Getting an Overview about Overall Equipment Effectiveness (OEE)

The Overall Equipment Effectiveness (OEE) is a central KPI in the manufacturing world. A simple solution built around this KPI can play an essential role in measuring the effectiveness of the production process and can be the baseline for the continuous improvement journey! Hence, OEE plays an important role in manufacturing performance management. A scalable OEE solution is not just about calculating KPI figures through some formulas but consists of comprehensive master data, transaction data, and analytic features. This unit introduces the OEE Calculation in SAP DM, demonstrates how to build the master data, and shows the out-of-the-box analytic features to drill down into the root cause of individual losses.

OEE as central KPI is calculated as the product of three components: Availability, Performance, and Quality. Here's a breakdown of each component and how they are calculated in SAP DM:

The Availability factor is calculated as the ratio of the time that a resource was actually productive to the time it was planned to be productive. This data can be collected either automatically through the change of a resource status via an API call, or manually by entering downtimes in the Production Operator Dashboard (POD).

Reason codes for downtimes can be tagged automatically through mapped "machine codes" or entered manually. Both scheduled and unscheduled downtimes are visible on the POD within the "Downtime" plugin. Within this plugin, downtimes can also be edited to adjust their duration or to assign reason codes.

If there are multiple Resources within a Work Center, the Resources can be defined in a hierarchy and certain Resources can be defined as bottlenecks. The effect of a bottleneck Resource is that if a child Resource is marked as such, downtimes are aggregated to the parent Resource as well.

The Performance factor measures how well production is going compared to the expected speed, called standard rate. This standard rate is the ideal speed under normal conditions. When production falls short of this standard rate, it is considered as Performance Loss.

Performance Loss is calculated for each shift by comparing the actual production speed to the standard rate. If no production is recorded during a period when production should and could occur, it counts as Performance Loss. The Performance Losses are shown in the POD within the "Speed Loss List" plugin. There, operators can assign reason codes to categorize the loss and can also split the loss into multiple reason codes if needed.

Quality measures the ratio of good quality products to the total number of products produced. This metric helps to determine the effectiveness of the production in generating products that meet quality standards.

Reason codes for quality can be logged during SFC scrapping or can be linked to Nonconformance Code (NC-Codes). So, if an SFC ends up as scrap via using NC, the linked reason code is logged as well.