Emerson Rosemount 3144P, Reference Manual

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154
Reference Manual
00809-0100-4021, Rev JA
Configuration
April 2017
Configuration
4.9.3 Filtering
Note
If damping has already been configured in the transducer block, setting a non-zero value for PV_FTIME
will add to that damping.
The filtering feature changes the response time of the device to smooth variations in output readings
caused by rapid changes in input. Adjust the filter time constant (in seconds) using the PV_FTIME
parameter. To disable the filter feature, set the filter time constant to zero.
4.9.4 Process alarms
Process alarm detection is based on the OUT value. Configure the alarm limits of the following standard
alarms:

High (HIGH_LIM)

High high (HIGH_HIGH_LIM)

Low (LOW_LIM)

Low low (LOW_LOW_LIM)
To avoid alarm chattering when the variable is oscillating around the alarm limit, an alarm hysteresis in
percent of the PV span can be set using the ALARM_HYS parameter. The priority of each alarm is set in
the following parameters:

HIGH_PRI

HIGH_HIGH_PRI

LOW_PRI

LOW_LOW_PRI
Alarm priority
Alarms are grouped into five levels of priority.
Priority
number
Priority description
0 The alarm condition is not used.
1 An alarm condition with a priority of 1 is recognized by the system, but is not reported to the operator.
2 An alarm condition with a priority of 2 is reported to the operator.
3–7 Alarm conditions of priority 3 to 7 are advisory alarms of increasing priority.
8–15 Alarm conditions of priority 8 to 15 are critical alarms of increasing priority.