S900 I/O

S900 is a remote I/O system for mounting directly in the field and hazardous areas.

S900 provides all input and output modules needed for intrinsically safe field signal connection. The field signals are amplified in every S900 functional module, electrically isolated, and then output via an internal serial bus. A communication interface converts the digitized signals to adapt them to the standardized PROFIBUS DP-V1 fieldbus protocol. Supervisory process control systems, DCS or SCADA systems use an intrinsically safe fieldbus to communicate with the communication interface.

A single fieldbus network suffices for configuring the individual fieldbus nodes, for cyclic data exchange, for all acyclic services, and for communication with HART®-compatible field instruments. All functional modules can be replaced easily and quickly in the installation or maintenance phase. The functional modules and the – optionally redundant – communication interfaces of systems can be removed and plugged in while operation is running. This does not affect the communication of the remaining modules, even if being placed in hazardous areas such as Zone 1 or Zone 2. Only the primary power for the plug-in type power supply modules requires increased safety EEx-e.

Integrated encapsulated switch-off mechanisms allow for hotswapping, i.e. the power supply units can be replaced without interrupting the primary power. Due to its little space requirements, the robust design and its environmentally ruggedized case, the cost-saving I/O system S900 is the best solution for use on site, especially in hazardous areas such as Zone 1 or Zone 2.

Choose the right hardware

For up to date on technical data for S900 I/O, comparisons, and to generate data sheets, please visit the 800xA Hardware Selector:


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Service and Support


For S900 there are GSD files available for CI920/CI920A. You may download it from ABB Library here.

If you do not have access, do not hesitate to contact us.

It is our goal to provide the services and programs required to protect our customer’s control system investment throughout its lifecycle. From initial design, engineering and startup services, through maintenance and optimization to upgrade and evolution, we provide the programs, services and commitment necessary to ensure maximum return on investment for your system.

These valuable lifecycle programs include:

  • System Updates
  • Lifecycle Policy
  • Automation Sentinel
  • Evolution
  • Services:
    Reliablility, Full Service, Performance Services, Product Service, Remote Services
  • MyABB
  • Consult IT

Ready-made, EExi/ATEX-certified high-grade steel housings for assembly in the field provide a wide range of installation options.

Field housings – for wall-mounting in case of installation in hazardous areas such as Zone 1 or Zone 2, with a system approval fully certified in accordance with ATEX. The stainless steel field housing is ready-wired and prepared for wall-mounting. In addition, screen rails or terminals can be mounted. Together with the field housing, this brings the following advantages:

  • Complete design, heat compensation, and documentation by ABB
  • Elimination of additional marshalling units
  • Thanks to the S900 modules, no external barriers are needed for the field circuits
  • Simplified acceptance of the plant with regard to hazardous areas
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