Rockwell Automation FactoryTalk Metrics User Guide - Manual (Page 130)

Chapter 3 Collecting Performance Data
User-defined events can also be configured as Faults, for the
purposes of calculating Mean Time Between Failure (MTBF) and
other metrics. Considering only the Fault events as downtime is
another option for downtime reporting.
Reports of user-defined events can be created using the
PlantMetrics Event History report data source, with specific filters
applied so that only the data associated with the desired events or
event categories is displayed.
For more information, see "Report Data Sources (page 261)".
The disadvantage of this method of downtime tracking is the
possibility that at any point in time an activity area may not be
experiencing any user-defined event, or may be experiencing more
than one user-defined event. For example, a downtime event often
causes other events to occur, resulting in multiple events being active
at one time. This makes it difficult to account for all the time
accurately without implementing the non-overlapping event logic in
the control system.
Using machine states to track downtime allows you to configure a
state model for each activity area so that the whole time will be
attributed to a defined machine state. This will ensure that all the
time is accounted for in defined machine states, and no time is
double counted. The Machine State capability allows you to
prioritize the states in such a way that if there is more than one state
which theoretically could occur at the same time, then the state with
the highest priority becomes active. This prevents the problems
associated with a downtime event causing other events to occur.
To use machine states to track downtime:
1. Configure the machine states relevant to your activity areas.
Machine State
130 Rockwell Automation Publication PLTMT-UM001M-EN-P-June 2014