TP270 PSB to PDB Conversion: Limits and Migration Path

Field engineers frequently attempt to open a Siemens TP 270 backup file (*.psb) in ProTool as an editable configuration (*.pdb). The two formats are not interchangeable: a *.psb file is a compressed device image captured by ProSave, while a *.pdb is the editable offline project created in ProTool or ProTool/Pro. This article explains why the conversion is impossible, documents the backup/restore workflow on the TP 270, and lays out the practical migration path to TP 277, WinCC Flexible, and TIA Portal.

1. Problem Statement

You captured a panel image from a TP 270 with ProSave (file extension *.psb). You want to modify screens, tags, or alarms, so you attempt to open the file in ProTool to obtain the editable *.pdb source. ProTool reports that it cannot load the file, or the file is not recognized at all.

2. File Format Comparison: *.psb vs *.pdb

3. Why Direct Conversion Is Not Possible

The *.psb container wraps the compiled output that the TP 270 executes: internal symbolic tag names are hashed, screen graphics are converted to internal primitives, and tag addresses are stored as raw numeric pointers into PLC areas (DB, M, I, Q). The *.pdb source contains the human-readable tag names, screen objects, alarm texts, and area pointers that the compiler uses to build the runtime image.

The transformation between the two formats is strictly one-way:

*.pdb (source)  ->  ProTool compiler  ->  Runtime image (*.psb / *.csp / *.brf)
                     ^
                     |  reverse engineering not supported by Siemens
                     |
                 *.psb (cannot be decoded back to *.pdb)

Siemens does not ship a decompiler for ProTool runtime images, and the *.psb container is documented as an image-only format in the Siemens Industry Online Support knowledge base. Any third-party tool that claims to extract a project from a *.psb file is either incomplete (recovers a subset of objects), unstable across firmware revisions, or in violation of the licensing terms.

4. ProSave Backup Workflow on TP 270

4.1 Prerequisites

• ProSave version compatible with the TP 270 firmware revision (typically ProSave V6.x or V7.x bundled with ProTool/Pro V6.x, refer to the Siemens TP 270 entry page for the exact pairing matrix).
• Connection cable: MPI, PROFIBUS, USB-to-Serial (PC/PPI), or Ethernet (TP 270 10" has onboard Ethernet; the 6" model does not).
• MPI/PROFIBUS address of the panel (default 1, 2, or as configured in the Control Panel -> Transfer menu).
• TP 270 in Transfer mode (Control Panel -> Transfer -> Start, or set the Coord bit in the PLC area pointer).
• Local administrator rights on the engineering PC for ProSave driver installation.

4.2 Backup Procedure

1. Launch ProSave on the engineering PC.
2. Select Device type -> TP 270 (the catalog list shows both 6" and 10" variants — pick the one matching the panel MLFB).
3. Select the connection channel: S7ONLINE for MPI/PROFIBUS or TCP/IP for Ethernet.
4. Set the panel address (e.g., MPI = 1).
5. Click Backup. The dialog offers Active backup (current runtime state including recipes, logs, user administration) and Passive backup (default image without volatile data). Choose Active if you need historical data; choose Passive for a fast image-only clone.
6. Specify the destination path and filename. ProSave creates a *.psb file together with a *.pdf transfer protocol and optionally a *.log file.

4.3 Restore Procedure

1. Connect to the same or an identical panel (TP 270 with identical MLFB and firmware version).
2. Place the panel into Transfer mode via Control Panel or the Coord area pointer bit.
3. In ProSave, select Restore and choose the *.psb file.
4. Confirm the panel prompt — restoring overwrites the runtime image and may trigger an automatic reboot. Panel prompts are language-dependent (German, English, French, Italian, Spanish, Chinese are common).
5. Verify the restore by reading back the version info: Control Panel -> Version.

5. ProTool Configuration Workflow (Editable *.pdb)

If the source *.pdb file exists, you can modify it directly:

1. Open ProTool/Pro V6.0 SP3 (or later) or ProTool V6.0.
2. File -> Open -> select *.pdb.
3. Edit screens, tags, alarms, area pointers, recipes.
4. Compile the project (Project -> Compile -> check the warning tab).
5. Transfer the new runtime back via ProSave -> Restore (image) or via ProTool -> Download -> Project (project only, preserves panel-internal data).

Note that compilation will fail if the panel firmware revision is older than what the project requires. The TP 270 supports Windows CE 3.0 with Image 6.0.1 as a typical toolchain combination; ProTool/Pro V6.0 SP3 generates Image 6.x-compatible runtimes.

