The BWU2284 is an AS‑Interface Safety at Work input module designed for field‑mounting directly on machines, combining a 2‑channel safe input and two standard outputs in a compact, robust IP67 housing. The safe input (1SI) is intended for floating contacts such as emergency‑stop buttons or safety door switches and is certified to SIL 3 (IEC 61508) / Performance Level e, Cat. 4 (EN ISO 13849‑1) when wired accordingly. It supports both 1‑channel and 2‑channel safety configurations, enabling cross‑monitoring of redundant contacts for highest safety integrity.
Peripherals connect via 4 × M12 sockets (5‑pole), typically with one M12 used for the 2‑channel safe input and the others for standard I/O and auxiliary supply distribution. The sensor supply and input electronics are powered from the ASi bus, while the two digital outputs are supplied from an external AUX power (typically 24 V DC), allowing safe separation between bus and actuator loads. The module connects to the ASi flat cable using insulation‑piercing technology and uses a single ASi address, simplifying addressing and configuration in the ASi master.
Outputs are standard (non‑safe) digital outputs intended for actuators like lamps, contactors or signal devices and are switched according to the non‑safety part of the application logic. Maximum cable length between the module and connected sensors/actuators is typically up to 15 m, providing flexibility in distributed mounting along the machine. The module supports the usual ASi diagnostic mechanisms, including detection of short circuits, cross faults and line breaks on the safe input via the safety monitor function in the ASi master.
Mechanically, the BWU2284 features a fully encapsulated IP67 housing suitable for harsh industrial environments, resistant to dust and temporary immersion, provided the M12 connectors are properly sealed. Operating temperature typically ranges up to +55 °C according to UL certification for use in the USA and Canada, covering most machine and plant environments. The device meets relevant standards for AS‑Interface, functional safety and EMC, and is part of Bihl+Wiedemann’s portfolio of Safety I/O modules for ASi networks.
Key Specifications
