Selecting PCS 7 Project Wizard Architecture for Redundant OS Single Stations with Mobile ES

When using the SIMATIC PCS 7 New Project Wizard to create a system comprising two redundant, synchronized operator stations and one portable laptop Engineering Station (ES) communicating with an S7-400H controller, neither the 'Single station system' nor the 'Multiple station system' wizard option matches the required topology directly. The correct procedure is to select 'Single station system' in the wizard to generate the base controller, plant hierarchy, and initial OS station, and then manually insert a second SIMATIC PC Station in Component View, configure it as an OS Single Station, and link them as a redundant pair using the OS Redundancy configuration editor.

Executive Summary

Starting a new distributed control system project in SIMATIC PCS 7 begins with the 'New Project Wizard'. For a common industrial architecture consisting of two identical, synchronous operator stations and a mobile laptop Engineering Station connected to a redundant S7-400H automation controller, engineers frequently hesitate at the wizard selection dialog: 'Single station system' or 'Multiple station system'. Selecting 'Single station system' creates only one operator station, whereas selecting 'Multiple station system' creates a client-server structure (OS Server + OS Client) that does not match a redundant single station topology. This article clarifies the architectural models generated by the PCS 7 wizard and provides the step-by-step procedure to establish a redundant OS Single Station project with a mobile engineering station.

Architecture and Fundamental Mechanics

PCS 7 New Project Wizard Models, PC Station Types, and Mobile ES Integration Mechanics:

Analysis of the PCS 7 Wizard System Options:
Option 1: Single Station System:
- Generates one S7-400 AS station and exactly one SIMATIC PC Station containing a WinCC Application and an OS object.
- This represents a non-redundant, single-PC operator console.
Option 2: Multiple Station System:
- Generates one S7-400 AS station, one SIMATIC PC Station with a WinCC Application (Server), and a second SIMATIC PC Station with a WinCC Application (Client).
- This represents a traditional distributed Client-Server topology.
The Engineering Gap: The wizard contains NO pre-built option called 'Redundant OS Single Station'. Consequently, attempting to configure this architecture entirely from the wizard dialog is impossible.
The Target Topology: Redundant OS Single Stations + Mobile ES:
OS Single Station 1 & 2: Two standalone PC stations. Each station runs an identical WinCC runtime project, connects directly to the S7-400H Plant Bus, provides independent operator control, and synchronizes archives via WinCC Redundancy.
Mobile Laptop ES: The engineering laptop does not host runtime operator visualization. It hosts the SIMATIC Manager multiproject, compiles CFC/SFC and OS, and downloads changes to the controller and the two operator stations over the network.
Recommended Wizard Workflow:
Choosing 'Single station system' in the wizard is the optimal starting point because it creates the S7-400H hardware configuration, master data library, and first WinCC Application.
The engineer then manually clones or inserts the second PC station in SIMATIC Manager and establishes the redundancy partnership.

Step-by-Step Implementation Procedure

Execute the 'New Project Wizard' with Base Settings:
* Launch SIMATIC Manager on the engineering laptop.
* Select File -> 'New Project' Wizard....
* Under CPU selection, select the redundant CPU (e.g. CPU 410-5H or CPU 414-5H / 417-5H).
* Under Plant Hierarchy, specify the number of hierarchy levels.
* Under System Options, select Single station system.
* Complete the wizard to generate the multiproject.
Add the Second PC Station in Component View:
* In SIMATIC Manager, switch to Component View.
* Right-click the project node -> Insert New Object -> SIMATIC PC Station.
* Name the stations: OS_Single_1 (from wizard) and OS_Single_2 (newly added).
Configure Hardware for Both PC Stations:
* Open HW Config for OS_Single_2.
* From the Hardware Catalog, insert the communications processor (e.g. CP 1623 or IE General) into Slot 1.
* Insert WinCC Application into Slot 2.
* Save and compile hardware configuration for both stations.
Link the Stations as Redundant Partners:
* In SIMATIC Manager, select OS_Single_1.
* Right-click the OS project object -> Object Properties.
* Navigate to the Redundancy (or Target OS and Standby OS) tab.
* Assign OS_Single_2 as the Standby / Redundant partner station.
* Open WinCC Explorer on OS_Single_1, open the Redundancy editor, enable redundancy, and select the redundancy network path.
Configure the Mobile Laptop Engineering Station (ES):
* The laptop is configured as the Engineering Station.
* In Windows, set the network adapter connected to the plant to match the subnet of the Terminal Bus and Plant Bus.
* In SIMATIC Manager, use PLC -> Set PG/PC Interface to bind to the laptop's Ethernet card (e.g. TCP/IP(Auto) -> Network Card).

Verification

In SIMATIC Manager, execute Compile OS; verify that both OS_Single_1 and OS_Single_2 are listed and compiled synchronously.
Download OS_Single_1 and OS_Single_2 to their respective physical PC stations over the network.
Start WinCC Runtime on both stations; verify that both PCs display the full process graphic tree.
Verify in WinCC Explorer that @RedundancyState reads 1 on Station 1 and 2 on Station 2.
Change a setpoint on Station 1; confirm that the controller updates immediately and reflects the change on Station 2.

Limitations and Operational Precautions

Selecting 'Multiple station system' in the wizard by mistake creates an OS Client project for the second station, which cannot be converted to an OS Single Station without deleting the client application and re-inserting a standard WinCC application. Ensure that the mobile laptop ES is assigned a fixed IP address on the engineering/terminal subnet to avoid download interruptions.

Engineer FAQ

Which wizard option creates a redundant OS Single Station pair?

Neither option creates this pair directly. Select 'Single station system' and manually add the second PC station in Component View.

What is the difference between Single station system and Multiple station system in the wizard?

'Single station system' creates one standalone OS, while 'Multiple station system' creates one OS Server and one OS Client.

Can an engineering laptop act as an operator station in this setup?

No, the mobile laptop acts strictly as the Engineering Station (ES) for programming and downloading, while the two desktop PCs act as operator stations.

What WinCC application type is inserted in HW Config for redundant single stations?

A standard 'WinCC Application' is inserted in both stations; the redundant link is established in SIMATIC Manager and the WinCC Redundancy editor.

Can clients be added to this configuration in the future?

No. OS Clients cannot connect to Single Stations. Adding clients in the future requires migrating the project to an OS Server Redundancy architecture.