Overview: What the 6ED1052-1FB00-0BA6 Ships With
Ordering the Siemens LOGO! 6ED1052-1FB00-0BA6 (also written 0BA6, where the suffix 0BA6 denotes the LOGO! 8 hardware generation pre-0BA7) and powering it up reveals a remarkably complete logic relay out of the box. The base unit, an SD card slot for an optional LOGO! memory card, an Ethernet RJ45 socket, the integrated display (on the "R" logo version) or LED panel (on the "E" pure version), and the screw terminals for power and I/O are all in place. The three things a first-time user has to decide on before the first program transfer are:
- Which programming cable to use (USB, RS232, or built-in Ethernet on 0BA7).
- Whether a LOGO! memory card is required for the application.
- Whether the 80-hour internal super-cap backup is sufficient, or whether a LOGO! battery card is required.
The short answer, derived from the field experience of the Siemens support community and the LOGO! 0BA6 system manual, is: the cable you already own, the memory card is optional, and the battery card is only needed if retentive data or RTC retention beyond 80 hours matters. The rest of this reference expands each of those three points with specifications, behavior, and commissioning procedure.
Decoding the Catalog Number 6ED1052-1FB00-0BA6
Siemens' MLFB (Maschinenlesbare Fabrikate-Bezeichnung / machine-readable product designation) breaks the part number into functional groups. The 6ED1052 series identifies the LOGO! 8 logic module family.
| MLFB segment | Meaning |
|---|---|
| 6ED1052 | LOGO! 8 base module (logic relay with display/keypad) |
| 1FB | Family / variant code: pure variant with display (LOGO! 8.1 / 0BA6 generation) |
| 00 | Standard ordering form (no factory special firmware) |
| 0BA6 | Hardware generation; superseded by 0BA7 (adds cloud/web server + minor perf improvements) |
For the latest generation with native Ethernet programming, the equivalent order number is 6ED1052-1FB00-0BA7. Both 0BA6 and 0BA7 share the same physical footprint, I/O count, expansion bus, and accessory footprint (memory card, battery card, programming cable, soft Comfort project files). The Siemens LOGO! product selector is at siemens.com/logo and the entry page for the 0BA6 module is at Siemens Industry Online Support - 6ED1052-1FB00-0BA6.
Programming Cable: USB, RS232, or Ethernet?
Three physical options exist for getting a program from a PC into a LOGO! 0BA6. The selection is dictated by which interface you have on the host computer and which interface you are willing to fit to the LOGO! side.
| Cable | PC end | LOGO! end | Notes |
|---|---|---|---|
| LOGO! USB programming cable (Siemens article documented in support entry 27609308) | USB-A | 3-pin service port on the front of the LOGO! (the small triangular socket) | Preferred for new installations. No driver beyond the standard Windows HID/serial mapping is required for current Soft Comfort builds. |
| LOGO! RS232 (PC) programming cable | DB-9 male RS232 | Same 3-pin service port | Legacy option. Use only if you already own the cable. Many USB-to-serial converters enumerate as COM ports but fail the LOGO! boot handshake due to charge-pump timing; the genuine Siemens cable remains the safe choice. |
| Standard RJ45 Ethernet patch cable (0BA6 = LAN, 0BA7 = LAN) | RJ45 10/100 | RJ45 LAN port on the LOGO! 0BA6 / 0BA7 | Supported on LOGO! 0BA6 and later. 0BA7 also exposes a Web server on the same port. |
The official Siemens support page documenting the USB programming cable (the cable many LOGO! integrators first reach for) is Siemens support entry 27609308. The cable is the only practical choice on a modern laptop without a real DB-9 RS232 port; on industrial PCs and on any system with a native COM port, the older RS232 cable still works, but the RS232 cable is increasingly hard to source. Where the LOGO! sits on a switch with a reachable RJ45, a plain Cat5 patch cable and the on-board Ethernet of the LOGO! 0BA6/0BA7 is the lowest-friction option and is the recommended path on new projects.
