Siemens SIMATIC PCS 7 CPU 410-5H System Manual page 203

OB 82
In redundant mode, the operating system of the CPU calls OB82 in case of a Snyc link fault.
You can display the following channel-specific diagnostic data in the Module state tab dialog
for the selected synchronization module:
● Overtemperature
The synchronization module is too hot.
● Fiber-optic error
The sender of the electro-optical component has reached the end of its service life.
● Violation of lower limit
The sent or received optical performance is low or too low.
● Violation of upper limit
The sent or received optical performance is high or too high.
● Functional error of the network component
The quality of the redundancy link between the CPUs (transmission distance including
synchronization modules and fiber-optic cables) is reduced so that transmission errors
are occurring frequently.
In redundant mode the OB82 is also called at Power Off/On or at a firmware update of the
partner CPU. This does not indicate any problem with the synchronization link but is instead
due to the fact that the synchronization modules are not emitting any light at this moment.
Fiber-optic interfaces of unused modules
Fiber-optic interfaces of unused modules must be blanked off during storage to protect the
optical equipment. The plugs are in the synchronization module when shipped.
NOTICE
Reduced optical performance due to dirt
Even small amounts of dirt in a fiber-optic interface adversely affect the quality of the signal
transmission. This can lead to synchronization losses during operation.
Protect the fiber-optic interfaces against dirt during storage and installation of the
synchronization modules.
CPU 410-5H Process Automation
System Manual, 09/2014, A5E31622160-AB
12.1 Synchronization modules for the CPU 410-5H
Synchronization modules
203