Description
The SR3B261FU is a modular smart relay from Schneider Electric’s Zelio Logic range, offering a compact, cost-effective alternative to hard-wired logic or dedicated control cards for small automation systems. It provides 26 I/O in total — 16 discrete inputs and 10 relay outputs — within a compact DIN rail-mounted housing (124.6 × 90 × 59mm), and can be expanded further with I/O extension modules and communication modules (Modbus or Ethernet) for up to 40 I/O when needed.
Programming is done via Schneider’s Zelio Soft 2 software, supporting both function block diagram (FBD, with up to 32 pre-programmed functions) and ladder logic (with 12 pre-programmed functions), making it accessible to both automation specialists and less experienced users. The relay includes a large back-lit LCD display (4 lines of 18 characters plus an icon line) with 6-button contextual navigation, allowing on-site monitoring, parameter adjustment, and diagnostics without a PC. An integrated real-time clock (10-year battery backup at 25°C) supports time-based control programs, and built-in EEPROM flash memory retains program data for up to 10 years — protecting against loss from power interruptions. Operating on a 100–240V AC supply, the SR3B261FU is well suited for control systems on small machines, building automation (lighting, access control), and general industrial or commercial automation tasks where a full PLC would be oversized for the job.