Powerful and compact distributed I/O for the process industry

USA | PCS 7 Distributed I/O

Process I/O: The right solution for every requirement

Today, the acquisition and output of process signals via sensors and actuators can take place in a variety of ways: centrally or decentrally, inside or outside switch cabinets, with or without connected drive technology, etc. SIMATIC PCS 7 offers a wide range of options for integrating the process data in the best possible way: Either remotely via signal and function modules in remote I/O stations on the fieldbus or centrally using analog I/O modules operating in the automation system. 

As individual as your requirements

Process I/O made to measure

Flexible, decentralized solutions are the state of the art in automation today. Whether compact or modular, purely digital I/O interfaces, or complete decentralized systems including integrated drive technology; installed in the control cabinet or directly in a harsh industrial environment - SIMATIC hardware for the process industry offers the right solution for every application and corresponding options for connecting field devices.

Process control technology from Siemens paves the way for plant-wide digitalization. By supporting PROFINET, our innovative hardware not only bridges the communication gap into the field level - but also from today into the future. A solid automation platform is the perfect basis for investment protection. The distributed SIMATIC I/O systems offer high planning reliability for up to 30 years. Standards are the prerequisite for compatibility and promote broad acceptance in various areas of the process industry.

  • Fully compatible successor products enable easy replacement
  • Fast and simple functional expansion is permanently guaranteed
  • Seamless reuse of existing modules and cabling


The SIMATIC ET 200 product family has always been a guarantee for powerful and distributed solutions that can be individually adapted to any automation requirement. The I/O system is ready for use inside and outside the control cabinet and can be expanded in small steps: Modules for digital and analog inputs/outputs, safety technology, motor starters, frequency inverters and other technology modules ensure that you can equip your I/O system with the appropriate signal and function modules.


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Enclosed space in a plant is a scarce commodity. And expensive. Our answer is SIMATIC ET 200SP HA! The compact modular I/O creates space in the control cabinet and offers plant planners and operators advantages. Their highly scalable design makes it possible to align the expansion in the control cabinet exactly with the actual requirements. And the tool-free connection technology with push-in terminals and vertical wiring reduces engineering, assembly and cabling costs. SIMATIC ET 200SP HA compact design, saves costs for enclosed space and for air conditioning, energy requirements, etc. for the I/O in the control cabinet. Thanks to its extended temperature range from -40°C to +70°C and conformal coating, the I/O system is ideally suited for use in the field. Further advantages: Change in run through redundant design and increase in the number of modules at the head-end station from 12 to 56.


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Learn more about SIMATIC ET 200SP HA

The SIMATIC ET 200iSP decentralized I/O system is the economical solution for hazardous areas. The intrinsically safe and modular I/O is particularly flexible and low-cost for engineering, assembly and cabling. The I/O system is mainly used in the process industry and allows optimum integration into SIMATIC PCS 7 and other control systems. Intrinsically safe I/O may be directly installed in potentially explosive gas and dust atmospheres, i.e. in zones 1 and 2 as well as 21 and 22; sensors and actuators can be located directly in zones 0 and 20. Extensive standards and approvals are available for the SIMATIC ET 200iSP.


Flyer "SIMATIC ET 200iSP The Field Mounted Solution for Hazardous Areas"


Flyer "Stainless Steel Wall Enclosure for SIMATIC ET 200iSP Individual and Turnkey Ready Solutions"

Within the ET 200 family, ET 200M represents the main line of distributed I/O systems for process control applications with SIMATIC PCS 7. SIMATIC ET 200M offers the greatest benefits for complex user-specific automation tasks. The system comprises a wide range of I/O modules based on S7-300 technology, including special control functions. If active bus modules are used, defective peripheral modules can be replaced while the plant is running without affecting neighboring modules. A fast and safe connection of field devices to the I/O modules of the ET 200M remote I/O stations can be made via so-called terminal modules MTA (Marshalled Termination Assemblies). With their help, the effort and costs for cabling and commissioning can be significantly reduced and wiring errors avoided.


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With the SIMATIC CFU (Compact Field Unit), the previously very complex integration of field devices is easier than ever. You benefit from greater flexibility and easier handling coupled with maximum availability.


Ready for game-changing innovations at the field level? Transfer your familiar plant concept efficiently to the digital world. The compact field distributor is installed at the process level and is connected via PROFINET directly to the process control system to form the foundation for digitalization in the field.


The SIMATIC CFU combines a digital fieldbus with conventional I/Os and is suitable for use directly in the field, as far as hazardous zone 2. This significantly reduces the footprint of the entire I/O system: Conventional control cabinets are a thing of the past and significant savings can be made with regard to cables and terminals, as well as in the planning and documentation work. The device reduces the potential for errors during operation, simplifies plant expansions or modernization, and reduces the amount of work required for the hardware FAT.

