SERTEL T-GPS-300, Руководство по эксплуатации

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21. GPS / MASTER CLOCK & SLAVE CLOCK SYSTEM
.01 . GPS Antenna
Collects the signals transmitted by GPS satellites and transmit the data to the GPS
Receiver for further processing through the low loss inter connecting cable.
02 . GPS Receiver A & B
Collects the signals from the GPS Antenna and generates 1 No of RS 232 and
Pulse output (1 PPS) to synchronise the Master Clock.
03 Master Clock A & B
These are 2 Nos of separate highly stable electronic clock system with in built high
stable Oven Controlled Crystal Oscillators as time reference. The Master Clocks are
constantly monitored by the outputs signals of the GPS receiver to keep them in
synchronism with the GPS Receiver / time.
The OCXOs used as time reference in these clocks are quite stable with an
accuracy better than 1 PPM These clocks generate necessary time signals and feed
them to Redundant Comparator Units A & B for further processing. An alarm contact
to indicate the non-availability of synchronizing signals from the GPS unit is included
in the clock system to provide visual indication of the failure status
04 Redundant Comparator Unit
Redundant comparator:
This unit receives the time signal generated by Master Clock A and Master
Clock B. The comparator compares the received signals and gives the healthy signal as output.
If any one master fails automatically it accepts the signal from other master clock without any
time delay and gives output. The output of this comparator unit is connected to the respective
signal conditioners.
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The MASTER CLOCK Redundant Comparator Units generate the following
outputs:
1. Differential Pulse outputs to drive Slave Clocks.
2. Alarm contacts to provide status alarm.
3. RS 232 Output (DDC format)
4. Pulse Output
5. IRIG B (AM) output.
6 . TCP IP Output
7. TCP ON NTP Output