Windows Automation Center, WinAC Slot Version 4.0
Hardware Installation and Operating Manual, Edition 02/2006, A5E00273194-02
45
3 Getting
Started
3.1
Definition of Terms
3.1.1
What Is a PC Station?
The PC station is a software-based virtual rack represented in the Station
Configuration Editor that is used for creating a PC-based automation system. Like
a hardware rack of an S7 CPU-based automation system, it contains space for
several modules required for the PC-based automation system.
When you install the WinAC Slot software, the controller appears by default in the
third slot (index) of this virtual rack in the Station Configuration Editor. The PC
Station is also represented in the STEP 7 Hardware Configuration editor.
3.1.1.1
Communication Model with S7-400
A PC-based controller is similar to an S7-400 hardware controller. The S7-400
controller consists of modules in a rack that communicate over the backplane bus
of the rack. Communications for an S7-400 are defined as follows:
•
STEP 7 communicates with the controller (in this example, an S7-400
CPU module) over an MPI subnet, using a CP card that is installed in the
computer.
•
The controller communicates with expansion modules over the backplane bus
of the rack.
•
The S7-400 CPU communicates with distributed I/O over a PROFIBUS DP
subnet using a built-in submodule interface or an IF module.
