Q:  If an event is captured by multiple instruments downstream, how can we aggregate the events so that they are reported as only one event?



A: This can be done via “System Events.” As of right now, we do not support alarming off of system events, so there is not a way to send out just one email per system event using PQDMS. This is a feature that will be supported in the future, but it is not used by many of our customers, so it has been a lower priority.

PQView has the ability to prevent the sending of multiple email alerts if an event is detected by multiple instruments downstream. 
The Event Notification mechanism does have a “event period” feature that allows you to specify a period in which events from other monitors do not result in additional notifications. In the case of an event seen on multiple monitors a notification is sent for the first event downloaded; no additional message is sent for subsequent events that have timestamps within the “event period” signaled by the first event. In other words, the notification system can aggregate multiple messages into as single e-mail message.