APS: Advanced Planning and Scheduling System; System Mission: Formulate and optimize production plans

MES: Manufacturing Execution System; System Mission: Execute production plans and manage production control

APS Advanced Planning and Scheduling System, like ERP Enterprise Resource Planning, belongs to the planning-level system, while MES Manufacturing Execution System belongs to the execution-level system. The two systems are independent yet complementary.

First, from a general understanding, the APS Advanced Planning and Scheduling System needs to obtain foundational data from the MES Manufacturing Execution System, but this is not necessarily the case. The foundational data for the APS Advanced Planning and Scheduling System, including material master data, BOM, routing, resources, production capacity, etc., can come from the ERP Enterprise Resource Planning system, the MES Manufacturing Execution System, or even be directly maintained and managed within the APS Advanced Planning and Scheduling System.

Additionally, some MES Manufacturing Execution Systems manage foundational data with very fine granularity, and such data can be used directly by the APS Advanced Planning and Scheduling System. However, in most enterprises, the data on resources, capacity, working calendars, routing versions, etc., managed in the MES Manufacturing Execution System, often does not meet the requirements of the APS Advanced Planning and Scheduling System, necessitating supplementary data management.

Secondly, to ensure the scheduling accuracy of the APS Advanced Planning and Scheduling System, it is often thought that production progress and inventory data must be obtained from the MES Manufacturing Execution System. This understanding is also incorrect. The sources of production progress and inventory data can be the MES Manufacturing Execution System, the ERP Enterprise Resource Planning system, or other production progress reporting tools such as the small-scale reporting system integrated within the APS Advanced Planning and Scheduling System.

In summary, if a manufacturing enterprise adopts both the APS Advanced Planning and Scheduling System and the MES Manufacturing Execution System in its system architecture, the two systems form a perfect combination. They can be used together or independently.