely deleted. After the
4. In the "Logging interval" parameter, enter the interval in seconds between the logging points.
SITRANS P320/P420 with 4 to 20 mA/HART
Operating Instructions, 11/2019, A5E44852162-AC
②
, and then falls below the lower limit
value, select "Fill and stop".
The buffer is deleted and filled up to the number of set logging points. Then logging is
stopped.
buffer size of 735 logging points per process value has been reached, the 15 oldest
logging points are cyclically replaced with 15 new logging points.
9.3 Parameter assignment over remote operation
③
.
②
.
②
, the next underrun event is
Parameter assignment
①
.
①
.
②
by any
①
by any
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