1. MP277 Family Overview
The SIMATIC MP277 is a Multi Panel generation released in the WinCC flexible era. It supports both touch-only and key-operated variants in 7.5" and 10.4" display sizes, all driven by the same 640×480 TFT pixel format. The configuration environment is WinCC flexible 2008 (SP2 or higher recommended for backtransfer reliability).
| Variant | Order Number Reference | Display | Touch | Keys | Configuration Tool | PROFINET |
|---|---|---|---|---|---|---|
| MP 277 8" Touch | 6AV6 643-0CB01-1AX1 | 7.5" TFT, 640×480 | Analog resistive | — | WinCC flexible 2008 SP2+ | Optional via IF module |
| MP 277 8" Key | 6AV6 643-0CB01-1AX0 family | 7.5" TFT, 640×480 | — | 26 system keys | WinCC flexible 2008 SP2+ | Optional via IF module |
| MP 277 10" Touch | 6AV6 643-0CD01-1AX1 | 10.4" TFT, 640×480 | Analog resistive | — | WinCC flexible 2008 SP2+ | Optional via IF module |
| MP 277 10" Key | 6AV6 643-0CD01-1AX0 family | 10.4" TFT, 640×480 | — | 34 system keys | WinCC flexible 2008 SP2+ | Optional via IF module |
2. Backtransfer (Upload) — The Critical Prerequisite
The MP277 only permits a project upload (called Backtransfer in WinCC flexible terminology) if the original download to the panel was performed with the "Enable backtransfer" option activated. There is no on-panel override and no recovery mechanism if the flag was not set; the project image is stripped of source data during a non-backtransfer download.
2.1 Download dialog sequence
- In WinCC flexible 2008 SP2, open the target project.
- Select Project → Transfer → Transfer Settings and configure the channel (MPI/PROFIBUS/Ethernet).
- Right-click the HMI station and choose Transfer → Transfer to target device.
- In the Transfer dialog, expand Options and tick "Enable backtransfer" (also labelled Overwrite enable for backtransfer in some builds).
- Confirm with Transfer. The panel stores the compressed project including compiled screens, scripts, recipes, and the source structure.
2.2 What is preserved in a backtransfer-enabled image
- Compiled screens (re-editable as WinCC flexible 2008 source)
- Tag database, alarms, and recipes
- VBS scripts and C scripts
- Scheduled tasks and area pointers
- User administration and password list
2.3 What is NOT preserved
- Runtime data: process values, current recipe records, alarm log entries, audit trail
- PLC-side configuration (the upload only recovers the HMI portion)
- Firmware of the panel itself
3. WinCC flexible 2008 Upload (Backtransfer) Procedure
3.1 PC-to-Panel connection
Three connection paths are supported by the MP277 for backtransfer:
| Path | Hardware Required | Typical Use |
|---|---|---|
| Serial RS-232 (MPI/PPI) | 6ES7 901-3CB30-0XA0 PC/PPI cable | Older installations, legacy PLCs |
| PROFIBUS DP | CP 5611 / CP 5613 / CP 5711 | Integrated PROFIBUS networks |
| Ethernet (PROFINET) | Standard TCP/IP, IF Ethernet module or onboard port (10/100) | Modern brownfield upgrades |
3.2 Initiating the upload
- On the panel, enter the Transfer menu (or set Transfer Mode from Control Panel → Transfer if autostart is disabled).
- The panel displays its IP / MPI address and waits for a transfer request.
- In WinCC flexible 2008 SP2, select Project → Transfer → Backtransfer from device.
- Choose the connection channel and start the transfer. The upload creates a new WinCC flexible project named
<DeviceName>_Backtransferin the configured project directory. - Validate the recovered project by opening it and confirming screen count, tag count, and alarm count match the original documentation.
4. Migrating WinCC flexible 2008 SP2 to TIA Portal WinCC
The TIA Portal WinCC migration tool converts a WinCC flexible 2008 SP2 project (including a backtransfer-recovered file) into a TIA Portal V13+ project. The migration preserves approximately 95–98 % of the project content; the remaining items require manual rework.
