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Entry type: FAQ Entry ID: 109481852, Entry date: 08/18/2016

What should you watch for with configuration control (option handling) with fail-safe controllers S7-1200 and S7-1500?

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  • Associated product(s)
With configuration control (option handling) with F modules additional diagnostics are offered.

This FAQ response is valid for use of the following products:

  • Fail-safe controllers S7-1200 and S7-1500
  • Options packages STEP 7 Safety Basic (V13 and higher) and STEP 7 Safety Advanced (V13 and higher)
  • F modules of the distributed IO ET 200
  • Central use of F modules(S7-1200, S7-1500 and ET 200SP)

Use of the configuration control requires that all configurations are configured together in the TIA Portal. When using fail-safe modules of the ET 200SP and ET 200MP, you must also pay attention to the following:

You have to assign the F target address to the F modules at the designated slots. This is stored permanently on the coding element of the fail-safe modules ET 200SP and ET 200MP. You have to slot the F modules each in their configured slot. With F modules of the ET 200MP all the neighboring F modules of the station must also be slotted.
The Base Units of the ET 200SP and the front connector of the ET 200MP have to be replugged together with the coding element. Finally, there can be a difference between the physical setup and the configured setup.

The behavior described below applies generally for the use of F IOs:

A flashing (red) of the SF LED on the interface module of the station on the F CPU does not automatically indicate an error, but also indicates the disabling of one or multiple F modules in a distributed/central station (use of the configuration control). The requirement is that the F IOs are also addressed in the F program. There is also an entry in the diagnostics buffer.

Diagnostics buffer entry and LED flashing occur independently of any possible change of the physical setup. The SF LED stops flashing when the disabled F modules are re-enabled.

The statements below are also valid for using a fail-safe S7-1200 controller with central F modules.

  • The following setup rule holds for F modules and standard modules:
    The S7-1200 F-CPU must be followed by the F modules and then the standard modules.
  • Configuration control is only possible with standard modules. You must not change the configuration of the F modules.

Further Information
Detailed information on the topic of "Assignment of the F target address" is available in the Programming and Operating Manual "SIMATIC Safety - Configuring and Programming" in Entry ID 54110126

A sample application for the topic of configuration control is available in Entry ID 29430270

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