Technical Differences Between PLC Configure and PLC Download for PC Stations in SIMATIC Manager

In SIMATIC Manager, the commands 'PLC -> Configure' and 'PLC -> Download' perform distinct, non-interchangeable engineering functions for PC Stations (OS Servers, OS Clients, ES). 'PLC -> Configure' remotely provisions the physical computer's Station Configuration Editor (SCE), populating virtual rack slots with configured communication processors (CP 1623, CP 1613, IE General) and WinCC applications, assigning station names without transferring project data. In contrast, 'PLC -> Download' compiles and transfers the actual communication database (NetPro S7 connections, ISO/TCP routing) and the WinCC project runtime files to the configured station. If 'PLC -> Configure' fails despite successful network ping, verify that Simatic Shell selects the terminal bus adapter, Windows Firewall permits TCP ports 102/135 and DCOM, and the station name in HW Config matches the Windows computer name exactly.

Executive Summary

During the initial commissioning or hardware reconfiguration of SIMATIC PCS 7 PC Stations (such as an OS Server or Engineering Station), automation engineers frequently encounter communication failures when deploying settings from SIMATIC Manager. Right-clicking a PC Station object presents two critical commands under the 'PLC' menu: 'Configure' and 'Download'. Many engineers are uncertain of the technical boundary between these commands, often attempting 'Download' when 'Configure' is required, or failing to understand why 'Configure' cannot reach the remote PC even though standard network pings succeed. This guide provides a detailed technical comparison, analyzes the multi-IP plant bus vs terminal bus architecture, and resolves remote configuration failures.

Architecture and Fundamental Mechanics

The remote management architecture of SIMATIC PCS 7 PC Stations is divided into two distinct communication phases:
1. Station Hardware Provisioning (PLC -> Configure):
- Targets the Station Configuration Editor (SCE) running locally on the target PC (s7epatsx.exe).
- Communicates via DCOM and the Siemens remote configuration service over TCP port 135 and dynamic RPC ports.
- Function: Reconfigures the virtual backplane (Component Configurator). It inserts the communication processors (e.g., CP 1623 in Slot 1) and applications (e.g., WinCC Application in Slot 2) into the target PC's SCE, matching the station layout defined in HW Config.
- It does not transfer IP addresses or WinCC project databases; it configures the software containers to receive them.
2. Communication and Project Deployment (PLC -> Download):
- Once the SCE is configured, 'PLC -> Download' loads the compiled connection tables (.xdb file or S7 routing database from NetPro) into the communication processors via access point S7ONLINE.
- When executed on a WinCC application object, it copies the WinCC runtime project files across the terminal bus network share.
3. The Multi-IP / Plant Bus vs Terminal Bus Distinction:
- PCS 7 PC stations strictly require physical separation between:
a. Terminal Bus: Standard office/server LAN (TCP/IP) used for ES-to-OS engineering downloads, OS-to-client visualization, and Simatic Shell discovery.
b. Plant Bus: High-availability Industrial Ethernet (ISO transport or industrial TCP/IP) used for AS-to-OS communication via CP 1623.
- If the Engineering Station displays multiple IP addresses for the system bus, the engineer has either configured multiple logical IP aliases on the network card or bridged the plant and terminal buses, violating PCS 7 networking rules.

Step-by-Step Implementation Procedure

Verify Station Name and Network Identity:
a. On the target PC (e.g., OS Server), open Windows System Properties and record the exact Computer Name (e.g., OSS_SRV1).
b. In SIMATIC Manager on the ES, verify that the SIMATIC PC Station object is named identically to the Windows computer name (OSS_SRV1).
c. Confirm that the Windows user account on the ES exists on the target PC with identical password and belongs to the Administrators and SIMATIC HMI groups.
Configure Simatic Shell on ES and Target Station:
a. On both the ES and the target OS server, open Windows Explorer, right-click Simatic Shell, and select Settings....
b. Ensure that the selected network adapter is strictly the Terminal Bus network adapter.
c. Confirm that in Simatic Shell, the ES can see the OS Server, and the OS Server can see the ES.
Execute 'PLC -> Configure' on the PC Station:
a. In SIMATIC Manager, select the PC Station object (OSS_SRV1).
b. Select PLC -> Configure... from the main menu.
c. In the dialog, verify the target computer name matches and click 'Configure'.
d. When prompted to overwrite the Station Configuration Editor on the target PC, click 'Yes'.
e. Observe the SCE on the target PC: confirm virtual slots populate with the CP 1623 and WinCC Application.
Execute 'PLC -> Download' for Communication Connections:
a. With the PC Station selected in SIMATIC Manager, select PLC -> Download.
b. When prompted 'Do you want to download the configuration to the target station?', click 'Yes'.
c. This loads the NetPro S7 connection database into the Station Configuration Editor.
d. Verify that the SCE status on the target PC shifts to 'RUN' with green gear icons.
Download WinCC OS Project Data:
a. In SIMATIC Manager, right-click the WinCC Application object under the PC Station.
b. Select PLC -> Download.
c. Select the destination network share path on the target server and execute download.

Verification

On the target PC, open Station Configuration Editor: verify all modules display status 'OK' (pencil and gear icons without red crosses) and operating mode is 'RUN'.
In SIMATIC Manager, open NetPro: click the eyeglasses icon to go online and verify S7 connections to the AS controllers report status 'Established'.
On the target OS server, launch WinCC Explorer: confirm the project opens and connects to the runtime database.

Limitations and Operational Precautions

Executing 'PLC -> Configure' resets the Station Configuration Editor on the target PC. Never execute 'Configure' on an operational OS Server while the plant is actively running, as communication adapters will momentarily re-initialize.

Engineer FAQ

What does 'PLC -> Configure' do in SIMATIC Manager?

It remotely provisions the Station Configuration Editor (SCE) on the target PC, inserting virtual modules and applications to match HW Config.

What does 'PLC -> Download' do on a PC Station?

It transfers the compiled communication connection database (NetPro S7 connections) and WinCC project files to the configured station.

Why does 'PLC -> Configure' fail even when ping works?

Ping only verifies IP connectivity. 'Configure' requires DCOM permissions, Simatic Shell terminal bus binding, matching computer names, and unblocked RPC ports.