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Entry type: FAQ Entry ID: 21931689, Entry date: 08/29/2005

Using the IP242B in S7-400 with high-speed CPUs

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What should you watch out for when using the IP242B in S7-400 with high-speed CPUs?

The FC185 block is the standard block in the IP242B counter module for reading the counter statues of the SIMATIC S7-400 quickly.

The FC185 with the new S7 CPUs (e.g. 6ES7 417-4XL04-0AB0) does not read the counter statuses and sets the MELD parameter to A2.

  • Bit 7 = 1 collective error bit
  • Bit 5 = 1 module error
  • Bit 1 = 1 loop monitor

The FC185 has been changed. The 2 ms wait for an acknowledge from the IP242B is now monitored by means of SCF64 "TIME_TCK". This solution makes the FC185 independent of the CPU runtime commands.

The FC185 is compiled with the identifier "KNOW HOW Protection + Standard Block" and is assigned version 1.1.

The FC185 is supplied with the S7 program for the S7 project "IP_FC185" in the form of a PKZip 4.0 archive (ip_fc185.zip) and can be extracted using the SIMATIC MANAGER.

The FC185 V1.0 block in the "ip242bli" library and in the "ip242bex" example has to be replaced by the new FC185 V1.1 from the S7 program for the S7 project "IP_FC185".

FC185 V1.1 ( 25 KB )

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