SERTEL T-GPS-300, Operation Manual

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28.
Redundant Comparator Unit
This Unit consists of 2 identical Redundant Comparator Modules connected to the
outputs of GPS RECEIVER & Master Clocks A & B. The Redundant Units receive the
time signals generated by the Master Clocks A & B Compares them to assess
synchronization. If the time data of both clocks agree, the Redundant Comparator
“A” generates the required outputs and Redundant Unit “B” Through fully Operate is
Kept as Standby in case of mismatch. This status is indicated in the panel , Full
redundancy is obtained as shown below.
01 . In case of non availability of Satellite signal; the built in oscillator of GPS receiver is
used as time reference to update the GPS time system and give necessary time
outputs to Master Clock.
02. In case of failure of any one Master Clock; the signal are automatically generated
by the redundant clock.
03. In case of non functioning of both Master Clocks, the signals are fed directly from
the GPS Receiver of the Redundant Unit. This provision is normally not required.
Only in emergent case, this has to be activated by a manual switch available on
the front panel.
04 T he Redundant Comparator Units generate the following outputs:
a) Differential Pulse outputs to drive Slave Clocks.
c) Alarm contacts to provide status alarm.
d) RS 232 (BHEL DDC Format)
e) Pulse Output
f) IRIG B (AM) output.