TP177B PN/DP Backup and WinCC Flexible OS Update with S7-226

Overview

The Siemens TP177B PN/DP (6" STN, PN/DP variant, catalog 6AV6 642-0BA01-1AX1 family) is one of the most deployed compact panels in the S7-200 ecosystem. When the panel is paired with an S7-226 CPU (6ES7 216-2BD23-0XB0), three field issues surface repeatedly: backup transfers that fail over PPI and Ethernet, runtime projects that do not read/write the PLC, and OS/firmware version mismatches during a recompile in WinCC Flexible 2008 (and later 2008 SP2/SP3). This reference consolidates the engineering response to all three, including port topology, cable selection, ProSave procedures, license handling, and the "Enable Upload" (Reverse Upload) option that determines whether a panel can ever be restored to editable source.

System Topology and Port Identification

Before any backup, transfer, or runtime test, identify the physical port on each device. Confusion between RS-232 and RS-422/RS-485 pinouts is the single largest source of "communication error" reports on this combination.

Problem 1: Backup Transfer Fails Over PPI and Ethernet

Symptoms

• WinCC Flexible "Backup/Restore" wizard reports "Communication error" or "Device not responding".
• Ping to the TP177B LAN IP succeeds, but the backup still fails.
• Direct serial attempt on the S7-226 returns the same error.

Root Causes (ranked by frequency)

1. Transfer mode not enabled on the panel. TP177B ships with automatic transfer disabled. The user must call up the Control Panel on the panel and enable Transfer and, for Ethernet, the Remote Control / Channel for LAN.
2. Transfer channel misconfigured. The active channel for backup must match the physical medium (MPI/DP for serial, Ethernet for LAN). If the project was compiled for MPI and the panel is connected via Ethernet (or vice versa), the panel will reject the transfer handshake.
3. Password protection on the panel. If the loader is password-protected, WinCC Flexible will hang at handshake until the password is supplied in the transfer dialog.
4. Firewall or routing issue on the PC. Backup uses TCP port 102 (S7) plus 5001/5002 for some panel services. Even with a successful ping, a Windows firewall or VPN route can block these higher-layer ports.
5. Cable or converter mismatch. Connecting the PC RS-232 port to the TP177B IF 1B port with a generic DB-9 null-modem or with the RS-232/PPI cable (which is keyed for the S7-200) is the most common serial-side fault.

Solution: Enable and Verify Transfer

1. On the TP177B, press the Control Panel button (hold during boot if hidden).
2. Open Transfer → enable Serial (MPI/DP) and/or Ethernet as required.
3. Set Remote Control = Enable if the engineering station is to trigger the transfer without physical keypress on the panel.
4. On the PC, open a command prompt and confirm ping <panel_IP> returns under 5 ms with 0% loss.
5. In WinCC Flexible, open Project → Transfer → Backup, choose the active channel, enter the panel IP, and start the backup. Supply the panel password if prompted.

Problem 2: WinCC Flexible PC Runtime Does Not Read/Write the S7-226

Symptoms

• PC Runtime starts in simulation; tags remain gray or show "--".
• No connection error is raised, but value changes in STEP 7-Micro/WIN are not reflected in the Runtime.

Root Cause

The default PC Runtime connection parameter set in WinCC Flexible is a serial PPI link at 9 600 bit/s on COM1. The S7-226 Port 0 must be configured identically:

• Address: panel-side connection = 1, PLC = 2 (or as set in the project).
• Baud: 9 600 or 19 200 bit/s.
• Protocol: PPI or PPI Master in the S7-200 system block.

Solution

1. Connect the PC COM1 to S7-226 Port 0 using the RS-232/PPI cable (6ES7 901-3CB30-0XA0). The cable has a DIP switch for PPI/MPI/Freeport and baud rate; set to PPI/9 600.
2. In STEP 7-Micro/WIN, open System Block → Port 0 and assign address 2, PPI slave, 9 600 bit/s.
3. In WinCC Flexible, open Connections, set the active connection to SIMATIC S7 200, COM1, PPI, address 2.
4. Download the WinCC Flexible project to the PC Runtime and start it. The status icon in the Runtime should turn green within 3-5 seconds.

Problem 3: WinCC Flexible / Panel OS Version Mismatch

Symptoms

• Transfer is rejected with the message "Image version on the device is not compatible with the current project."
• OS update prompt appears during download.

