3.2. Overview of measuring setup

The following figures show the principle of the measuring setup for the various measuring modes. Components and complete signals for gauges and automatic measuring devices used only for controlling the measurement are not displayed.

The measurement was performed under the following boundary conditions:

• The communication program in the S7 stations (if necessary) is called cyclically in OB1 of the S7 controller.
• For each S7 station precisely one S7 connection is established by the PC station (OPC server).
• Source/destination of the data in the S7 station are in the respective data blocks.
• Source/destination of the data in the OPC TestClient are in the respective memory of the PC
• The connection between the Test OPCClient and the gauge occur via an interruption capable PCI-IO PC card

Note

The systematic measuring error due to using the PCI-IO card for transmitting the trigger and ready signals to the gauge is a neglegtable variable here.

Measuring setup "monitoring variables"

Measuring setup "asynchronous reading/writing of variables"

Note

The measuring setup for the OPC modes "asynchronous writing" and "asynchronous reading" are principally the same.