5.1 Component-Level View of a *.pdb

• Screen library (*.gra / vector objects)
• Tag list with PLC area pointers (DBx.DBBy, Mx.y, Ix.y, Qx.y)
• Alarm messages with acknowledgment strategy
• Recipes (structure, storage location, sync target)
• User administration (passwords, authorization levels)
• Scripts (ProTool script or VB)
• Scheduling (cyclic, once, daily, weekly)

6. Recovery Strategies When Only a *.psb Exists

6.1 Locate the field report

• Check the engineering server's archive folder for the matching *.pdb.
• Check the commissioning record and as-built documentation; most plants archive the source project under the plant tag or area code (e.g., \archives\PlantA\Area51\TP270\_pdb\).
• Search the original integrator's backup tape, USB stick, or version control repository (SVN, Git LFS).
• Check for an exported ProTool backup CD or DVD that was part of the project handover.

6.2 Request the Source from the OEM/Integrator

The system integrator or machine builder is contractually obligated (in most EU and US jurisdictions) to provide the editable source for the lifetime of the installed base. Provide the panel MLFB, the firmware version shown in Control Panel -> Version, and the *.psb as evidence of the configuration. The MLFB and Image version together uniquely identify the runtime and constrain the source *.pdb's revision range.

6.3 Recover Screen Text via HMI Upload

Some HMI panels expose a partial upload through the Windows CE Remote Display tools. You can capture live screen contents using VNC or a remote ActiveX container and reproduce the layout manually. This is a last-resort reverse-engineering effort, not a sanctioned workflow, and is not recommended for production deployments.

6.4 Rebuild from PLC Source and Documentation

If PLC tags and area pointers are documented in the STEP 7 / TIA Portal project, the *.pdb can be reconstructed manually by creating a new ProTool project with the same tag database, area pointers, and screen layout from screenshots or paper drawings. This is labor-intensive but feasible for panels with fewer than 30 screens.

7. Migration Path: TP 270 -> TP 277 -> TIA Portal

The TP 270 was phased out of production. Current field strategy is to migrate to the TP 277 running WinCC Flexible 2008 SP5 or to TIA Portal WinCC targeting a Comfort Panel. The migration has three well-defined steps. Reference the Siemens migration guides for version-specific details.

7.1 Step 1 — Migrate *.pdb to *.hmi (WinCC Flexible)

1. Open WinCC Flexible 2008 SP5 (or later).
2. File -> Migrate Project -> select the ProTool/Pro *.pdb.
3. The migration wizard converts screens, tags, alarms, and recipes. Manual reconciliation is required for unsupported functions (e.g., ProTool-specific scripts not supported in WinCC Flexible).
4. Save as *.hmi or *.fwx.

7.2 Step 2 — Migrate *.hmi to TIA Portal (Optional)

1. In TIA Portal V16 or later, open the TIA Migration Tool.
2. Select the WinCC Flexible project.
3. Choose the target Comfort Panel (TP700, TP900, TP1200 Comfort).
4. Resolve the migration report — most TP 277 projects migrate cleanly to TP700/900/1200 Comfort with minimal manual rework.

7.3 Step 3 — Verify with HMI Tag Simulation

1. Use WinCC Flexible or TIA Portal runtime simulation to load the migrated project.
2. Connect to a S7-300/400/1200/1500 PLC simulation (PLCSIM or PLCSIM Advanced).
3. Confirm all tags, alarms, and area pointers resolve correctly before commissioning.
4. Test all recipes end-to-end, especially if the migration tool changed recipe element data types.
5. Validate scripts by triggering each ProTool script equivalent and checking the VBScript replacement for parity.

8. ProTool vs WinCC Flexible vs TIA Portal Feature Comparison

9. Connection Topologies for ProSave

ProSave can connect to a TP 270 over four transports. Choose based on the panel hardware variant and the available PLC network.

9.1 MPI/PROFIBUS

• Use a Siemens PC adapter (e.g., USB-MPI for engineering PCs) or CP5611/CP5613 A2 PCI cards for workstations.
• Set PG/PC interface in STEP 7 or in the Windows Control Panel -> SIMATIC S7 PROTOCOL SUITE.
• Baud rate: 187.5 kbit/s default MPI, up to 12 Mbit/s for PROFIBUS on the 10" variant.
• Bus termination must be installed at both physical ends; the panel does not terminate by default.

9.2 Ethernet

• TP 270 10" has an onboard 10/100 Mbit/s RJ45 port. The 6" model does not.
• Set IP address in Control Panel -> Network -> TCP/IP, e.g., 192.168.0.10, mask 255.255.255.0.
• ProSave connection type: Ethernet (TCP/IP), port 102 (ISO-on-TCP).
• Confirm the engineering PC is in the same subnet or routed correctly. Disable Windows Firewall rules blocking port 102 during the transfer window.