Cable wiring at a glance
The LOGO! 3-pin service port is the same physical connector as the older LOGO! 0BA0 - 0BA5 service ports. Pinout:
- Pin 1: data (TTL-level, not RS232 levels - the genuine cable handles the conversion)
- Pin 2: ground
- Pin 3: +5 V supply from LOGO! to cable electronics
Do not feed an RS232 line-level signal onto this port without the Siemens adapter in line. The MCU side is 3.3 V TTL.
LOGO! Soft Comfort: Required PC Software
For any non-trivial program the on-device cursor-key editor is impractical. The PC-based tool is LOGO! Soft Comfort, available as a free download from Siemens with the following practical minimums:
| Soft Comfort version | LOGO! hardware supported | Notes |
|---|---|---|
| V6.0 - V6.1 | 0BA5, 0BA6 | Baseline that covers 0BA6 commissioning and most FBD/LAD programs. No web server UI. |
| V7.0 - V7.4 | 0BA6, 0BA7 | Adds user-defined function libraries; required for some 0BA7 firmware features. |
| V8.0 - V8.4 | 0BA6, 0BA7, 0BA8 | Recommended for new projects. Includes cloud connectivity, MQTT blocks, and the 0BA7/0BA8 web server preview. |
The current download is at Siemens Industry Online Support - LOGO! downloads. A demo of the Soft Comfort IDE is also available; the demo runs in simulation and does not need a cable to verify logic before going to the panel.
Minimum PC requirements (Soft Comfort V8.x)
- Windows 10 / 11 (64-bit); Windows Server 2016/2019/2022 supported for engineering only
- 1 GB free disk (installation footprint ~600 MB)
- USB 2.0 port or RJ45 Ethernet for the connection to the LOGO!
- Display 1280 x 768 minimum; 1920 x 1080 recommended for the FBD/LAD editor
The Siemens LOGO! product page links to the Soft Comfort download and to the LOGO! system manual. Both are required reading before any 0BA6 panel work.
Memory Card: Do You Need One?
The LOGO! memory card is a micro-SD form factor with a LOGO!-branded housing. Its real-world roles are:
- Program cloning: Copy a verified program to a fleet of identical machines without opening Soft Comfort at each station.
- Program protection: A program can be marked "copy-protected" in Soft Comfort; without the matching memory card, the project cannot be lifted off the device (the memory card becomes a hardware dongle).
- Field update path: Power-on with a card inserted causes the LOGO! to load the program from the card into working memory.
For a single 0BA6 running a one-off machine where the program was written in Soft Comfort and is not commercially sensitive, the memory card is not required. The program lives in the LOGO!'s internal flash and survives power cycles without any card.
Memory card variants
| Card | Use |
|---|---|
| LOGO! Memory Card (program storage, color yellow/green) | General program cloning and update path. |
| LOGO! Battery Card (color black/red, has a CR2032 holder) | Program storage plus retentive data and RTC backup - covers the same use cases as the memory card. |
| LOGO! Combined Memory + Battery Card | Single slot solution; the card provides program cloning and extends the on-board backup beyond 80 h. |
Battery Card: The 80-Hour Backup Limit
Without any card inserted, the LOGO! 0BA6 retains the program in flash and retains the real-time clock and retentive flags/counters/timers in a super-capacitor-buffered RAM. The published super-cap retention time is 80 hours (per the LOGO! 0BA6 system manual). After that:
- Program: Not lost. The program is in flash and is unaffected by the super-cap.
- Retentive data: Lost. Any flag, counter, or timer set as "retain" in the program falls back to its default value (0).
- Real-time clock: Reset. After re-applying power, the clock starts at the project default (typically 00:00, 01.01.2000) and must be re-set manually or via Soft Comfort.
If the panel is in a location where power is lost for longer than 80 h, or where retentive data is the whole point of the application (e.g. shift counters, totalizers, last-state flags, astronomical clock offsets), the LOGO! battery card is the correct accessory. The card contains a user-replaceable CR2032 cell and extends RTC and retentive data retention to the cell's life, which is typically 2 years with the LOGO! in continuous power and up to 4 years with the LOGO! unpowered.
