Safety program of the F-PLC
3
3.1
Overview
Information about F-PLC, F-I/O, the safety program and/or SIMATIC Safety in this manual
serves as entry-level information only - and describes the special features relating to
SINUMERIK.
Note
Important additional information
For space reasons, the information described in this manual cannot replace a complete
SIMATIC Safety Manual.
Therefore, when configuring these safety programs, it is crucial that you carefully follow the
information provided in the TIA Portal help on SIMATIC Safety or in manual "SIMATIC Safety
- Configuring and Programming (
https://support.industry.siemens.com/cs/ww/en/view/
)".
Principle of operation of the F-PLC safety functions
The safety functions of the F-PLC are mainly implemented in the software. The safety functions
are executed by the F-system to bring the system into a safe state if a hazardous event takes
place – and maintain it in this safe state. Safety functions are contained mainly in the following
components:
● in the safety-relevant user program (safety program) in the PLC with active F-capability
(F‑PLC)
● in the failsafe inputs and outputs (F‑I/O)
● in the safety functions integrated in the drive (drive components)
The F‑I/O ensure the safe processing of field information (sensors: e.g. EMERGENCY STOP
pushbuttons, light barriers; actuators, e.g. motor controls). They have all of the required
hardware and software components for safe processing, in accordance with the required
Safety Integrity Level. The user only has to program the user safety function. The safety
function for the process itself can be implemented using a user safety function - or a fault
response function. In the event of an error, if the F-system can no longer execute its actual user
safety function, it executes the fault reaction function; for example, the associated outputs are
shut down, and the F‑PLC goes into the STOP mode, if necessary.
Example of user safety function and fault reaction function
In the event of overpressure, the F-system will open a valve (user safety function). For a
hazardous F-PLC fault, all outputs are shutdown (fault response function); the overpressure
valve opens, and also the other actuators go into a safe state. For a non-faulty F-system, only
the valve would be opened.
Safety Integrated (with SINAMICS S120)
Commissioning Manual, 02/2020, A5E46305916B AB
53