9.3 USB

• TP 270 supports USB host for keyboard/mouse/USB stick but not USB-PPI for ProSave transfer.
• Use a serial PC/PPI cable (6ES7 901-3CB30-0XA0) into the panel's RS-232 sub-D port, if available, for legacy deployments.

9.4 PROFINET

• Not supported natively on TP 270. Migration to TP 277 Comfort or TP 700 Comfort is required.

10. Troubleshooting Matrix

11. Field-Proven Caveats

• Same MLFB only. A *.psb from a TP 270 6" cannot be restored to a TP 270 10"; the panel OS image and cutout dimensions differ.
• Firmware pinning. ProSave V6.0 SP3 cannot back up a TP 270 running Image 7.x. Match ProSave version to panel firmware revision exactly.
• Licensed functions. If the original project used a licensed ProTool option (e.g., OPC server, multi-protocol), the license key on the panel is restored with the *.psb but is not part of the *.pdb. The license is bound to the panel hardware, not the source file.
• Recipes and logs. Recipe data is held on the panel's CompactFlash or internal flash. If the flash is failing, both *.psb backup and active restore will be inconsistent. Verify flash health with the panel's diagnostic page (Control Panel -> System -> Memory).
• PLC tag numbering. After restoring, area pointers must still point to the correct DB offsets in the PLC. A project migration that changes tag structure requires a PLC-side recompile or DB remapping.
• Date/time drift. Panels without battery backup lose date/time on power cycle. Recipes that use date stamping will need their clocks re-set manually or via PLC time synchronization.
• Multi-protocol collisions. Some TP 270 installations used a parallel MPI and PROFIBUS connection (MPI to S7-400, PROFIBUS to S7-300). Verify both legs are correctly terminated before attempting a ProSave connection over either.

12. Preventive Measures for Future Projects

1. Always archive the *.pdb source in a version-controlled repository (SVN, Git LFS, or document management system) at every project release and at every change request.
2. Add a "Backup Bundle" file convention: <ProjectName>_<MLFB>_<Date>_v<Rev>.zip containing *.pdb, *.psb, PLC project backup, wiring diagram, and tag list.
3. Document the ProTool version, Image version, and firmware revision used for each release in a project README.
4. Schedule a migration audit every 5 years — the TP 270 was discontinued in 2008 and spare availability is now limited. Most European automation vendors have migrated to TP700/TP900/TP1200 Comfort panels by 2024.
5. Apply the principle of least privilege for password storage: keep passwords out of *.psb backups when possible by configuring the panel for re-prompt on restore.
6. For plants with regulatory audit requirements (FDA 21 CFR Part 11, EU GMP Annex 11), maintain a signed checksum of each archived *.pdb to demonstrate integrity.

13. Commissioning Checklist After Restore

1. Verify panel MLFB and Image version match the project (Control Panel -> Version).
2. Verify PLC connection: Test the Coord bit, area pointer read/write, and a sample tag poll.
3. Verify recipes: Trigger a write-to-panel, power cycle, and read-back to confirm persistence.
4. Verify alarms: Trigger an acknowledged alarm and a non-acknowledged alarm to confirm logging.
5. Verify user administration: Log in as each role, confirm permission level matches project specification.
6. Verify trend/log persistence: Confirm trend data is retained across panel reboot.
7. Verify script execution: Trigger each ProTool script and confirm expected output state on the PLC.
8. Verify network: Confirm the panel responds to a ping on its configured IP and accepts ProSave connections.

14. Common Engineering Errors When Migrating Off TP 270

• Tag length truncation: WinCC Flexible enforces a 32-character tag name limit; longer ProTool tag names are truncated and must be manually renamed.
• Area pointer byte swap: Area pointer offsets between ProTool and WinCC Flexible are identical, but pointer syntax changes — verify all DB offsets are re-entered correctly during migration.
• Font mapping: ProTool uses Siemens-Sans-Bold as default; WinCC Flexible uses Comfort fonts. Some glyphs (e.g., box-drawing characters) do not map cleanly.
• Color palette: ProTool uses 256-color palette; WinCC Flexible Comfort panels are 16M-color. Indexed colors convert to RGB but lose semantic grouping.
• Event handling: ProTool event-driven scripts (e.g., on tag change) map to WinCC Flexible scheduled tasks or VBScript event handlers; some edge-case events are dropped during migration.