Troubleshooting AS/OS Compile Library Mismatches and Graphic Picture Misalignments in PCS 7 Upgrades

In SIMATIC PCS 7 upgrades (such as migrating from V8.0 to V9.0 SP3 across multi-engineering stations), AS/OS compilation failures stating that channel driver blocks do not match the installed library version occur when the project retains legacy PCS 7 Standard Library blocks (e.g., CH_AI, CH_DI) while the target ES only has the modern Advanced Process Library (APL) installed. To resolve this, either install the legacy migration library 'PCS 7 Standard Library V7.1 SP4' on the ES or modernize the logic using APL channel drivers (Pcs7AnIn, Pcs7DiIn). Discrepancies where graphic objects (like motor icons) appear displaced to the top-left corner on OS Clients but properly positioned on the OS Server stem from local graphic picture caching or uncompiled display resolution mismatches; resolving this requires downloading the complete OS project from the ES to the OS Server and re-downloading Server Data to the clients.

Executive Summary

Migrating large-scale SIMATIC PCS 7 multiprojects across major software generations (V8.0 to V9.0 SP3) frequently introduces hybrid engineering environments where two Engineering Stations (ES 1 and ES 2) access a shared network multiproject. When executing AS/OS compilations, engineers often encounter hard compile halts indicating driver library version mismatches. Concurrently, graphic visualization anomalies surface in runtime: equipment icons render at coordinate (0,0) in the upper-left corner on client workstations while displaying correctly on server consoles. Resolving these intertwined upgrade challenges requires installing the appropriate legacy compatibility libraries, synchronizing block signatures, and executing complete OS downloads to purge stale runtime picture caches.

Architecture and Fundamental Mechanics

The compilation and runtime visualization systems in SIMATIC PCS 7 rely on synchronized library schemas and graphic coordinates:

Driver Block Version Handshake During AS/OS Compile:
* When Generate module drivers executes during CFC compilation, the compiler parses all channel blocks against hardware description rule files (XML templates) in the Step 7 library directory.
* If a project originated in PCS 7 V7.x/V8.0 using legacy Standard Library blocks (CH_AI / FB 101, CH_DI / FB 102), the compiler searches for rule files from PCS 7 Basis Library V7.1 SP4.
* If the upgraded ES only has PCS 7 Basis Library V9.0 installed, the compiler cannot find matching legacy driver XMLs. It flags a library version mismatch and halts AS/OS compilation.
Multi-Engineering Station Network Access:
* When ES 2 accesses a multiproject hosted on ES 1 via Windows network shares, both engineering stations must have identical software packages, Hotfixes, and library versions installed.
* If ES 1 possesses the legacy migration libraries but ES 2 lacks them, compiling from ES 2 triggers driver generation failures.
Graphic Picture Misalignment on OS Clients:
* In WinCC, process graphic screens (.pdl) contain static objects and dynamic APL block icons (@MotL/1, @VlvL/1).
* Each block icon's position is governed by absolute coordinates (Left and Top) within the picture canvas.
* When a client workstation opens a picture, it caches local copies in the Windows temporary directory (WinCC\temp or GraCS cache). If the server picture was updated on the ES without downloading the updated picture files to the OS Server and re-generating Server Data, the client renders default uninitialized coordinates (Left = 0, Top = 0), stacking icons at the upper-left corner.

Step-by-Step Implementation Procedure

Follow these procedures to resolve compilation library errors and correct graphic displacement:

Identify the Channel Driver Library in Use:
* In SIMATIC Manager, open the S7 Program's Blocks folder.
* Inspect the installed channel drivers:
- If blocks are named CH_AI, CH_DI, CH_AO, CH_DO (FBs 101-104), the project relies on the PCS 7 Standard Library.
- If blocks are named Pcs7AnIn, Pcs7DiIn, Pcs7AnOu, Pcs7DiOu (FBs 1869-1872), the project uses the Advanced Process Library (APL).
Install Legacy Compatibility Library on All Engineering Stations:
* If legacy blocks (CH_*) are present, install SIMATIC PCS 7 Standard Library V7.1 SP4 (available on the PCS 7 V9.0 SP3 DVD under Additional Products or via Siemens Industry Online Support).
* Ensure this library is installed on both ES 1 and ES 2 to maintain multi-user engineering consistency.
Execute Clean AS Compilation:
* Open CFC on the master ES.
* Select Chart > Compile > Scope: Entire program.
* Ensure Generate module drivers is checked.
* Verify that compilation completes without library mismatch warnings.
Reconcile OS Graphics and Compile the OS:
* In SIMATIC Manager, right-click the OS object and select Compile.
* Compile Entire OS with 'Tags and messages' and 'Picture Tree'.
* Open the OS project on the ES in WinCC Graphics Designer.
* Open the affected picture (.pdl); verify that the motor icon is anchored to the correct technological coordinates.
* Save the picture.
Download Complete OS to Server and Invalidate Client Cache:
* In SIMATIC Manager, right-click the OS project and select PLC > Download.
* Download the complete OS project to the active OS Server over the Terminal Bus.
* In WinCC Explorer on the OS Server, right-click Server Data and select Create.
* On each OS Client workstation, deactivate runtime or delete local temporary picture cache files (C:\Users\<User>\AppData\Local\Temp or local project copy).
* Download the updated Server Data package to the clients and restart runtime.

Verification

Initiate an AS/OS compile from ES 2 over the network; verify that driver generation completes with zero errors. On the OS Client workstation, open the modified process picture in WinCC Runtime. Verify that the motor block icon renders at its exact intended physical coordinate alongside the piping diagram, rather than jumping to (0,0) in the upper-left corner. Click the icon; verify that the APL faceplate opens cleanly.

Limitations and Operational Precautions

While the PCS 7 Standard Library V7.1 SP4 provides migration compatibility in PCS 7 V9.0 SP3, Siemens strongly recommends modernizing legacy loops to the Advanced Process Library (APL) during major upgrade cycles, as legacy standard library blocks will eventually be deprecated in future releases.

Engineer FAQ

Why did the picture look correct on the OS Server but broken on the OS Client?

OS Clients rely on Server Data packages and local screen caching. If the updated picture files are not deployed to the server or the client cache is stale, coordinates default to (0,0).

Can I mix CH_AI and Pcs7AnIn in the same AS controller?

Yes. A controller can run both legacy Standard Library drivers and APL drivers simultaneously, provided both library packages are installed on the Engineering Station.

Why does opening the multiproject from ES 2 cause errors?

If ES 2 lacks optional software packages (e.g., Standard Library V7.1 SP4, Drive ES, or S7 F Systems) installed on ES 1, cross-network compilation will fail.

What does 'Generate module drivers' do when it fails?

It checks the hardware configuration against the block library. If matching device XML templates are missing from the engineering disk, compilation aborts.