Rockwell Automation FactoryTalk Report Expert User Guide - Manual (Page 55)

Understanding Report Templates Chapter 5
Rockwell Automation Publication RPTEXP-UM001H-EN-P-June 2014 55
Item Description
MTBF
(Mean Time Between
Failures)
MTBF = Uptime ⁄ FaultCount
Mean Time Between Failure (MTBF) is the ratio of running time to
the total number of failures. It measures the average amount of
time when a piece of equipment was in a running state between
failures. MTBF is a derived field that contains aggregate functions
and, as such, can only be used in summary report objects and
cannot have aggregate functions applied.
MTTR
(Mean Time To
Repair)
MTTR = FaultTime ⁄ FaultCount
Mean Time to Repair (MTTR) is the ratio of the time spent in a
failure state to the total number of failures. It measures the average
amount of time when a piece of equipment was in a failure state.
MTTR is a derived field that contains aggregate functions and, as
such, can only be used in summary report objects and cannot have
aggregate functions applied.
Faults per Hour Faults per Hour = Faults Count ⁄ Uptime
The average amount of faults per hour during the reporting period.
Fault % Fault % = FaultTime / Uptime
The percentage of time the machine spent in a fault state.
Detail Link to an Event Summary report referring to a specific fault,
filtered to display only faults and grouped by event name.
The values of the report template and other report templates to
which the values link using the drillthrough hierarchy:
Click a value in this column: To display this report template:
Running Time Fault (grouped by the next value in the
drillthrough hierarchy)
Fault Time
Fault Count
MTBF
MTTR
Faults per Hour
Fault %
Detail
Event Summary
The report template bar charts: MTBF and MTTR.