Setup guide

OSx Migration Cookbook August 30, 2006
11 – Action Requests
Fast action
requests
Action request
annunciation and
acknowledgement
their names are unique.
In OSx properly configured action requests are reported by the PLC
because trigger tags are configured as RBE tags. This means that
action requests can be triggered and reset faster than once per
second. OSx will see these action requests and operators will still
have to respond.
In PCS 7 the server scans for action request trigger tags and the
scan cycle is no faster than once per second. That means that action
requests that are triggered and reset within the same PCS 7 scan
cycle may be missed. This is because, unless you configured them
as such, action request trigger tags are not automatically treated as
alarm tags whose data is communicated via RBE. If you do
configure trigger tags as alarm tags you may get an alarm and alarm
message in addition to an action request. Appendix C has a
procedure that shows how to configure trigger tags as alarm tags so
that they get the benefit of RBE, without producing alarms and
alarm messages in PCS 7. There is a companion DBA project
available that illustrates the procedure.
As discussed in the section on the Plant Hierarchy, there is no
action request summary. Action requests are annunciated in a
manner similar to alarms using the alarm group display. From the
alarm summary one can travel to the page on which the symbol for
that action request is located, open its faceplate and answer or
acknowledge it.
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