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Entry type: Application example Entry ID: 53842953, Entry date: 11/23/2015

Calculation and Design of Fieldbus Segments with the SIMATIC Fieldbus Calculator

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  • Associated product(s)
Segment configurations can be designed and optimized using the SIMATIC Fieldbus Calculator, based on SIMATIC fieldbus components such as field distributors, Compact FF Links and couplers.

SIMATIC PCS 7 is based on a consistent architecture. This architecture enables the integration of devices using different types of communication.
Apart from the conventional the 4 - 20 mA communication scheme (optionally with HART protocol), the fieldbuses PROFIBUS PA and FOUNDATION Fieldbus H1 are also widely used in the area of process automation. 

The successful planning of fieldbus segments requires to find an optimum combination with regard to the area of application, quantity framework and topology. Furthermore, the physical and system-specific requirements and restrictions (number of devices, length of lines, topology) must be taken into account.

The SIMATIC Fieldbus Calculator assists the user in the planning and laying out of fieldbus segments.

Figure 01: Application example of the SIMATIC Fieldbus Calculator

The relevant physical data (line lengths, basic current of the devices, topology, etc.) for each fieldbus segment are entered. Based on the defined configuration, the SIMATIC Fieldbus Calculator then calculates the electrical values and issues a warning, if limits are violated.

The solution presented here offers the following advantages:

  • Free use of the tool
  • Flexible planning of the fieldbus segments through the modification of line lengths and shifting of field devices.
  • Information if the electrical values exceed the defined limits.
  • The existing configurations can be checked and expanded, if required.

The SIMATIC Fieldbus Calculator is used for the calculation of fieldbus segments which are supplied with power by a fieldbus coupler and equipped with AFD (Active Field Distributor) and AFDiS (Active Field Distributor intrinsic Safety). The following types of fieldbus couplers / bundles can be used:

  • DP/PA coupler (order number 6ES7157-0AC83-0XA0)
  • Field device coupler FDC 157 (order number 6ES7157-0AC84-0XA0)
  • Field device coupler FDC 157 (order number 6ES7157-0AC85-0XA0)
  • Compact FF link (order number 6ES7655-5BA00-0XA0)

The structure is based on

  • AFD (Active Field Distributor)
  • AFDiS (Active Field Distributor intrinsic Safety)
  • AFDiSD (Active Field Distributor intrinsic Safety Diagnostic

This entry was created with SIMATIC PCS 7 V8.1, the procedure is valid for PCS 7 V8.2 and higher versions.

Documentation and Calculation tool
  Documentation (2,1 MB)
 Registrierung notwendig  SIMATIC Fieldbus Calculator (1,1 MB)

Further Information
Application example - Configuration of FOUNDATION Fieldbus H1 (FF) with SIMATIC PCS 7
Application example - SIMATIC PCS 7 with PROFINET – Typical Architectures and Engineering

Last modification
Support of new hardware Compact FF Link and AFDiSD. Calculation tool based on .NET Framework.

Additional keywords
PA, FF, fieldbus trunk, fieldbus segment, quantity framework, DP/PA link, PA ring, bus length, termination, field device, Redundancy, Stub line length,  Active Field Distributors, FF coupler


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