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8.10 Redundant operation of 2 DTS 4132.timeservers
For redundant operation two DTS 4132 devices are synchronized via optical fibers. For
this purpose, a mini GBIC module is plugged into both devices and connected via
optical fibers (see Appendix H Technical data):
mini GBIC module
Both devices have a GPS receiver in redundant operation or external timeservers as
time source. Both devices are configured for the redundant mode, but are basically
equal and work out the master/slave role among themselves. The slave is always
synchronized to the master in operation. The slave supervises the system time on the
basis of its own GPS time (or external timeserver time) and generates an error
message, should the time difference amount exceed the configurable value of n
milliseconds.
•
Starting the devices with fiber optic connection
The devices work out among themselves which is the master (normally the one
synchronized first)
•
Starting the devices without fiber optic connection
The devices do not send out any time information until there is an optical fiber
connection, or the devices are reconfigured.
•
The slave synchronizes to the master.
Whereby stratum/slave = stratum/1
The time of the slave is always set immediately to the master time (no fine
adjustment).
DTS Master
DTS Slave
LWL connection (DTS Link)
(option for redundant
operation)
status, time
NTP
NTP
Ethernet
GPS
receiver
GPS
receiver
status, time
