Siemens Simatic S7-1500 - Configuration of a Fail-Safe System with SIMATIC S7-1500 HF

System overview
5.2 Configuration
S7-1500R/H redundant system
System Manual, 01/2024, A5E41814787-AF
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5.2.3 Configuration of a fail-safe system with SIMATIC S7-1500HF
Configuration
Fail-safe automation systems (F-systems) are used in systems with higher safety
requirements. F-systems control processes and ensure that they are in a safe state
immediately after shutdown. In other words, F-systems control processes in which an
immediate shutdown does not endanger persons or the environment. The 1518HF-4 PN CPU
is a high-availability H-CPU with integrated F-functionality (HF-CPU).
The HF system is made up of the following components:
• 2 HF-CPUs
• 2 SIMATIC Memory Cards
• 4 synchronization modules (two synchronization modules in each HF-CPU)
• 2 redundancy connections (two duplex fiber-optic cables)
• IO devices with fail-safe modules
• optional load current supply
• optional system power supply (only via active backplane bus)
You can combine fail-safe I/O modules and non-fail-safe I/O modules in the IO devices.
The HF system (with the 1518HF-4 PN CPUs) exchanges:
• Safety-relevant data with fail-safe modules of the IO devices
• Non-safety-relevant data with non-fail-safe modules of the IO devices