Backing Up a Siemens LOGO! 230RC (0BA5) Program: Step-by-Step Field Procedure

The Siemens LOGO! 230RC with order number 6ED1052-1FB00-0BA5 belongs to the 0BA5 hardware generation and is one of the most deployed micro-PLCs in light commercial and residential automation. Despite the device's age, the upload procedure still depends on a small set of specific tools: LOGO!Soft Comfort V6 or V7, the 6ED1057-1AA01-0BA0 USB PC cable, and a manual transfer-mode keystroke sequence on the 0BA5 base module. This article walks through the complete backup procedure, identifies the successor (0BA6) part number, and provides a troubleshooting matrix for the most common field failures.

1. Hardware Identification: Confirming the 0BA5 Variant

Before launching any software, confirm the exact MLFB printed on the side label of the LOGO! base module. The Siemens naming convention for the 230RC is:

The 230RC designation decodes as 230 V AC supply, Relay outputs, C-variant. The "R" suffix indicates electromechanical relay outputs (Q1–Q4 rated 8 A resistive / 2 A inductive at 230 V AC). The "C" distinguishes the AC-powered variant from the 24 V DC versions (12/24RC, 24RCo, etc.).

Locate the order number on the right-hand side label of the device, in the format 6ED1052-1FB00-0BAx. The trailing -0BAx is the critical field: 0BA5 must be selected in LOGO!Soft Comfort as "0BA5 Standard" before uploading, otherwise the software rejects the connection.

2. Prerequisites: Software, Cable, and Host PC

Three components are required to back up a 0BA5 program:

1. LOGO!Soft Comfort V7 (or V6.x) installed on a Windows PC with administrator rights.
2. LOGO! PC USB cable, MLFB 6ED1057-1AA01-0BA0. This cable integrates a USB-to-serial converter and exposes a virtual COM port to LOGO!Soft Comfort. The older 6ED1057-1CA00-0BA0 serial cable is a fallback for pre-USB hosts but requires a physical COM port.
3. The 0BA5 base module powered and wired with at least L1 / N mains supply (115–230 V AC, 50/60 Hz). The CPU does not need to be in RUN; the upload works in STOP or RUN.

3. Installing LOGO!Soft Comfort V7

LOGO!Soft Comfort V7 supports all generations from 0BA5 through 0BA7 on a single install. V8.x added 0BA8 Ethernet support but retained backward compatibility for older targets.

1. Insert the LOGO!Soft Comfort V7 DVD or run the downloaded installer as Administrator. The default install path is C:\Program Files\Siemens\LOGOComfort_V7\.
2. Accept the license agreement and choose Typical installation. This installs the FBD/LAD editor, the simulator, the online help, and the USB cable driver package.
3. If the installer does not auto-install the USB cable driver (6ED1057-1AA01-0BA0), the driver package is located at C:\Program Files\Siemens\LOGOComfort_V7\Drivers\. Point Windows Device Manager to this folder when prompted.
4. Reboot the PC. After reboot, confirm the cable is detected by plugging it in and checking Device Manager → Ports (COM & LPT). The cable should appear as USB Serial Port (COMx) where x is the assigned COM number (typically COM3–COM6).

4. Wiring the 6ED1057-1AA01-0BA0 USB Cable

The 6ED1057-1AA01-0BA0 cable has two ends:

• USB-A: connects to the host PC.
• RJ12 (6P6C) modular plug: mates with the recessed serial socket behind the small cover on the front of the LOGO! base module.

To connect:

1. Power the LOGO! 230RC at L1/N. The unit does not need to be in RUN.
2. Flip open the small plastic cover on the front face of the LOGO! (between the display and the terminal block). The serial socket sits underneath.
3. Insert the RJ12 plug of the 6ED1057-1AA01-0BA0 cable. It is keyed; do not force it. A positive click indicates a proper mate.
4. Plug the USB-A end into the PC. The PC should emit the standard USB-enumeration chime, and Device Manager should show a new COM port.

5. Putting the 0BA5 into PC <-> LOGO! Transfer Mode

Unlike 0BA7 and 0BA8, the 0BA5 does not auto-detect the PC cable. The user must manually toggle the device into transfer mode. The procedure depends on whether the unit has a display (LOGO! 230RC with display, MLFB suffix differs) or is a display-less variant:

5.1 For 0BA5 units with integrated display (LOGO! 230RC, 6ED1052-1FB08-0BA5)

1. On the LOGO! front panel, press ESC to enter the main menu.
2. Navigate with the ↑ / ↓ keys to Start.
3. Press OK.
4. Select PC <-> LOGO! using the cursor keys.
5. Press OK. The display now shows PC <-> LOGO! with a status icon. The unit is in transfer mode.

