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Entry type: Product note Entry ID: 109749357, Entry date: 07/11/2018

Smart field distributor – SIMATIC Compact Field Unit

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The SIMATIC Compact Field Unit is released for delivery.

Digitalization is an important catalyst for the process industry. When developing SIMATIC PCS 7 V9.0 – the new version of the proven SIMATIC PCS 7 process control system – the emphasis was placed on a forward-looking approach to the possibilities of digitalization, down to the field level. For that reason, the system solution has been extended by particularly powerful and compact hardware products that are compatible with PROFINET, the world's leading Industrial Ethernet standard, that free up resources for enhanced plant planning and operation.
With the new SIMATIC Compact Field Unit (CFU), we are reinterpreting the conventional approach to field device connection. This means that you benefit from greater flexibility and ease of use, together with the highest availability, allowing you to efficiently transfer your trusted system concept into the digital world.

Today's challenges in field device connection

  • High overhead for device integration and replacement
  • Complicated, error-prone wiring and marshalling over several levels, making the hardware FAT very complex
  • Very long copper cable spanning and a lot of clamping points in the field
  • A myriad of individual control cabinets
  • Large numbers of different components and protocols necessitate costly spare parts inventories and training sessions
  • High planning and documentation costs

1. SIMATIC CFU – the response to these requirements

How it works

Field device connection with previous technology (left) and with SIMATIC CFU (right)

The new SIMATIC Compact Field Unit (CFU) is a real game-changer in field device connection and offers you entirely new prospects regarding simplicity and flexibility. 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. Utilization of digital fieldbus communication simplifies device interfacing considerably compared to conventional 4 - 20 mA engineering.

Plug-and-produce simplicity

Digitalization requires a digital infrastructure facilitating integrated digital communication down to the field level. This can be built up using the standard, tried and tested PROFIBUS PA. This is integrated into the PA Edition of the SIMATIC CFU, thus combining ruggedness and easy handling with all the advantages of the PROFINET standard based on Industrial Ethernet. Connected devices are automatically addressed. The device is integrated via standardized communication profiles.

This completely innovative implementation of the PROFIBUS PA concept makes it possible to combine the simplicity of a point-to-point wiring system with the scalability of digital PROFIBUS PA fieldbus communication. As with digital field devices, it is not necessary to know whether the discrete field device is a sensor or actuator prior to connection. This can be conveniently configured afterwards via software.

More versatility due to consistent decentralization

Due to the distributed installation of the SIMATIC CFU, classic control cabinets are no longer required and you can benefit from the considerable savings in cabling and the number of terminal points as well as the reduction of overhead for planning and documentation. The high granularity (16 I/O per SIMATIC CFU) enables flexible assignment to the higher-level controllers.


The SIMATIC CFU was specifically designed to meet the requirements of the process industry in the Industrie 4.0 environment (in this example: SIMATIC CFU in a standard aluminum field enclosure).

System interfacing via Industrial Ethernet standard

  • Redundant PROFINET connection (S2) for the highest degree of availability
  • Connection versatility with PROFINET
  • BusAdapter (for example electrical, optical or mixed)

Combination of digital fieldbus and discrete I/O

  • 8 × digital fieldbus (PROFIBUS PA)

  • 8 × digital inputs/outputs, freely configurable   

Ready for distributed

  • Installation in hazardous areas up to zone 2/22 (with conformal housing)

  • Extended temperature range from -40 to +70 °C

  • Conformal coating

  • Use at altitudes up to 4000 meters

  • Enhanced interference immunity according to NAMUR NE21       

  • Optional: Aluminum housing for direct field use up to zone 2/22

Easy to use

  • Automatic addressing of PROFIBUS PA field devices

  • System-supported detection and integration of PROFIBUS PA field devices into the process control system

  • Utilization of standardized PA profiles
  • Commissioning, device exchange and maintenance wizards
  • Implementation of diagnostic messages according to NAMUR NE 107

  • 35 mm standard rail mounting

2. Components


SIMATIC CFU PA: in this case with Bus Adapter, PROFINET bus cable and push-in terminals

  • 16 x I/O Channels

  • PROFINET interface V2.3 (RT)

  • Use of PROFINET BusAdapter

  • Media redundancy (MRP)

  • PROFINET system redundancy (S2)

  • Configuration in RUN (CiR)

  • Process interfaces:

    • 8 x PROFIBUS PA (with plug-and-produce)

    • 8 x freely configurable DIQ

  • Installation up to Ex zone 2

  • Temperature range from -40 to +70 °C

  • Conformal coating

  • 35 mm standard rail mounting

  • Available in an aluminum housing                

The corresponding terminals are also required for the use of the SIMATIC CFU. The terminals are already included in the SIMATIC CFU PA Bundle and SIMATIC CFU PA Bundle with aluminum housing.

ProductArticle number
SIMAITC CFU PA Bundle with aluminum housing6ES7655-5PX11-1AX0 
BusAdapter 2xRJ456DL1193-6AR00-0AA0
BusAdapter 2xFC6DL1193-6AF00-0AA0
BusAdapter 2xLC6DL1193-6AG00-0AA0

3. Highlights of the SIMATIC CFU at a glance

Plug-and-produce simplicity

  • Fast, fail-safe device integration 
  • Safe and simple device replacement without work in the engineering system

    The related time expenditure is reduced from at least 30 minutes to approx. one minute.

More versatility due to consistent decentralization

  • No more individualized control cabinets

  • Reduction in marshalling and cabling costs

  • Lower planning and documentation costs 

  • Standardized design – no hardware FAT required

  • Parallelization of project processes

  • Flexible plant expansion without the need to stock spares

  • Reduced complexity and lower installation and maintenance costs
    This means up to 70 % fewer terminal points required as well as a reduction in cabling by 30 % or more.

4. Configuring

The SIMATIC CFU has been tested and approved for use with the automation system SIMATIC CPU-410 and complementary SIMATIC S7-400 systems. Configuration is carried out in the following SW environments:

System integration

  • SIMATIC PCS 7 V9.0 and higher
    The following HUP is required for the SIMATIC CFU in SIMATIC PCS 7 V9.0:


Firmware Versions
SIMATIC CFU Firmware Versions:
Entry ID 109754628

It is recommended to upgrade to current Firmware Version.

Further system integration

5. Documentation

The documentation for the SIMATIC CFU includes the following documents:

ManualEntry ID
Commissioning Manual: Distributed I/O SIMATIC CFU109759420 
Automation systems, Principles of Explosion Protection12521844

Application examplesEntry ID
Easy and flexible device integration with SIMATIC CFU          109758252 
Integration of SIMATIC CFU in the TIA Portal109766570 

6. Additional information

You can find more information about SIMATIC CFU at www.siemens.com/pcs7 and www.siemens.com/pcs7-v9

Flyer: SIMATIC Compact Field Unit

PROFINET in Process Automation with SIMATIC PCS 7:
See entry ID 72887082

You can also contact your SIMATIC partner at your local Siemens office (Siemens partners on the Internet). These pages can also be saved locally as an offline version.

Security information
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