Rockwell Automation FactoryTalk Historian SE 4.0 Live Data Interface User Guide - Manual (Page 32)

Chapter 5 Point Configuration
32 Rockwell Automation Publication HSELD-UM024A-EN-E–September 2013
EVENT='triggertagname' event_condition
where
triggertagname
is enclosed in single quotes and, if specified,
the
event_condition
immediately follows the
triggertagname
. If
the
event_condition
is not specified then it defaults to
Anychange
.
The update rate for event item groups is also related to the scan class,
so the server will be asked to update its cache once every scan period
for every event tag defined. This is probably faster or slower than
necessary. You must set the Loc4 attribute to make event tags work
well. The Location 5 attribute should have the value 1 for Event
tags.
Typical example:
Tag ExDesc Instrument Tag Loc1 Loc2 Loc3 Loc4 Loc5
PM1_Temp.PV EVENT='PM1_Trigger ItemID1 1 0 0 2 1
PM1_Rate.PV EVENT='PM1_Trigger ItemID2 1 0 0 3 1
In this case, PM1_Trigger are tags that are updated by this interface,
by another interface, or by manual entry. When a PM1_Trigger gets
a new event in the PI snapshot, the interface will send data for both
PM1_Temp.PV and PM1_Rate.PV to the PI server.