If the PCD3.Mxx7 or PCD2.M5547 has a Profibus configuration it goes often in Stop after startup

FAQ #101176

 

Problem
If there is a Profibus configuration on the PCD3.Mxxx or on the PCD2.M5547 the CPU goes often in STOP after startup. On a older CPU the same project worked without problems.

Reason
The new systems are faster than the old ones. Therefore it happens quite often that the CPU is already in RUN and the Profibus is not yet ready. Therefore the CPU goes in STOP.

Solution
To avoid this problem we recommend programming the OB86. In case of a Profibus error this OB is called and the CPU does not go into STOP.