A ClearSCADA system is used to transfer data between a Flow Computer Configuration Tool and three Flow Computers. In order to facilitate this, a VT Service Port Master is configured in the ClearSCADA database, along with three Virtual Terminals—one terminal for each outstation port (A, B, and C) that is being used to route the communications. Each Virtual Terminal Number configured in the database is used to uniquely identify one of the outstation ports.

The same ClearSCADA system is also used to transfer data between two DEC VT Terminals. In order to facilitate this, a second VT Service Port Master is configured in the ClearSCADA database, along with a fourth Virtual Terminal. This Virtual Terminal is for outstation port D—the port that is being used to route the communications to the DEC VT Terminal.

The ‘Master Port’ field on the Virtual Terminal Form is used to define which VT Service Port Master is associated with each Virtual Terminal.