Battery card part numbers and equivalents
| Accessory | Order number | Notes |
|---|---|---|
| LOGO! Battery Card (program + backup, CR2032) | 6ED1 056-1BA00-0BA0 (gen.) / 6ED1 056-1BA00-0BA8 (latest) | Direct fit to the 0BA6/0BA7 card slot. |
| Replacement cell | CR2032 3 V lithium | Panasonic, Renata, or Varta industrial grade recommended for warm installations. |
Retentive Data and Real-Time Clock Behavior
Three time sources need to be tracked separately in a LOGO! 0BA6 design:
| Quantity | Storage | Without battery card | With battery card |
|---|---|---|---|
| User program | Flash | Survives indefinitely | Survives indefinitely |
| Retentive flags / counters / timers | Super-cap-buffered SRAM | ~80 h on power loss | Battery life (years) |
| Real-time clock | Super-cap-buffered RTC | ~80 h, then resets | Battery life (years) |
For astronomical-clock-style applications (lighting control based on sunrise/sunset) the time-of-day loss is often the dominant failure mode, and a battery card is the right fix. For pure combinational logic with no timers, the loss of retentive data is harmless and no card is needed.
On-Device Programming Without a PC
The LOGO! 0BA6 has a six-key keypad and a six-line backlit LCD. The cursor keys plus OK and ESC can be used to enter an FBD program directly on the device. The use cases are limited:
- Diagnose an existing program (view blocks, jump to references).
- Edit a parameter at runtime (threshold, time base).
- Enter a trivial program of a few blocks during commissioning.
For a 100-block program the on-device editor is several hours of work; Soft Comfort is the right tool. The keypad is, however, very useful as a runtime parameter editor when Soft Comfort is on a different floor.
Step-by-Step: First Commissioning of a 0BA6
- Mount and power. Snap the LOGO! 0BA6 onto a 35 mm DIN rail. Apply 115/230 V AC (or 12/24 V DC on the appropriate variant) to the L1/N (or +/−) terminals. The unit powers up to the "LOGO! > no program" state.
- Decide on a card. If retentive data + RTC must survive > 80 h of power loss, insert a battery card with a fresh CR2032. If only program cloning will be needed later, leave the slot empty for now.
- Install Soft Comfort. Download LOGO! Soft Comfort V8.0 or later from Siemens support. Start the IDE.
-
Connect. Use either the USB programming cable (article referenced at support entry 27609308) or a Cat5 patch cable to the RJ45 LAN port. In Soft Comfort, choose Tools → Transfer → PC ↔ LOGO! and select the correct COM port (USB cable) or the LOGO!'s IP address (Ethernet). The default IP of an out-of-the-box 0BA6 is
192.168.0.10with mask255.255.255.0. -
Author the program. Use FBD or LAD view. Save the project as
project1.lsc. - Compile and download. Click Tools → Transfer → PC ↔ LOGO! → Download. The progress bar should show 100% and the LOGO! should be in RUN within two seconds.
- Verify. Toggle inputs in Soft Comfort's online view (View → Online Test) and watch outputs change. Force a power cycle and confirm the program comes back in RUN (not STOP) within 1-2 s.
- Set the clock. If a battery card is fitted, this is a one-time step; if not, plan to re-set after every long power-down via Soft Comfort or the on-device menu.
- Document. Print the FBD and the I/O assignment to the cabinet door. Cross-reference terminal labels to the Soft Comfort symbol table.
Verification Checklist
- LOGO! powers up to RUN within 2 s of power being applied.
- Status LEDs reflect input states within 50 ms of contact closure.
- Outputs toggle as expected; inductive loads (contactors, solenoids) are suppressed with RC snubbers or varistors at the coil.
- Cycle power for > 5 s, repeat; program should re-enter RUN every time.
- If a battery card is fitted: power down for 2 min, power up; RTC and retentive counters should be intact.
- If a memory card is fitted: pull the card, power-cycle, re-insert the card; the program should re-load from the card automatically (with the Card ↔ LOGO! load-on-powerup option enabled in Soft Comfort).
