National Instruments BridgeVIEW - Manual (Page 143)

Chapter 5 Alarms and Events
BridgeVIEW User Manual 5-6 © National Instruments Corporation
How Do You Display Event History Information?
To read all the alarms and events in the BridgeVIEW system that have
occurred since the Engine was started (unless limited by buffer size) drop
the Event History Display from the Alarms and Events palette on your
front panel. Then, you can invoke the HMI G Wizard to create the diagram
code for an event history. You also can build your own diagram and use the
Read Event History VI in your block diagram. If you want to change the
default fields (time, date, tag name, alarm limit) that are visible in the Event
History Display, you can use the Event History Format control from the
Controls»Alarms and Events palette and change the checkbox selections.
You also can change the default colors of alarms, events, normal and
acknowledged alarms with the Color Codes for Event History control,
which also is available in the Alarms and Events palette.
You also can report the status of alarms currently in the system using the
output of either Read Alarm Summary VI or Read Event History VI, or by
using the Get Alarm Summary Status VI. This gives information on the
number of active alarms and unacknowledged alarms in the system. You
can use the Alarm Summary Status control available in the Alarms and
Events Controls palette to display this information on your HMI.
How Do You Acknowledge Alarms?
You can view the acknowledgment status of alarms in the Alarm Summary
or Event History Display. To acknowledge alarms currently in the system,
use the ACK button from the Controls»Boolean palette on the front panel
and the Acknowledge Alarms VI in the Functions»Alarms and Events
palette in the block diagram. Activity 5-2, Acknowledge Alarms in the
Alarm Summary Display, takes you through this process.
When you acknowledge these alarms, the acknowledgment status in the
Alarm Summary Display changes from
UNACK to ACK , and the color of the
text changes from red to yellow. These are the default colors, and you can
change them.
There are two modes for handling tags that were previously in alarm but
have returned to normal: Auto Acknowledge and User Must Acknowledge.
These modes are configured in the Tag Configuration Editor for each tag.
If a tag is configured for Auto Acknowledge, when the tag returns to
normal, the acknowledgment status automatically changes from
UNACK to
ACK . However, if it is configured for User Must Acknowledge, the status