
Description
The Siemens 6ED1052-1MD08-0BA0 is a LOGO! 12/24RCE logic module manufactured by Siemens, part of the LOGO! 8.2 (FS02) generation of compact intelligent logic controllers. It belongs to the category of palm-sized programmable logic modules designed for small-scale automation tasks where a full PLC/DCS is overspecified but relay-timer logic is too rigid. The module combines 8 digital inputs (4 of which are switchable to 0–10 V analog), 4 relay outputs rated at 10 A, onboard Ethernet with integrated web server, data logger, and a 400-block program memory — all in a 71.5 × 90 × 60 mm DIN-rail housing powered from 12/24 V DC.
Application Scenarios
A municipal stormwater pumping station in a mid-size German town was running on a 1990s vintage electromechanical timer panel: two 4 kW submersible pumps on duty/standby, level sensed by three float switches, and a third “alarm” pump that never seemed to trigger when it should. During a heavy autumn storm, the timer-relay sequence hung — one pump burned out on dry run because the float logic didn’t see the low-level reset, and the station overflowed into the adjacent bike path. The municipality had €12K budget, not €80K for a full S7-1200 + HMI retrofit. The contractor dropped a Siemens 6ED1052-1MD08-0BA0 into a spare 4-unit DIN slot in the existing cabinet: 12 V DC came from the station’s battery-backed supply, the three floats wired to DI1–DI3, and a 0–10 V pressure transducer on the wet well (already installed but unused on the old panel) landed on DI4 configured as analog. The 4 relay outputs drove the two pump contactors, the alarm horn, and a telemetry dry-contact to the SCADA hut 800 m away.Commissioning took one afternoon with LOGO!Soft Comfort V8.3: duty/standby alternating, pump run-hour balancing, low-level dry-run lockout with a 30-second delay (using the built-in PI-controller function block to smooth the pressure-transducer signal), and — the feature the facility manager actually uses daily — the integrated web server was enabled with a custom page showing pump status, wet-well level in %, and last-alarm timestamp. No HMI, no extra gateway: the station’s existing LAN reached the cabinet, and the manager pulls the LOGO!’s webpage on his phone. Six months later, a second storm event hit; the 6ED1052-1MD08-0BA0 caught the rising level at 82%, auto-started pump 1, brought pump 2 online at 88%, and the manager got a browser refresh showing “P2 RUN” before the first overflow alarm would have fired. Total install cost: €340 for the module + 6 hours labor. The old timer panel is now a museum piece on the workshop shelf.
Key Parameters
| Main Parameters | Value/Description |
|---|---|
| Product Model | Siemens 6ED1052-1MD08-0BA0 |
| Alternate Identifier | LOGO! 12/24RCE (LOGO! 8.2, FS02) |
| Manufacturer | Siemens AG |
| Product Category | Compact Logic Module / Smart Relay |
| Supply Voltage | 12/24 V DC (10.8–28.8 V DC range) |
| Digital Inputs | 8 (4 switchable to 0–10 V analog; 4 usable as high-speed counter up to 5 kHz) |
| Digital Outputs | 4 × relay, 10 A max (resistive), 3 A (inductive) |
| Program Memory | 400 function blocks |
| Communication | Ethernet 10/100 Mbps, integrated web server, Datalog (up to 20,000 records) |
| Storage Expansion | Standard microSD HC up to 32 GB (FAT32), for program/data/log |
| Operating Temp. | -20 °C to +55 °C |
| Dimensions (W × H × D) | 71.5 × 90 × 60 mm (4 TE width, 35 mm DIN rail) |
| Protection | IP20 (terminals), IP65 (front foil with door seal) |
| Certifications | CE, UL, CSA, FM, GL (Germanischer Lloyd), EN 61131, VDE 0631 |
| Lifecycle Status | End of Product Lifecycle (still supported, backward-compatible with Soft Comfort V8+) |