4.1 Prerequisites
| Item | Required Version |
|---|---|
| TIA Portal | V13 SP1 Update 4 or higher (V15.1 / V16 / V17 recommended for current Comfort Panel firmware) |
| WinCC flexible 2008 SP2 | SP2 with HF installed (for source compatibility) |
| License | WinCC Comfort / WinCC Advanced (TIA Portal) per target panel |
| Runtime license key | Transferred to the Comfort Panel via TIA Portal "Load" operation |
4.2 Migration workflow
- Open TIA Portal and select Project → Migrate project.
- Select the source
*.hmi/*.fwxWinCC flexible project file. - Choose a target device — initially keep the MP277 device to validate the conversion before swapping to a Comfort successor.
- Run the migration. TIA Portal produces a migration log (
.xml) listing warnings, errors, and unsupported elements. - Open the migrated project and review the log. Address each warning manually.
4.3 Common conversion warnings and remediation
| Warning | Cause | Remediation |
|---|---|---|
| Unsupported VBS function | Legacy HMIRuntime calls |
Map to TIA Portal equivalent; some properties renamed |
| Alarm class not migrated | Custom alarm classes | Recreate in TIA Portal alarm configuration |
| Driver-specific tag lost | Old SIMATIC panel drivers | Re-assign using current S7-1200/1500 driver |
| Recipe structure warning | Element name length or characters | Rename elements to comply with TIA naming rules |
| Graphics with absolute paths | Network share references | Embed graphics in TIA project |
5. Successor Panel Mapping (MP277 → Comfort)
The 8" and 10" MP277 variants map to the 9" and 12" Comfort Panel family. All successors offer higher resolution, wider color gamut, and modern PROFINET interfaces.
| MP277 Source | Direct Successor | Display Area Gain | Resolution | Touch / Key |
|---|---|---|---|---|
| MP 277 8" Touch | SIMATIC TP900 Comfort (6AV2 124-1JC01-0AX0) | ~32 % more display area | 800×480 WVGA, 16.2 M colors | Capacitive multi-touch |
| MP 277 8" Key | SIMATIC KP900 Comfort (6AV2 124-1JC01-0AX0 K variant) | ~32 % more display area | 800×480 WVGA | Mech. keys + touch |
| MP 277 10" Touch | SIMATIC TP1200 Comfort (6AV2 124-1MC01-0AX0) | ~22 % more display area | 1280×800 WXGA | Capacitive multi-touch |
| MP 277 10" Key | SIMATIC KP1200 Comfort (6AV2 124-1MC01-0AX0 K variant) | More area, WXGA | 1280×800 WXGA | Mech. keys + touch |
6. Cutout Dimensions and Mechanical Compatibility
The 8" Comfort panels are mechanically mounting-compatible with the MP277 8" family; the 12" Comfort panels exceed the 10" MP277 cutout. Verify dimensions before ordering:
| Panel | Front Bezel W×H (mm) | Cutout W×H (mm) |
|---|---|---|
| MP 277 8" Touch | 236 × 174 | 222 × 160 |
| MP 277 8" Key | 306 × 209 | 281 × 175 |
| MP 277 10" Touch | 335 × 245 | 310 × 220 |
| MP 277 10" Key | 417 × 288 | 382 × 252 |
| TP900 Comfort | 274 × 190 | 250 × 166 |
| KP900 Comfort | 362 × 230 | 338 × 206 |
| TP1200 Comfort | 331 × 226 | 310 × 205 |
| KP1200 Comfort | 435 × 290 | 414 × 268 |
7. Project Element Compatibility Matrix
| WinCC flexible Element | TIA Portal WinCC Status | Action Required |
|---|---|---|
| Tags (internal / external) | Migrated | Verify array limits; HMI tags now support 32-bit in TIA |
| Alarms (discrete, analog) | Migrated with class check | Reassign custom alarm classes |
| Recipes | Migrated, structure preserved | Re-validate element data types |
| VBScripts | Mostly migrated | Replace HMIRuntime references with SmartTags / HMI namespace |
| C-Scripts | NOT migrated (deprecated in TIA) | Rewrite as VBScript or use system functions |
| Schedules | Migrated | Recompile trigger tags |
| Logs (alarm, process, audit) | Migrated to TIA logging | Configure new database or CSV path |
| User administration | Migrated | Re-import users; SIMATIC Logon replaces local list |
| Sm@rtAccess / Sm@rtService | Migrated to Sm@rtServer | Enable Sm@rtServer in Comfort runtime |
| PROFIBUS DP connections | Migrated as PROFINET | Re-establish PLC connection via PROFINET |
8. Migration Procedure Step-by-Step (MP277 → TP/KP Comfort)
- Recover the source: Perform a backtransfer using WinCC flexible 2008 SP2 (see §3).
