Rockwell Automation FactoryTalk Metrics User Guide - Manual (Page 27)

Collecting Performance Data Chapter 3
FactoryTalk Metrics uses the OEE (Overall Equipment
Effectiveness) model to measure the performance of manufacturing
equipment. The OEE model yields a single performance rating for
every activity area (workcell, line, area, or plant) being monitored,
thereby providing a simple way to determine quickly if an activity
area is performing adequately. The OEE value can be used to assess a
single machine’s performance over time, or to compare the
performance of machines.
Three components contribute to the OEE value:
• Availability
The ratio of running time to available time.
Available time may be defined by a schedule, or modified by
planned downtime events such as preventive maintenance.
Available time may also be modified by events such as being
starved for parts or being blocked by a downstream process.
Availability = RunningTime / AvailableTime
• Throughput
The performance of a machine when it is running compared to
its ideal cycle time.
The ideal cycle time depends upon the product being
produced, and is measured in units of seconds per part.
Throughput = (TotalParts x IdealCycleTime) / RunningTime
• Quality
The percentage of good parts that are produced.
GoodParts = TotalParts – Scrap
Quality = GoodParts ⁄ TotalParts
The OEE calculation that is used by FactoryTalk Metrics is the
product of these three components:
OEE = Availability × Throughput × Quality
OEE Rating
Rockwell Automation Publication PLTMT-UM001M-EN-P-June 2014 27