Rockwell Automation FactoryTalk Metrics User Guide - Manual (Page 63)

Collecting Performance Data Chapter 3
6. Click Finish.
The formula is added to the Configure Performance
Parameters dialog box.
Availability is the ratio of running time to available time, and is a key
component of the OEE formula.
Availability = Running Time / Available Time
Available Time is also one of the three variables in the OEE
calculation itself:
OEE = (Good Part Count x Ideal Cycle Time) / Available Time
The calculation of Available Time is very important to get accurate
OEE data. The fundamental issue is to determine when a machine
(activity area) should be producing and when it should not. Some
companies count all shift time as available time, so any
non-productive time, no matter what the cause, is considered lost
capacity and reduces OEE. Others exclude some types of
non-productive time from the total available time, which results in
higher overall OEE values. This is not done to inflate OEE scores,
but to more accurately determine how efficiently the machine is
performing. Such exclusions can include:
Availability
Rockwell Automation Publication PLTMT-UM001M-EN-P-June 2014 63