Siemens CPU 412-5H Equipment Manual page 23

Points to observe when installing the fiber-optic cables for the S7-400H synchronization link
Always route the two fiber-optic cables separately. This increases availability and protects the
fiber-optic cables from potential double errors caused, for example, by interrupting both cables
at the same time.
Always make sure the fiber-optic cables are connected to both CPUs before switching on the
power supply or the system, otherwise the CPUs may process the user program as the master
CPU.
If you are using fiber-optic cables that were not stored with dummy plugs on the connectors,
observe the following:
Clean connectors, particularly the optical surfaces, with a soft, clean and lint-free cloth before
use.
Local quality assurance
Check the points outlined below before you install the fiber-optic cables:
● Does the delivered package contain the correct fiber-optic cables?
● Any visible transport damage to the product?
● Have you organized a suitable intermediate on-site storage for the fiber-optic cables?
● Does the category of the cables match the connecting components?
Check the attenuation of the fiber-optic cables after installation.
Storage of the fiber-optic cables
if you do not install the fiber-optic cable immediately after you received the package, it is
advisable to store it in a dry location where it is protected from mechanical and thermal
influences. Observe the permitted storage temperatures specified in the data sheet of the fiber-
optic cable. You should not remove the fiber-optic cables from the original packaging until you
are going to install them.
NOTICE
Failure of data traffic due to dirty optical plug connectors
Optical sockets and connectors are sensitive to dirt on the front surface. Dirt can lead to failure
of the optical transmission network. Make the following precautions to avoid the function being
impaired:
● Clean the front surface of field-assembled connectors carefully before insertion. There can
● Only remove the dust covers from optical synchronization modules and pre-assembled
● Seal unused optical sockets, connectors and synchronization modules with the supplied
Synchronization modules for S7-400H
Equipment Manual, 04/2020, A5E50072434-AA
be no residue of the work process remaining on the connector.
cables shortly before inserting the cables.
protective caps.
5.6 Installation of fiber-optic cables
Assembling
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