Fault-Tolerant Automation Systems; Redundant Automation Systems In The Simatic Series; Figure 2-1 Operating Objectives Of Redundant Automation Systems - Siemens SIMATIC S7-400H System Manual

Fault-tolerant automation systems

2.1

Redundant automation systems in the SIMATIC series

Operating objectives of redundant automation systems
Redundant automation systems are used in practice with the aim of achieving a higher
degree of availability or fault tolerance.
Figure 2-1
Note the difference between fault-tolerant and fail-safe systems.An S7-400H is a fault-tolerant
automation system that may only be used to control safety-relevant processes in conjunction
with additional measures.
Why fault-tolerant automation systems?
The purpose of using fault-tolerant automation systems is to reduce production downtimes,
regardless of whether the failures are caused by an error/fault or are due to maintenance
work.
The higher the costs of downtimes, the greater the need to use a fault-tolerant system.
The generally higher investment costs of fault-tolerant systems are soon returned by the
avoiding loss of production.
S7-400H
System Manual, 09/2007, A5E00267695-03
Operating objectives of redundant automation systems
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