Troubleshooting Matrix
| Symptom | Likely cause | Fix |
|---|---|---|
| Soft Comfort reports "No connection to LOGO!" over USB | Wrong COM port selected; cable driver not enumerated; defective substitute cable | Check Windows Device Manager for the COM port added by the cable; select that COM port in Soft Comfort. Replace the cable with the genuine Siemens USB cable. |
| Soft Comfort reports "No connection to LOGO!" over Ethernet | IP mismatch, firewall, or LOGO! in a different subnet | Set the PC to 192.168.0.1/24 and ping the LOGO!. Allow Soft Comfort through Windows Firewall. |
| LOGO! boots to "no program" after power cycle | Defective memory card pulled the program; battery card has a dead cell and corrupted the card; copy-protection flagged | Re-download from Soft Comfort. Replace the card if corrupt. |
| RTC resets to 00:00 after every power-down | No battery card; 80 h limit exceeded | Fit a battery card. Re-set the clock via Soft Comfort. |
| Retentive counters zeroed on power-up | No battery card; 80 h limit exceeded; flag not marked "retain" in the program | Open the program in Soft Comfort, mark the relevant flag/counter/timer block as retentive. Fit a battery card if retention time is the issue. |
| Card write errors in Soft Comfort | Card full; card removed mid-write; card not LOGO!-branded | Re-format the card via Soft Comfort's Card → Format menu. Use only Siemens LOGO! memory and battery cards. |
| Slow transfer (> 30 s for a 200-block program) | Baud rate on RS232 cable is 9600, or the wrong IP route is being used | Use the USB cable or Ethernet. Soft Comfort tops out at 115200 on RS232 and 12 Mbit/s on the LAN port. |
Accessory Specification Summary
| Parameter | Value |
|---|---|
| Program storage without card | Flash, indefinite |
| Retentive data retention without card | ~80 h on super-cap |
| Retentive data retention with battery card | 2-4 years (CR2032) |
| Real-time clock accuracy | ± 2 s/day typical at 25 °C |
| Maximum program size (0BA6) | 400 function blocks, 8 000 bytes program memory |
| Supported memory card size | Up to 32 GB micro-SD in LOGO!-branded housing (most LOGO! projects are < 1 MB) |
| Programming cable length | USB: 3 m typical; RS232: 5 m max; Ethernet: 100 m per segment |
| Soft Comfort minimum version for 0BA6 | V6.0 |
| Soft Comfort recommended version | V8.2 |
Frequently Asked Questions
Do I really need a LOGO! memory card to use the 6ED1052-1FB00-0BA6?
No. The 0BA6 stores the program in internal flash and will run it across power cycles without a card. A memory card is only needed if you want to clone the program to other LOGO!s, protect the program with a hardware dongle, or update firmware in the field.
What cable connects a PC to the LOGO! 0BA6?
The recommended cable is the Siemens LOGO! USB programming cable, documented at Siemens support entry 27609308. A legacy RS232 cable still works on PCs with a real COM port, and a standard RJ45 patch cable works over the LOGO!'s built-in LAN port on both 0BA6 and 0BA7.
When is the LOGO! battery card mandatory?
When retentive data (counters, flags, timers marked "retain") or the real-time clock must survive a power loss longer than ~80 hours. The card extends RTC and retentive data retention to the life of the user-replaceable CR2032 cell, typically 2-4 years.
Can I program a 0BA6 without any cable at all?
Yes, using the on-device cursor keys and the built-in FBD editor. This is practical for very small programs of a few blocks and for runtime parameter edits, but is not the right tool for anything beyond a trivial sequence. Use LOGO! Soft Comfort V6.0 or later on a PC for development.
Does a 0BA6 project load into a 0BA7?
Yes, projects authored in Soft Comfort V6.0 - V8.1 are compatible across the 0BA6 and 0BA7 generations. Projects saved in V8.2+ using 0BA7-only blocks (cloud, MQTT) will not load into a 0BA6. Save the project in V8.1 for cross-generation portability.