Mobatime 122031, Mounting And Instruction Manual

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8.14 Redundant operation of 2 DTS 4160.grandmaster
For redundant operation two DTS 4160 devices are
synchronized via optical fibres. For this purpose, a mini GBIC
module is plugged into both devices and connected via
optical fibres (see Appendix H Technical data):
mini GBIC module
In this scenario both devices have a GPS receiver (GNSS source priority 1). Both
devices are configured for the redundant mode (red. link source priority 2), but are
basically equal and work out the master/slave role among themselves. The slave
supervises the system time on the basis of its own GPS time and generates an error
message, should the time difference amount exceed the configurable value of n
nanoseconds.
•
Starting the devices with fibre optic connection
The devices work out among themselves which is the master (normally the one
synchronized first)
•
Both devices are always synchronized from GPS
Both devices show the same stratum level (usually stratum 1).
The fibre optic connection is only used for status exchange and time compare.
•
In case of loss of the master GPS, the master checks if the slave is better
synchronized. If the slave is better synchronized the slave takes over the master
role (only in case it is still synchronized to its own GPS). The previous master
becomes the slave and is synchronized via optical link from master. At this point the
stratum of the slave is: master s1.
•
In case of loss of the slave GPS, the slave is synchronized via optical link from
master. Stratum is increased to master s1.
•
In the case of a loss of the master (power down), the slave assumes the master
function.