Siemens SITRANS Series - Page 150

Configuring variables for monitoring
Configure a process value for each "Limit monitoring" tab. Select the process value to be
monitored in the "Monitored value" drop-down list. Enter the values for upper limit, lower limit
and hysteresis that trigger an event.
Limits
Each process value (monitored value) is assigned limits. The following limit parameters are
available:
● Upper limit
● Lower limit
● Hysteresis
Hysteresis
The hysteresis works as follows:
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A:Upper limit with hysteresis
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 lower limit minus hysteresis
(2), and then rises above the upper limit (3).
When hysteresis is enabled (value not equal to zero entered), two events are counted within
the time period specified by 'A'.
Parameter assignment
9.3 Parameter assignment over remote operation
SITRANS P320/P420 (mA/HART)
150 Operating Instructions, 06/2018, A5E44852162-AA