Safety field box SFB-IOP for I/O devices
Free interlinking of safety switchgear devices
Cost-effective and fail-safe installation
Integrated web server for displaying status and diagnostic data

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Simple installation solution for complex machines: safety field box with field bus interface

The SFB safety field box allows simple plug-and-play installation of up to eight safety devices per box, with interface for higher end field bus.

Thanks to its universal device interface with an 8-pole M12 connector, it can be used to connect a wide variety of safety devices: electronic and electro-mechanical safety interlocks, switches, sensors, light curtains and operation panels. Field box device connections can also be configured to link different devices, thus providing maximum flexibility in the conceptual design of safety solutions.

The safety signals from connected safety devices are forwarded to a safety controller for evaluation. Parallel transmission of safety signals allows safety devices to be freely linked in the safety controller. 

All device connections also feature a self-resetting fuse element to protect lines. After eliminating an overcurrent in a connection, the fuse element resets itself after a brief cool-down period.


Features of the safety field box

  • Installation of up to 8 safety switchgear devices
  • Optimum process transparency through transfer of all diagnostic signals from connected devices to the control system. A digital input is available on each device socket.
  • Field bus interfaces:
    • PROFINET / PROFIsafe
    • EtherNet IP / CIP Safety
    • EtherCat / Safety over EtherCat (coming October 2023)
  • M12 power connector with 10 A current capacity for installation of wide range of safety systems
  • Connect a wide variety of safety devices:
    – Electronic safety sensors with p-type semiconductor outputs (OSSD)
    – Electronic solenoid interlocks with p-type semiconductor outputs (OSSD) and 1- or 2-channel actuation of interlock function
    – Active opto-electronic protective devices (AOPD), such as safety light curtains and light grids
    – Control panels with electronic E-STOP function and non-safe command and signaling devices (max 4)
    – Safety switches and reed sensors with 2 NC contacts
    – Solenoid interlocks with 2 NC contacts and 1-channel solenoid control up to 0.8 A
  • Plug-and-play installation with Universal M12 device sockets and available connection cables:
    - Power to SFB cable, M12 connection to leads, various lengths
    - Controller to SFB communication cable, RJ45 to M12 connection, various lengths
    - Device connection cables, double ended M12 8-pole connections, various lengths
  • Series chain up to 10 safety field boxes:
    - SFB to SFB power cables, double ended M12 4-pole connections, various lengths
    - SFB to SFB Ethernet cables, double ended M12 4-pole connections, various lengths
  • LED status indicators:
    - 2 on each connection port, shows power and input status
    - additional LEDs for overall SFB status
  • Line protection with integrated automatic resettable fuses for all device connections.
  • Robust, industrial design:
    – Fiberglass reinforced thermoplastic enclosure
    – Protection class IP67
    – Operating temperature range –20 °C to +55 °C
    – cULus Approval
  • Wide range of accessories available, including port labels and protective covers for unused ports.


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