Introduction
A packaging line engineer once faced a costly problem: a small control panel needed 26 I/O points, real-time scheduling, and a display, but a full PLC was over budget and oversized. The Schneider SR3B261JD solves exactly that challenge. This Zelio Logic modular smart relay packs 26 I/O points, an integrated real-time clock, and an LCD with navigation buttons into a compact 90 × 124.6 × 59.5 mm housing. It runs on a 12V DC supply (10.4–14.4V) and mounts on a standard 35 mm DIN rail. For machine builders replacing aging relay logic, this smart relay offers a practical upgrade path with minimal panel redesign.
Key Parameters That Matter
The SR3B261JD provides 16 digital inputs, six of which you can configure as analog inputs (12V DC, IEC 61131-2 Type 1). Ten relay outputs handle 5 A per output, enough for direct control of contactors, valves, and indicator lamps. The integrated real-time clock enables time-based scheduling without external timers. Program memory covers 240 lines of ladder logic or 500 FBD blocks, which suits small to medium automation tasks. Relay output life is rated at 10,000,000 mechanical cycles and 500,000 electrical cycles (AC-12, 230V 1.5A, IEC 60947-5-1). The operating temperature range of -20 to 55 °C supports use in most industrial cabinets. Communication is available via extension modules, so the relay can grow with your application.
Where the SR3B261JD Fits
Building automation panels. The real-time clock and 12V DC supply suit lighting schedules, pump cycling, and HVAC damper control. Six analog-capable inputs accept sensor signals without extra hardware.
Small machine control. A labeling machine or conveyor diverter often needs 10–20 I/O points. The 10 relay outputs at 5 A each can drive small motors and solenoids directly, reducing component count.
Replacement of hardwired relay banks. When a panel full of timers and relays becomes a maintenance burden, this smart relay consolidates the logic into one DIN-rail device. The ladder and FBD programming options let technicians migrate existing logic without learning a new language.
Installation and Setup
Mount the SR3B261JD on a 35 mm DIN rail inside a suitable enclosure. Connect the 12V DC supply within the 10.4–14.4V range. Wire digital inputs according to IEC 61131-2 Type 1 requirements. Relay outputs accept loads up to 5 A per point; verify the load type and inrush current against the output rating. Use the LCD and navigation buttons for on-site configuration and monitoring. For communication or additional I/O, add compatible extension modules from the Zelio Logic range. Follow Schneider Electric’s installation documentation for terminal assignments and wiring details.
Maintenance and Long-Term Value
Relay outputs are the primary wear point. The 10,000,000-cycle mechanical life and 500,000-cycle electrical life (AC-12, 230V 1.5A) give a clear basis for preventive replacement planning. Inspect terminals periodically for tightness and signs of overheating. Keep the enclosure within the -20 to 55 °C operating range and protect the device from conductive dust and moisture. Because the SR3B261JD is active in production within the Zelio Logic range, spare units and compatible extension modules remain available, which supports long-term panel standardization.
Compatibility and Integration
The SR3B261JD integrates into existing control panels through its DIN-rail mounting and 12V DC supply. It communicates via extension modules, allowing connection to broader control architectures as needs grow. The ladder and FBD programming environment aligns with common industrial programming practices, so maintenance teams can support the device without specialized training. Verify extension module compatibility with your specific application before ordering.
Selection Checklist
Before purchasing, confirm your I/O count (16 inputs, 10 relay outputs), supply voltage (12V DC), and panel space (90 × 124.6 × 59.5 mm). Check that your loads fall within the 5 A per output rating. If you need communication or extra I/O, plan for extension modules. SpareTechPLC supplies the SR3B261JD and can help verify current lifecycle status and availability before you order.
