6.1.2 Replacement of bus components in runtime
Introduction
The information in this section relates to the following bus components
● Bus cable
● Bus links
● Switches, bridges
Failure and replacement of bus components
Components of a bus system (plant bus, terminal bus, fieldbus) can be replaced when there
is no risk of accidentally affecting other components as a result of the replacement.
Before making a replacement, the following aspects must be taken into consideration:
● Bus topology (for example ring structure, spur lines, redundancy connections, disrupted
bus cable)
● Connection of the bus system to "master systems":
– The assignment of clients to servers
– The connection to time master systems
– The connection to domain controllers
– For PCS 7 OS: The setting of preferred servers
● Other disrupted components
Recommended procedure
If a bus component is partially functional, we recommend the following procedure:
● If repairs are necessary, first replace the defective bus cable.
● Insert a new bus component into the existing system before you remove the old bus
component completely.
● Avoid the occurrence of double faults.
● Replace the connection to the connected components in series (not at the same time).
Replacing components and plant changes
6.1 Failure and replacement of components
High Availability Process Control Systems (V9.0)
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