- Backup the recovered project to an offline repository with the original customer documentation (tag list, EPLAN drawings, cable schedule).
- Open TIA Portal with a WinCC Comfort license active.
- Migrate via Project → Migrate project → WinCC flexible project.
- Review the migration log in the TIA Portal "Info" pane and address warnings.
- Change the target device from MP277 to the corresponding Comfort Panel (e.g., MP 277 10" Touch → TP1200 Comfort).
- Adapt the screens to the new resolution (640×480 → 800×480 or 1280×800). Use Adapt to new resolution in the screen editor to reflow objects.
- Re-assign the PLC connection to PROFINET. Update the HMI device IP and PLC IP / rack / slot.
- Re-validate recipes, alarms, and scripts with a desk test using PLCSIM.
- Compile the TIA Portal project (Hardware → Compile, Software → Compile).
- Download to the Comfort Panel with Enable backtransfer again enabled.
- Functional test on the machine with the production PLC online.
9. Recipe, Script, and Alarm Migration — Deep Dive
9.1 Recipes
TIA Portal stores recipes in the same conceptual model but uses a flat element naming convention. Array limits in WinCC flexible were 100 elements per recipe; TIA Portal extends this to 1000 with the Comfort runtime.
9.2 Scripts
VBScript migrates cleanly except for the HMIRuntime.BaseScreenName and similar legacy properties. Replace with:
SmartTags("TagName") for tag access and HMI.ShowScreen("ScreenName") for screen navigation.
C-Scripts must be rewritten. TIA Portal supports VBScript and system functions only. For complex logic, consider extracting C logic to the PLC (S7-1200 / S7-1500) and calling it via function blocks.
9.3 Alarms
Alarm classes in WinCC flexible 2008 (Errors, Warnings, Information, System) map to TIA Portal alarm classes. Custom classes need to be recreated, and acknowledgment models are explicit in TIA Portal — the implicit "always acknowledged" behavior of some WinCC flexible setups is gone.
10. Communication Driver Equivalence
| WinCC flexible Driver | TIA Portal Driver | Notes |
|---|---|---|
| SIMATIC S7 300/400 (MPI / PROFIBUS) | S7 300/400 | Direct migration; verify MPI baud rate |
| SIMATIC S7 200 (PPI / MPI) | S7 200 (legacy driver) | Migrates; consider migrating PLC to S7-1200 |
| SIMATIC S7 1200 / S7 1500 | S7 1200 / S7 1500 | Native support, PROFINET recommended |
| OPC DA | OPC UA Client | OPC DA deprecated in TIA; map to OPC UA server on PLC |
| Modbus TCP / RTU (via OPC) | Modbus TCP / RTU native | Comfort Panels support Modbus natively |
11. Verification and Commissioning Checklist
| # | Check | Method | Pass Criterion |
|---|---|---|---|
| 1 | Project compiles | TIA Portal "Compile all" | 0 errors, warnings documented |
| 2 | Tag count vs original | Compare project stats | Match (or documented delta) |
| 3 | Alarm count vs original | Compare project stats | Match |
| 4 | Recipe round-trip | Write → reload → verify | Identical values |
| 5 | PLC live tags update | Toggle in PLCSIM, observe HMI | < 1 s update |
| 6 | Sm@rtServer connectivity | Browser / SmartClient | Session established |
| 7 | User login / role enforcement | Login as operator / admin | Correct visibility per role |
| 8 | Audit trail recording | Trigger operator action | Entry in audit log |
| 9 | Backtransfer from Comfort | Upload, compare to source | Identical screen count |
| 10 | Power-cycle recovery | Hard reset, observe boot | Project loads, connections restore |
12. Troubleshooting Matrix
| Symptom | Likely Cause | Resolution |
|---|---|---|
| Upload (backtransfer) returns "No project on device" | Original download performed without backtransfer flag | Recover project from engineering backup; document for future |
| Upload succeeds but recovered project missing scripts | Compacted runtime mode used at download | Re-download with backtransfer + full source; never use compact mode for serviceable panels |
