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Lower limit with hysteresis (B)
An underrun event is counted when the process value falls below the lower limit
①
.
The next underrun event is counted when the process value first rises above the lower limit plus
the entered hysteresis
②
, and then falls below the lower limit
③
.
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
①
.
The next overrun event is counted when the process value falls below the upper limit
②
by any
value, and then rises above the upper limit
②
.
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
①
by any
value.
If the process value falls below the lower limit by any value
②
, the next underrun event is
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
value, select "Fill and stop".
The buffer is deleted and filled up to the number of set logging points. Then logging is
stopped.
– If you select the buffer behavior "Overwrite", the buffer is completely deleted. After the
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.
4. In the "Logging interval" parameter, enter the interval in seconds between the logging points.
Parameter assignment
9.3 Parameter assignment over remote operation
SITRANS P320/P420 with 4 to 20 mA/HART
Operating Instructions, 11/2019, A5E44852162-AC
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Содержание SITRANS P
Страница 10: ...Table of contents SITRANS P320 P420 with 4 to 20 mA HART 10 Operating Instructions 11 2019 A5E44852162 AC ...
Страница 272: ...Abbreviations SITRANS P320 P420 with 4 to 20 mA HART 272 Operating Instructions 11 2019 A5E44852162 AC ...
Страница 280: ...Index SITRANS P320 P420 with 4 to 20 mA HART 280 Operating Instructions 11 2019 A5E44852162 AC ...