Use
Process messages are created by process control in order to report actual data on the execution of a process order.
Depending on the event to which it refers, a process message can be created in either of the following ways:Prerequisites
In both cases, the structure of the process messages must correspond to the predefined message category in R/3 Customizing.

You can create test messages to check the definition of your message categories and process instructions.
Within R/3, test messages are created and monitored in the same way as productive messages.
Features
Automatic Creation
If a process event is planned or expected, the corresponding message can be requested in a process instruction. In this case, the operator maintaining the PI sheet or the control system processing the control recipe has to provide the process data to be reported in the message. The message of the requested message category is created automatically.
For information on how to report process data in the PI sheet, see
Recording of Actual Process DataManual Creation
Process messages are created manually:
For a description on how to create process messages, see
Creating Process Messages Manually.