| Cannot connect for upload | Wrong PG/PC interface or firewall on Ethernet | Set SIMATIC PG/PC interface to the correct adapter; disable Windows firewall for engineering VLAN |
| Panel stuck in transfer mode | Autostart enabled after failed transfer | Open Control Panel on device, switch back to manual start |
| Migrated project shows red dots on tags | PLC connection missing or wrong address | Configure HMI connection in TIA Portal Devices & Networks |
| Recipe data corrupted after migration | Data type change (e.g., INT → DINT) | Re-save recipes on first machine run with new runtime |
| Touch calibration drift on new Comfort | Capacitive vs resistive difference | Recalibrate via Control Panel → Touch |
| Display flicker or brightness issues | Inverter cable not seated after swap | Reseat LVDS cable; verify panel firmware ≥ V14.0.1.0 |
| Sm@rtServer HTTPS warning in browser | Self-signed certificate | Install plant CA certificate on client browser |
13. Field-Engineer Best Practices
- Always perform the first MP277 download with Enable backtransfer; you cannot enable it after the fact.
- Store the engineering project on a versioned repository (Git/SVN) with a tag per machine serial number.
- When upgrading to a Comfort Panel, perform the migration in a sandbox TIA Portal project first, then promote.
- Document tag renaming and array index shifts in the migration log; the PLC tag list will not change but HMI references can be updated independently.
- Test on a bench rig with PLCSIM before a plant shutdown.
- Keep the original WinCC flexible project and the migrated TIA Portal project side-by-side during the warranty period for quick rollback.
14. Related Siemens Tools and References
- Siemens Industry Online Support — official KB and manual portal.
- SIMATIC HMI Manual Collection — TP/KP Comfort Panel manuals.
- WinCC flexible → TIA Portal migration guide — official migration documentation.
- TIA Portal Help (WinCC) — integrated help inside TIA Portal.
- SIMATIC Comfort Panel product page — TP900 / KP900 / TP1200 / KP1200 family.
Can I upload a project from an MP277 if backtransfer was never enabled?
No. The panel stores a stripped runtime image when "Enable backtransfer" is not ticked during download. Recovery requires the original WinCC flexible engineering project from backup. This is the single most common cause of lost HMI source code on Multi Panel installations.
Which WinCC flexible version is required to backtransfer an MP277?
WinCC flexible 2008 SP2 is the minimum recommended version, with all hotfixes installed. Earlier SPs and the original WinCC flexible 2007 may connect but produce incomplete recovered projects or fail to deserialize certain script objects.
Is the TP900 Comfort a drop-in replacement for the MP277 8" Touch?
Not mechanically. The TP900 Comfort has a 250 × 166 mm cutout versus the MP277 8" Touch at 222 × 160 mm. It is mounting-compatible at the door level, but the cutout must be enlarged by ~28 mm horizontally and ~6 mm vertically, or an adapter plate used. The 9" WVGA display is ~32 % larger in area than the 7.5" VGA MP277.
What happens to C-Scripts during TIA Portal migration?
C-Scripts are not migrated. They must be rewritten in VBScript or moved to the PLC as structured logic (SCL / STL / LAD). TIA Portal runtime on Comfort Panels supports VBScript and system functions only; there is no C-Script interpreter.
Does the migrated project retain OPC DA connectivity?
OPC DA is deprecated in TIA Portal. The recommended path is OPC UA — enable the OPC UA server on the S7-1500 (or use a separate OPC UA gateway for legacy controllers) and configure the Comfort Panel as an OPC UA client. The migration tool logs a warning and removes the OPC DA channel.