This button in the Bacnet Ws Device Manager retrieves event information from the selected device, requesting all outstanding events from the BACnet device. The purpose of this feature is that if Niagara somehow missed receiving an event, you can still retrieve and acknowledge this event using the Event Information service. For example, the Niagara station may not have been running at the time the original event occurred.

If the GetEventInformation service is supported, this will be used to retrieve events. The events retrieved in this manner contain enough information to generate a valid acknowledgment to the remote device. These event summaries will be propagated to the Niagara Alarm Service through the alarm class assigned in the eventSummaryAlarmClass property of the Event Handler.

Event Handler configuration is contained within the Server layer configuration, as shown in Figure B.2.

If the GetEventInformation service is not supported, but the GetAlarmSummary service is supported, the events will be retrieved using GetAlarmSummary. The GetAlarmSummary service retrieves only events with a Notify_Type of “alarm”, so events with a Notify_Type of “event” are not retrieved.

The GetAlarmSummary service has been deprecated by the BACnet Committee, and manufacturers should no longer be making devices that use it. Typically, this is seen only in older devices.

Event summaries retrieved using GetAlarmSummary do not have enough information to generate a valid acknowledgment, so they are not propagated to the Niagara Alarm Service. In this case, a dialog box is presented to the user, such as shown in Figure B.3.