Root Cause

WinCC Flexible 2008, 2008 SP1, 2008 SP2, and 2008 SP3 each contain different panel OS images. If the project was last compiled in SP3 and the panel still runs an SP1 image, the project is forward-compatible only if SP3 is allowed to update the image. If the project is older than the panel image, the transfer will fail.

Solution: Update the Panel OS

1. Open Start → SIMATIC → WinCC Flexible → ProSave (or invoke ProSave from inside WinCC Flexible: Project → Transfer → OS Update).
2. Select the device type (TP177B PN/DP) and the connection (Ethernet, MPI, or USB depending on cable).
3. Set the target image path. ProSave uses the images bundled in %ProgramFiles%\Siemens\Automation\WinCC Flexible\Images by default; do not point at a custom folder unless verified.
4. Click Update OS. The panel reboots into update mode, the image is flashed (typically 60-180 s), and the panel restarts into the loader.
5. After the OS update completes, re-run the project transfer.

Licensing on the TP177B PN/DP

The TP177B PN/DP does not require a runtime license for the standard HMI application. WinCC Flexible licenses are tied to the engineering PC and, optionally, to add-on services activated on the panel:

Because licenses are stored in a non-volatile region that the OS update does not erase, there is normally no need to extract and re-install them. If a license is reported missing after a major version jump (e.g., 2005 SP1 image replaced with 2008 SP3 image), the corrective action is to use Automation License Manager → Transfer License to push the panel license back from the engineering PC. The TP177B does not implement a user-accessible license key file; do not attempt to extract one manually.

Backup vs. Upload: A Critical Distinction

A Backup in WinCC Flexible/ProSave copies the compiled runtime image from the panel to disk. This file:

• Is binary, not editable in WinCC Flexible.
• Can only be restored to a panel of the same type and matching OS version.
• Contains tag names, screens, recipes, and alarms in compiled form but not the editable source.

An Upload (Reverse Upload / "Habilitar descarga retroactiva") recovers the editable source project from the panel. This is only possible if the option was checked at the original download time:

1. Open the WinCC Flexible project that was downloaded to the panel.
2. Go to Project → Transfer → Transfer Settings and confirm Enable Upload is checked.
3. Re-compile and re-transfer the project. The compiled image will then contain the source in a compressed annex.

If the original download did not enable upload, there is no supported method to recover the editable source. Only a fresh backup file can be restored. This is a one-way decision: enabling upload adds roughly 15-30 % to the project footprint on the panel, which is why most production deployments leave it off.

Recommended Workflow for a Fresh TP177B Project with an S7-226

1. Plan the topology: PC ↔ S7-226 via RS-232/PPI for development; PC ↔ TP177B via Ethernet for transfer and runtime.
2. Build the WinCC Flexible project: declare all tags with S7-200 area pointers (e.g., VW100, MB0, I0.0), keep cycle times at 1 s or longer for non-critical displays.
3. Validate on PC Runtime: use the RS-232/PPI link to the S7-226 first; confirm all read/write tags update in the Runtime.
4. OS-check the panel: from ProSave, read the current image version; compare to the WinCC Flexible build version.
5. Enable Transfer and Remote Control on the panel Control Panel.
6. Transfer the project to the TP177B over Ethernet; tick Enable Upload if the project is a development build.
7. Perform a backup immediately after a successful first transfer; archive the .psb/.bnk file with the project source.
8. Document license state if Sm@rtService or OPC is in use.

Troubleshooting Matrix

Field-Proven Caveats

• WinCC Flexible 2008 SP2 is the most widely deployed version for the TP177B PN/DP and is the lowest version that supports all firmware revisions of that panel family. Earlier 2005 SP1 images are common in legacy sites and will refuse 2008 SP3 projects without an OS update.
• For long Ethernet trunks, the TP177B LAN port auto-negotiates 10/100. A managed switch with port security can block the S7 protocol; disable MAC filtering during commissioning.
• The TP177B PN/DP variant does not support PROFINET device role on the LAN port; the PN suffix refers to Ethernet-based S7 communication, not PROFINET IO controller. Do not attempt to attach a PROFINET IO device to this panel.
• If the panel is password-protected and the password is lost, recovery requires a factory reset through ProSave, which erases the runtime image. This is the only method to clear an unknown panel password; budget a fresh transfer into the recovery procedure.
• Always keep a current .psb backup on the engineering PC and a current .hmi project source in version control (SVN, Git, TIA Portal Team Center gateway). The compiled backup is not a substitute for the source.