Configuring Multi-Server OS Clients and Unified Graphics Across Separate Multiprojects in PCS 7

In SIMATIC PCS 7, configuring a single OS Client to monitor two independent redundant OS Server pairs located in separate multiprojects requires importing server data packages (.pck) from both server systems into the client project. To display process objects from both servers within a single unified PDL picture, engineers utilize picture windows with explicit Server Prefixes or prefix tag names (ServerName::TagName), while ensuring identical PCS 7 versions and maintaining dedicated OS Client licenses.

Architecture of Multi-Server OS Client Configurations in PCS 7

In large process facilities partitioned into separate plants or independent multiprojects (e.g., Polymerization Unit in Multiproject A, Compounding Unit in Multiproject B), central control room operators frequently need a unified workstation:
* The Multi-Server Client: A single WinCC OS Client station configured to communicate simultaneously with multiple independent OS Server pairs across the terminal bus.
* Server Data Packages (.pck): Contain compiled tag dictionaries, alarm definitions, picture names, and archive structures exported from an OS Server.
* By importing server packages from both OS_Server_A and OS_Server_B, the client gains full visibility into tags and alarms across both plant sections.

Importing Server Packages (.pck) Across Distinct Multiprojects

When the server systems reside in separate multiprojects on separate Engineering Stations:
1. Generate Server Data on Both Systems:
* On Engineering Station A, execute an OS compilation for OS_Server_A and generate server data (Options -> OS -> Generate Server Data). This creates the package file <ServerName>.pck.
* On Engineering Station B, repeat the procedure for OS_Server_B.
2. Assign Client Location:
* Create the OS Client project within one of the multiprojects (e.g., Multiproject A).
* In SIMATIC Manager, assign OS_Server_A as the internal server.
3. Manually Load the External Server Package:
* Open the OS Client project in WinCC Explorer.
* Right-click Server Data and select Load....
* Browse across the network or transfer the package file from Engineering Station B (OS_Server_B.pck).
* Click Open. WinCC Explorer imports the second server package and registers its symbolic server prefix.
4. Configure Standard Server:
* In WinCC Explorer under Server Data, select Standard Server.
* Define which server handles default alarms and split-screen management (SSM) to ensure consistent operator toolbar navigation.

Design Patterns for Unified Graphics: Picture Windows vs. Server-Prefixed Tags

Operators often require monitoring interrelated equipment from both servers within the same visual graphic display:
* Pattern 1: Side-by-Side Picture Windows (Recommended):
* Create a host display (Main_Overview.pdl) on the client or primary server.
* Insert two Picture Window objects.
* In Window 1 properties, set ServerPrefix = "SERVER_A" and PictureName = "Unit_A_Mimic.pdl".
* In Window 2 properties, set ServerPrefix = "SERVER_B" and PictureName = "Unit_B_Mimic.pdl".
* This cleanly segregates graphic files while presenting a single seamless screen.
* Pattern 2: Interleaved Object Tags with Server Prefixing:
* To place block icons (e.g., motors, valves) from both servers onto a single continuous canvas, address the dynamic tags using the server prefix syntax:
text SERVER_A::MotL_FeedPump.Run SERVER_B::VlvL_Discharge.Opened
* Note that manual tag prefixing bypasses automated block icon generation; icons must be customized with explicit server identifiers.

Licensing and Multi-Server Operational Constraints

Configuring multi-server client architectures requires strict adherence to Siemens commercial licensing rules:
* OS Client Licensing: The physical client computer requires exactly 1 SIMATIC PCS 7 OS Client Runtime license registered in Automation License Manager (ALM). A single OS client license authorizes simultaneous connections to up to 18 OS server pairs.
* OS Server Redundancy: Each redundant server pair requires its own appropriate OS Server Redundancy software configuration. Do not assume a standard OS Server license is additive to OS Server Redundancy.
* Process Objects: Central AS RT Process Objects are consumed in their respective automation stations; displaying tags on the client does not consume additional AS POs.
* Version Parity: Both multiprojects and the client must operate on identical PCS 7 versions, service packs, and update levels (e.g., all systems on PCS 7 V9.1 SP2).

Verification

Launch WinCC runtime on the multi-server OS client workstation.
Open the unified process display: verify that picture windows or individual block icons from both Server A and Server B update with live dynamic values.
Click an APL motor icon belonging to Server A: verify that its faceplate opens and commands operate.
Click a valve icon belonging to Server B: verify that its faceplate opens and commands operate.
In the WinCC alarm banner, verify that alarms originating from both Server A and Server B populate chronologically with correct area tags.

Limitations and Operational Precautions

When updating charts or recompiling an OS on Server B, the updated server package (.pck) must be re-exported and re-imported into the client project to reflect new or modified tags.
Terminal bus network routing must permit bilateral communication between the client workstation and both redundant server pairs.
Disconnecting the network to Server B will cause objects associated with Server B to display gray disconnect markings while Server A continues running normally.

Engineer FAQ

How many OS server pairs can a single PCS 7 OS client connect to?
A single PCS 7 OS client can connect to up to 18 OS servers or redundant server pairs simultaneously.
What file contains the compiled tag and alarm dictionary of an OS server?
The server data package file with extension .pck (e.g., OS_SRV1.pck).
Does connecting an OS client to two servers require two client runtime licenses?
No, a single WinCC OS Client Runtime license authorizes connections to all supported servers.
What syntax accesses a tag from another server in a multi-server picture?
The syntax is <ServerPrefix>::<TagName> (e.g., SERVER_B::TIC_101.PV_Out#Value).
Can two multiprojects running different PCS 7 versions share an OS client?
No, all participating servers and clients must maintain identical PCS 7 and WinCC software versions.
What is the Standard Server setting in WinCC Server Data?
It defines which server processes un-prefixed tags, alarm logging operations, and user archive queries.
How do redundant OS server pairs appear in the client server package list?
The client imports a single package representing the redundant pair; WinCC Redundancy manages automatic switchover between partner servers.
What happens if a server package is not updated after adding new CFC blocks?
The client will be unable to resolve the new tags, displaying yellow exclamation marks or connection errors on the faceplates.
Can an OS client issue commands to controllers in both multiprojects?
Yes, commands initiated on the client pass through the respective OS server to the target Automation Station.
Where are imported server data packages stored in the client project?
In the OS client project directory under the Packages/ folder.

Technical References

SIMATIC PCS 7 OS Process Control System Operating Manual (V9.0 / V9.1)
SIMATIC HMI WinCC V7.5 Server-Client Configuration Manual
Siemens Industry Online Support Entry: Multi-Server Client Architecture in PCS 7 (Entry ID 299205)
SIMATIC PCS 7 Licenses and Configuration Limits Manual

Related Tags

PCS 7, WinCC, Multi-Server, OS Client, Server Data, Package, Server Prefix, Picture Window, Architecture, Redundancy

Configuring Multi-Server OS Clients and Unified Graphics Across Separate Multiprojects in PCS 7