March 2016
Reference Manual
000809-0100-4772, Rev FA
166
Masking alert conditions
Any combination of status signals can be masked. When a status signal is masked, it will not
be annunciated to the host system but will still be active in the device and viewable in the
device DD or DTM. The recommended action, FD_RECOMMEN_ACT will continue to show
the recommended action for the most severe condition or conditions detected as
determined by the status signal priority. This allows maintenance personnel to view and
correct device conditions without annunciating the conditions to operational staff. They are
masked using the following parameters:
1.
FD_FAIL_MASK to mask FD_FAIL_ACTIVE status signals
2. FD_OFFSPEC_MASK to mask FD_OFFSPEC_ACTIVE status signals
3. FD_MAINT_MASK to mask FD_MAINT_ACTIVE status signals
4. FD_CHECK_MASK to mask FD_CHECK_ACTIVE status signals
If a consolidated diagnostic condition is configured to annunciate in multiple status signal
categories it can be masked in one or several status signal categories, but left active and
annunciate in others. This provides significant flexibility but can lead to confusion when
responding to alerts. Generally alert conditions are assigned to only a single status signal.
Alert priorities
NE107 alerts can have any of 16 different condition priorities ranging from the lowest
priority of 0 to the highest priority of 15. This is done using the following parameters.
1.
FD_FAIL_PRI to specify the priority of FD_FAIL_ACTIVE status signals
2. FD_OFFSPEC_PRI to specify the priority FD_OFFSPEC_ACTIVE status signals
3. FD_MAINT_PRI to specify the priority FD_MAINT_ACTIVE status signals
4. FD_CHECK_PRI to specify the priority FD_CHECK_ACTIVE status signals
Note
F
OUNDATION
™
Fieldbus standards require that NE 107 alert priority is set to zero for all status
signals at manufacturing.
Zero priority behavior shows any active device diagnostics in the DD or DTM but alerts are
not generated based on the diagnostic conditions or published on the bus.
An alert priority of 2 or higher is required for every status signal category where status
signals are to be published on the bus.
Check with your host provider to determine the alarm priorities assigned to each status
signal category by your host. Manual configuration may be required.
DeltaV
™
assigns a priority of two or higher. The priority is based on status signal category.
The status signal priority determines the behavior of both real and simulated alerts.
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