SequenceManager events

SequenceManager
 events record status changes, processing actions, and user interactions as the
Equipment Sequence
 executes. These events have importance at runtime because they indicate the current status of various aspects of a manufacturing process and have historical importance because the data is a record of exactly what transpired.
The three event types recorded by the
SequenceManager
 are:
  • Sequence Command Events record commands to change state, change pause state, change sequence mode, change ownership, clear failures, change active step, override transition expression, and enable and disable sequence tag expressions.
  • Process Data Update Events record the value of system values updating, including the state, pause, mode, ownership, and failure.
  • Parameter Update Events record changes in value or status of sequence parameters and step tags, including operator updates to parameters and step tag values, operators changing the status of sequence parameter or step tag expressions, phase updates to step tag values, and phase requests for step tag data.
Keep these considerations in mind when using
SequenceManager
 events:
  • Equipment Phase
    s and
    Equipment Sequence
    s should be run in a periodic task.
  • Equipment Sequence
     programs can be in the same periodic task as the
    Equipment Phase
     programs, or in separate tasks.
  • Generating events affects the performance of an
    Equipment Sequence
    . Only generate events when records for executing the sequence are required.
  • Avoid generating more than 60 events and alarms combined per second.
  • Configure sets of sequence parameters and step tags to not exceed the memory capacity of the controller.
  • Equipment Phase
    s can execute faster than an
    Equipment Sequence
     can record events.
    An
    Equipment Sequence
     coordinates
    Equipment Phase
    s that run in fractions of a second. But, the firmware event generation systems cannot keep up. When it is important to reliably record events, it is best that the phase takes at least 10 seconds to run to completion.
  • When steps are started and completed, use automatic storing of input and output data. A phase executing PXRQ instructions to read input or write outputs from or to an
    Equipment Sequence
     faster than every 10 seconds may lose events.
    • 18 Steps with three parallel paths of simultaneous execution
    • 225 Parameters
    • Generating 334 events
    • For a sequence running 60 seconds
    • For an ES completing in approximately 60 seconds
      With this phase and sequence configuration, events are not lost when burst of alarms are processed.
      The benchmark is primarily for testing how fast
      Equipment Sequence
       can run without losing events. The execution speed of a sequence depends upon the execution speed of the
      Equipment Phase
      s. Phases that complete their execution in less than 10 seconds may lose events depending upon the number of alarms being generated.
The benchmark of a fast
Equipment Sequence
 program is tested as:
  • Equipment Phase
    s can be configured to get Input Parameters when they start and to store Output Parameters when they complete. This is the most efficient way to move data between an
    Equipment Sequence
    > and an
    Equipment Phase
    .
Provide Feedback
Have questions or feedback about this documentation? Please submit your feedback here.
Normal