Redundancy in PLCnext Technology
In engineering, redundant systems are key for enhancing operational reliability: Critical components are intentionally duplicated (in safety-critical systems: triplicated) to provide a permanent backup or fail-safe to take over operations immediately in case the main component fails.
In PLCnext Technology, redundancy is implemented in two ways:
- System redundancy by means of two specialized high-performance PLCnext Control devices:
RFC 4072R with firmware release 2022.0 LTS is developed especially for the purpose of working as a redundancy tandem. - Applicative System Redundancy (ASR) by means of the PROFINET system redundancy:
The PROFINET standard describes several types of system redundancy. PLCnext Control supports PROFINET system redundancy type S2 according to that PROFINET specification. Of course, you'll have to run a PROFINET station in order to use this mechanism.
In a use case of the Belgian tunnel authorities both methods were evaluated, and system redundancy was the path to follow for that case. Now a set of pairs of RFC 4072Rs is working smoothly in traffic tunnels of Brussels.
- Introduction to ASR
- PLCnext Engineer for redundant systems
- Function block for Controller Redundancy
- Function blocks for Data Synchronization
- Function block for gathering port states from bus couplers
- Function block for gathering SNMP values from managed switches
- System redundancy with RFC 4072R
- IP addresses at redundant controllers
- Configuring redundant PROFINET devices
- Redundancy error codes
- System variables - Redundancy
• Published/reviewed: 2024-12-10 ☃ Revision 075 •