By connecting an ERP system such as SAP, it becomes possible to map all business processes within a company. That has the advantage that the OT and IT levels, i.e. the operational and business worlds, converge. In addition, all resources available in the company are managed. However, a detailed view of specific processes is often difficult under SAP, which in practice often requires the use of additional third-party software solutions.
In the context of digitalization, there is dynamic competition with constantly increasing requirements. To remain competitive in this environment, the functional scope of the SAP ERP system is often insufficient, as it is only focused on the business and does not consider the operational requirements of the field level (OT).
Heterogeneous system landscape
The industrial system landscape has grown considerably over the years and has become increasingly heterogeneous, resulting in greater complexity and an enormous support effort. The consequence is that it is challenging to integrate SAP ERP into existing operations (OT) systems, which ultimately drives a Smart Manufacturing initiative.
The changeover to individualized products, especially in the manufacturing industry, involves a great amount of effort for production planning, set-up times and controlling. Complexity is not only involved in the changeover to the production of individualized products, but also in general changes at short notice, such as changes to the delivery date or the order quantity. Particularly in the case of changes to the general conditions after the production order has been released, cumbersome processes arise.
Central point of contact
Due to the increasing heterogeneous system landscape already mentioned, there is often a lack of a central point where all valuable information converges. Inventory, machine performance, consumption and quality data, for example, must be taken from the individual systems. Collecting the information in this way results in a great deal of work for companies as well as a high susceptibility to errors, which can lead to a lack of an overall view of important production data.
Digitalization enables costs to be saved by networking and automating production. The SAP system in the production environment offers various options for automating store floor data collection. However, it has not yet been possible to consolidate the data from different store floor systems and use it interactively. That leads to a lack of IIoT capability at the store floor level.
Standard MES function
SAP is an ERP system and therefore suited for resource planning. However, when it comes to detailed order planning, there is no in-house solution from SAP. So, there is a lack of capable standard MES functions. As a result, it is impossible to receive notifications such as error messages from production and operation systems without the use of third-party software. Flexibility, traceability, and transparency in manufacturing are essential due to advancing digitalization, increasing competitive pressure, growing demands on production and the increasing importance of Industry 4.0 and/or smart manufacturing initiatives.
SAP application in the production process via RFC
In the production process, automation devices must take over the steering of the production process at many points. Examples of criteria for this are releases, quality, storage capacities, line utilization, etc. For making these control decisions, the respective automation device must request the information from the system that possesses all the data, and often this is the SAP system. On the OT/production side, the use of OPC standards for data interchange between software applications and even hardware is generally accepted, and most OT systems have an OPC interface available. By using a third-party software solution that provides an OPC client and SAP connectivity, it is possible to connect the production data from your OPC Server to SAP. For example, a PLC can use this to trigger a synchronous RFC function call in SAP, transfer the input values and receive the instruction for the next step in the process as a return value. The execution as a synchronous RFC call is important for the production process since the result is immediately available allowing the next process step to be executed.
SAP application in production confirmation via IDoc
A lot of data accumulates in production that is required in the SAP system to carry out production planning. Production messages include data on finished goods, raw material, packaging and auxiliary material consumption or machine running times and statuses. The data can be used to plan raw material procurement, update inventories and schedule machine maintenance. Sending data automatically from the machine to the SAP system saves time, avoids manual data entry, and ensures more accurate and up-to-date data. Rather than a synchronous transfer via the RFC function, such messages could be sent to SAP as an IDoc. An IDoc is a message packet that is processed asynchronously. The production process is consequently not dependent on the processing of the data and can keep moving, while the IDoc handling process assures SAP receives the data because in SAP, the IDocs are then buffered in a queue and processed.