The PA edition of the SIMATIC CFU combines the ruggedness and simplified handling of the PROFIBUS PA communication standard with all the advantages of the PROFINET standard based on Industrial Ethernet. This compact hardware innovation automatically initializes connected field devices and integrates them into the process control system. What used to take 30 minutes is now done in less than one minute. That's Plug-and-Produce!


You can find more information in our flyer

The SIMATIC CFU DIQ edition meets the requirements of digital transformation for the distributed I/O: Sixteen freely configurable, digital I/O channels and optional extension functions offer you even more flexibility and easier handling coupled with maximum availability.

The additional operating modes "Counter" and "Frequency measurement" can be activated for selected digital inputs. In addition, the safety function "Actuator disconnection" can be set for the digital outputs. This function enables you to bring your actuators to a safe position as required to avoid possible hazardous situations.


You can find more information in our flyer


Siemens technology modules allow the integration of SMART instrumentation. Weight and flow measurements are an integral part of any innovative, future-oriented process and production system and autonomous, stand-alone solutions are no longer acceptable in state-of-the-art plants. SIWAREX weighing modules and the SITRANS FCT070 Coriolis flow transmitter integrate seamlessly with ET 200SP distributed I/O. 


SIWAREX WP321 weighing module is used for non-automatic weighing applications such as level measurement in silos and bunkers, and platform scales. The SIWAREX 321 is seamlessly integrated into the SIMATIC PCS7 environment via the ET200SP HA. 


The high-performance SIWAREX WP351 is packed into an ultra-compact design. The SIWAREX WP351 can be used in automatic scale applications such as controlling a batching or filling process, and in checkweighing applications.  It is integrated seamlessly into the ET 200SP HA system and directly connected to SIMATIC PCS7, making it a smart alternative to a “black-box” weighing terminal.


SITRANS FCT070 lets you process data in real time and visualize all the measurement and status information from the Coriolis flow meter. Thanks to the Digital Sensor Link (DSL), SITRANS FCT070 is compatible with all Siemens Coriolis flow meters and ready for real-time data exchange.



Whether you need to produce accurate mixtures, ensure precise filling and loading, or perform tasks like bagging, checking and dosing: SIWAREX WP351 is always the right choice. It’s the perfect fit for all automatic and non-automatic weighing applications


SIWAREX WP321 is a weighing module for the distributed I/O system SIMATIC ET 200SP. Due to the diversity and the flexibility of the SIMATIC manager and TIA Portal, it is an ideal solution for small and medium automation systems.


The SITRANS FCT070 Coriolis flow transmitter is a technology module which can easily integrate Coriolis flow meters into the SIMATIC ET 200SP system and connect to SIMATIC S7 controllers. Faceplates and drivers are included for direct integration into the SIEMENS TIA Portal and SIMATIC PCS 7.

Distributed I/O, transmitters, drives, valves or operator terminals communicate with the automation systems at field level through a powerful real-time bus system. This field communication is characterized on the one hand by the cyclic transmission of process data and, on the other hand, by the exception-based transmission of alarms, parameters and diagnostic data. The universal PROFIBUS covers all of the requirements of the production and process industries and has already proven itself as a rugged and reliable communication medium at the field level.


Process engineering processes are often executed in corrosive, harmful and hazardous environments. Therefore the direct connection of transmitters and actuators, including power supply via the communication medium, as well as detailed diagnostics, is particularly relevant to the automation system. Both PROFIBUS PA and FOUNDATION Fieldbus are suitable for these requirements. Both standards can be integrated seamlessly in the SIMATIC PCS 7 process control system using PROFIBUS DP as a link.


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To create a smooth network transition between PROFIBUS DP and PROFIBUS PA, the SIMATIC product range offers two versions: the DP/PA coupler and the PA link. 


  • The DP/PA coupler is especially suitable for small quantities of signals and low timing requirements.
  • The DP/PA link is ideal for a large number of stations and high cycle time requirements

The network transition between PROFIBUS DP and FOUNDATION Fieldbus is implemented with Compact FF Links. The Compact FF Link can be operated individually or redundantly.

With conventional fieldbus installations, changes during runtime are only possible to a very limited extent. This is because short-circuits or contact bounces when connecting or replacing devices can lead to the failure of the fieldbus segment.  Fieldbus installations with active field distributors from SIMATIC permit the addition and removal of field devices and of active field distributors during operation without any disrpution.


The active field distributors (AFD) can be operated in environments up to Zone 22 and are available in different versions.


Each AFD4 model can hold up to four, and each AFD8 can hold up to eight standard-compliant field devices in a fieldbus segment with automatic bus termination.

AFDiSD (Zone 1)

AFDiSD (Active field distributors intrinsically-safe with extended fieldbus diagnostics for PROFIBUS PA segments) can be operated in environments according to hazardous zones 1/21 and 2/22. AFDiSDs can integrate up to six standard-compliant, intrinsically-safe field devices in a fieldbus segment via its intrinsically-safe, short-circuit proof spur line connections. 


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Learn more about the comprehensive range of SIMATIC I/O systems. The documents in the download area deepen certain aspects and inform you about special functions.

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