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Entry type: FAQ, Entry ID: 89852601, Entry date: 04/04/2016

SINAMICS G120/G120C/G120D/G120P (CU2x0x-2): Freely interconnected bus failure bit (r2043)

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  • Associated product(s)
If the bus fails when entering a setpoint, e.g. via PROFIBUS or PROFINET, the bus failure bit should be able to be freely interconnected. Such a bit is available in parameter r2043.

How can a setpoint failure for PROFIBUS or PROFINET communication be detected?

The bus can be monitored using the "Setpoint failure" signal (r2043 bit 0), and when the setpoints fail, a response specific for the application can be initiated.

Parameter Description Bit Signal name 1 signal 0 signal
r2043 Displays the PROFIdrive PZD state 00 Setpoint failure Yes No
02 Fieldbus operational Yes No

Application example
The "Setpoint failure" bit is to be used for "remote/local" switchover (command data set switchover CDS).
For this purpose, p0810 (or p0811) should be interconnected as follows:

Parameter Description Value Result
p0810 Command data set selection CDS bit 0 r2043.0 If the bus fails, an automatic switchover is made to the command data set* for "local control".
* This command data set must be appropriately parameterized using macros (see operating instructions, Chapter Installation), or parameter.

Fieldbus communication errors
When the bus fails, the converter outputs fieldbus communication errors:

For SINAMICS G120/G120C/G120D/G120P with PROFIBUS interface:

  • F01910 fieldbus interface setpoint timeout
  • F07220 drive: Control by PLC missing

For SINAMICS G120/G120C/G120D/G120P with PROFINET interface:

  • F08501 PROFINET: Setpoint timeout
  • F07220 drive: Control by PLC missing

When the bus fails, in order that the converter does not display any fieldbus communication errors, but only switches over to "local control", and when there is an ON command, continues to run in "local control", the fieldbus communication errors can be hidden.
You can find out how to do this in FAQ, Entry ID: 70891736.

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