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Entry type: Application example Entry ID: 21626985, Entry date: 06/09/2005

Calculator for the Calculation of the Connection Balance for typical Associations of an SIMATIC S7-CPU

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SIMATIC S7-CPUs perform numerous communication tasks in today’s automation systems. For this purpose, the S7-CPU needs “connections”. Each S7- CPU provides a maximum number of such connections, i.e. this number is limited. The following questions have to be answered reliably already in the concept phase of an automation project:
  • Can the planned associations be realized using the planned S7-CPU?
  • Does the S7-CPU provide a sufficient number of connections for all associations?

In order to answer the above questions we developed the “connection calculator” which can be used to quickly evaluate and calculate your possibilities. In order to operate the tool no specialized knowledge of communication is required. The principle is quite simple:

  • The intuitively operable input interface allows you to systematically enter all planned associations of the S7-CPU.
  • By means of the calculator only those associations can be entered which can actually be realized with the S7-CPU. You are thus informed on the feasibility of a planned association already when entering the data.
  • The tool up-dates the connection balance of the S7-CPU whenever an association is entered.

The separate download “Documentation” provides up-to-date information in a compact and clear way. You will also find a detailed application example for the calculator.

The below screenshot shows the user interface of the connection calculator:


Contents of the downloads


Guided Tour
Film explaining the operation of the connection calculator.

Note: The ZIP file contains a short film ( about 6 minutes). The film file is automatically started with the Windows Media Player.

German 21626985_verbindungen_MOV_v30_d.zip ( 988 KB )
Englisch 21626985_verbindungen_MOV_v30_e.zip ( 908 KB )
Tool for the calculation of the connections of a SIMATIC S7-CPU.

Note: Always activate the macros when starting Excel! For use, please download the file. When the calculator is used within the browser, there may be malfunctions.

German 21626985_verbindungen_KALK_v30_d.xls ( 1184 KB )
Englisch 21626985_verbindungen_KALK_v30_e.xls ( 1176 KB )
Detailed information on the connection calculator (about 80 pages).
German 21626985_verbindungen_DOKU_v30_d.pdf ( 900 KB )
Englisch 21626985_verbindungen_DOKU_v30_e.pdf ( 908 KB )




06/2004 First edition (V3.0)


In/out point, end point, connection type, end point relation, in/out point relation, connection resources

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