2 Product description
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2.1.7
Module in the PROFINET system
The SFB-PN safety module is also a PROFINET IO device and a PROFIsafe
slave. It receives and sends data to and from the F-PLC in form of the PROFIsafe
telegrams. PROFIsafe telegrams are tunnelled in PROFINET standard telegrams.
(Black Channel principle)
The F-PLC processes safe input data and sends safe output data cyclically to
the PROFIsafe slave. PROFIsafe telegrams contain control and status bits.
The telegrams signal the states of masters/slaves and initiate a status change
if necessary.
The SFB-PN safety module detects errors in the module and errors in the
installation or the connected safety switching devices. After an error has been
detected in the safety section, the module returns to the safe state.
External errors are rectified by eliminating the error cause and then acknowledging
the error.
Normally, internal errors are only rectified by module replacement.
