Decentralized Process Management (SAP Library - Process Management (PP-PI-PMA))

Decentralized Process Management

Purpose

Decentralized process management is mainly suitable for plants that are closely integrated with the functions of the process control level and therefore require high system availability.

This component enables decoupled process management in a decentralized SAP R/3 System. This means that an additional SAP R/3 System that only contains data for production execution is installed at the plant level. By decoupling this system from the central, corporate SAP R/3 System, the availability of functions closely related to production can be guaranteed much easier. When the central SAP R/3 System is unavailable, for example, due to a release upgrade, production can still be executed.

Communication between the central and the decentralized SAP R/3 System takes place via the PI-PCS interface. You can link any number of decentralized SAP R/3 Systems to a central SAP R/3 System. Through the control recipe destination, you define in which decentralized system production is to be executed.

This graphic is explained in the accompanying text

Prerequisites

You have made the relevant Customizing settings in the central and in the decentralized SAP R/3 System.
For more information, see:

Customizing Settings in the Central SAP R/3 System

Customizing Settings in the Decentralized SAP R/3 System

Process Flow

The following process describes the standard scenario for using decentralized process management:

You create process orders in the central SAP R/3 System and release them.

See also: Creating Process Orders

After process order release, the central system automatically creates the control recipes and sends them to the decentralized system using a background job.

The control recipe is created with a new number in the decentralized system. This control recipe first has status To be sent and is processed in the decentralized system according to the definition of the control recipe destination.

See also: Sending of Control Recipes

In the decentralized system, the control recipes are:

Converted to a PI sheet
Forwarded to an external process control system

Control recipes that:

Were converted to PI sheets are maintained in the decentralized system. You enter actual data in the PI sheet.

See also: PI Sheets

Were sent to external systems are processed there.

See also: PI-PCS-Interface

When the control recipes have been processed, the decentralized system creates process messages from the actual data and:

Sends them to the central system
Processes them locally in the decentralized system

If the control recipes are sent to the central system, you must make sure that they have the same status in the central and in the decentralized system.

As before, the decentralized system also creates a process message of category PI_CRST that sets the control recipe status Completed in the decentralized system. The status of the control recipe must now also be updated in the central system and the corresponding status must be set in the process order. However, the standard message category PI_CRST only contains the number of the control recipe in the decentralized system but not the number of the control recipe in the central system.

For this reason, you must have carried out the IMG activity Transport Predefined Message Categories to Decentralized SAP R/3 System in the decentralized system. Special message categories and destinations that correctly update the status of control recipes in the central and in the decentralized system are copied.

In the decentralized system, message category PI_CRST also comprises the message destination PI18 that contains the order number and control recipe destination. Message destination PI18 creates a message of category PI_CRST2 into which the order number and the control recipe destination are written. This PI-CRST2 message containing the current control recipe status is sent to the central SAP R/3 System.

The central system receives the current control recipe status through the PI-CRST2 message. It must, however, determine the corresponding control recipe number.

For this reason, you must have carried out the IMG activity Transport Predefined Message Categories to Central SAP R/3 System in the central system. Message category PI_CRST2 and message destination PI17 are copied.

The process message of category PI_CRST2 from the decentralized system is processed by the message destination PI17: Ctrl recipe confirmat. via order number. Message destination PI17 uses the order number and the control recipe destination to determine the number of the control recipe destination in the central system and sets the corresponding status in the control recipe and process order.

Result

Processing in the Central System

Process messages that are sent to the central system serve to update stocks and the order status there. This ensures data integration in the central SAP R/3 System.

Processing in the Decentralized System

Process messages that remain in the decentralized system can be stored there for future analyses or sent to an external system for evaluations.