5.2 For 0BA5 units without integrated display (the source MLFB 6ED1052-1FB00-0BA5, the "R" model)

The display-less variant has no on-screen menu. Transfer must be initiated from the host PC in LOGO!Soft Comfort:

1. Open LOGO!Soft Comfort V7.
2. Click Tools → Transfer → PC → LOGO! (or simply press the Upload button on the toolbar — the blue arrow pointing toward the PC).
3. LOGO!Soft Comfort will issue a transfer command. The 0BA5 will respond by exiting RUN and entering STOP with the transfer active. The on-module LEDs (RUN green, STOP red) will indicate the state change.

6. Uploading the Program: Step-by-Step Procedure

Once the cable is connected and the COM port is visible:

1. Launch LOGO!Soft Comfort V7.
2. Click File → New (or press Ctrl+N). A blank FBD or LAD project opens.
3. In the device-selection dialog, choose LOGO! 0BA5 Standard. This is critical — selecting "0BA6" or "0BA7" will prevent the upload from completing because the firmware versions are incompatible.
4. From the menu, click LOGO! → PC (Upload). The keyboard shortcut is Ctrl+U in V7. The on-screen icon is a blue arrow pointing left (from LOGO! to PC).
5. Select the COM port assigned to the 6ED1057-1AA01-0BA0 cable (e.g., COM3). If unsure, check Device Manager.
6. Click Test to verify the cable connection. A green status indicator confirms communication. A red indicator means the LOGO! is not in transfer mode or the COM port is wrong.
7. Click Upload. The progress bar shows the transfer. A typical 0BA5 program (40–60 function blocks) uploads in 5–15 seconds.
8. When the upload completes, the FBD/LAD program appears in the editor window. Save the project immediately as a .lsc file (LOGO!Soft Comfort project) and a .lma export (LOGO! program module archive) for redundancy.

7. Saving the Backup in Multiple Formats

A single .lsc file is the master copy, but storing additional formats protects against version-mismatch issues if the backup must be reloaded onto a different generation:

To export the .lma program-module image: File → Export → LOGO! Program Module File (.lma). This format is required if you intend to clone the program onto a spare 0BA5 (or compatible 0BA6) without going through the upload-over-cable path.

8. Verifying the Backup

A backup that uploads but does not match the running process is a liability. Verify integrity with these checks:

1. Function-block count parity. Open the original LOGO! menu (on a display-equipped unit): ESC → Program → Edit. Note the function-block count. Cross-check the count in the uploaded .lsc by selecting all blocks in the editor (Ctrl+A) and reading the status bar.
2. Online compare. In LOGO!Soft Comfort, click LOGO! → Compare with Online. Any difference highlights in red.
3. Simulator run. Open the integrated simulator (Tools → Simulator) and step through the logic with simulated inputs. The simulator runs the same compiled code that the physical LOGO! runs, so behavior must match.
4. Cyclic reload test. If a spare 0BA5 (or 0BA6) is available, download the .lsc to it via LOGO! → PC (Download) and let it run for at least one full operating cycle of the controlled process. The original may be left in place as a hot spare.

9. Troubleshooting Matrix: Common Upload Failures

10. Migrating from 0BA5 to 0BA6 (Direct Successor)

The 6ED1052-1FB00-0BA6 is the direct successor to the 0BA5. It shares the same footprint, terminal layout, and I/O assignment, making it a drop-in replacement. However, two differences must be accounted for:

1. Newer function-block set. The 0BA6 firmware introduces additional blocks (e.g., astronomical timer, additional analog math). Programs uploaded from a 0BA5 to 0BA6 will run, but a 0BA6 program cannot always be downgraded to a 0BA5.
2. LOGO!Soft Comfort device selection. When targeting a 0BA6, select LOGO! 0BA6 Standard in the project properties before downloading. Selecting 0BA5 by mistake will succeed in the upload but the program will use only the smaller 0BA5 instruction subset.

To perform the hardware swap after backing up the 0BA5 program:

1. Power down the system. Label every wire on the 0BA5.
2. Remove the 0BA5 and install the 0BA6. The terminal screws and pin-out are identical.
3. Re-apply power. The 0BA6 will boot in STOP with all outputs off.
4. Open the backup .lsc file in LOGO!Soft Comfort V7, change the target device to 0BA6 Standard, and download via the 6ED1057-1AA01-0BA0 cable.
5. Toggle the 0BA6 to RUN. Verify I/O wiring by forcing inputs from LOGO!Soft Comfort (Tools → Online → Force Inputs).

11. Compatibility Matrix: Software and Firmware

For a 0BA5 target, LOGO!Soft Comfort V7 is the recommended version: it supports the upload, it recognizes the 6ED1057-1AA01-0BA0 USB cable out of the box, and it preserves the option to upgrade the target hardware to 0BA6 or 0BA7 without reformatting the program.

12. Frequently Asked Questions