TFS NTP80plus, Справочное руководство

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MANUAL P/N 900000165 REV H
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The following lists all the events and their causes that can appear in the event log. They will
cause an SNMP v1 trap to be sent to SNMP enabled ports. GPS events are also shown on the
front panel of the NTP80, and these events will be shown in the relevant status field on the web
status page.
The events are divided into three sections. SYSTEM, GPS and NTP.
SYSTEM
System startup. Initialisation of event log. Not visible after first 800 events.
Manual restart Remote reboot has been applied.
GPS
Normal GPS operating normally.
No PPS - in holdover GPS not tracking – NTP80 in holdover.
PDOP too high Tracked satellite constellation too poor for good position
resolution. NTP80 in holdover.
Only 3 usable sats
Only 2 usable sats Satellites tracked, requires at least 4 for time to load
Only 1 usable sat initially.
No useable sats
No time yet GPS start up.
Antenna shorted There is a fault with the antenna connection.
No antenna present No antenna is connected. Check antenna is connected.
Not detected Initial start-up condition.
All the above are decoded from the status value visible on the web page and relate to the GPS
operating status. If all is well then the last event will be Normal. Any single event will be cleared
by returning to Normal - so if the antenna is disconnected then the minimum event sequence
will be 'No antenna present' and then after reconnection 'Normal'. In reality some intermediate
messages will occur as the number of satellites tracked increases. In most cases, if any state
other than normal is seen persistently then the likelihood is that there is an issue with the GPS
reception either due to antenna placement, operation or cable length.