All individual functions are performed in the R/3 System using RFC-enabled function modules (Remote Function Call). These function modules were first delivered with Release 3.0E.

The function modules for measurement documents and measuring points are able to return the complete object data to the calling application from Release 3.1. This is because the inclusion of floating point fields (Format FLTP) in the structures and tables of the RFC interfaces was not previously supported.

From Release 3.1I / 4.0B, you can use the following Customer Exits for measuring points and measurement documents:

• IMRC0001 runs before the update and enables you to define particular field contents in measurement points and measurement documents, to generate workflow events and to update customer-specific tables.

• IMRC0002 and IMRC0003 make available menu exits in the online processing of measuring points and measurement documents, so that you can trigger customer-specific functions or call up customer-defined screens.

You can also create the Customizing includes CI_IMPTT or CI_IMRG to extend the tables IMPTT (measuring point) or IMRG (measurement document) respectively, to include customer-defined fields. For each of the three mentioned Customer exits, you then maintain control of the customer-specific fields.

Because all individual functions can be called up using RFC, the calls can also be made by OLE (Object Linking and Embedding) (using SAP’s WDTFUNCS.OCX).

All function modules are online interfaces. In case the R/3 System is ever unavailable, the measurement values to be transferred in the process control system or in the SCADA system must be able to be buffered.