EndRun Meridian II, Руководство пользователя

Страница: 205 / 240

M e r i d i a n I I U s e r M a n u a l 185
"Smarter Timing Solutions"
Appendix
G
System Faults
The status of the Meridian II is constantly monitored and a fault will occur when any of several
parameters is out of spec. When this happens the Alarm LED on the front panel will light. This ap-
pendix defines the various faults.
Overview
The Alarm LED will light when a fault has occurred. You can see which fault is the problem by us-
ing the
faultstat
command.
Masking Faults
Some faults can be masked. These are the ANT (GPS Antenna) and SIG (GPS Signal) faults. When
masked, these faults will not cause an alarm. You may want to mask the ANT fault if you are using a
GPS splitter. You may want to mask the SIG fault if you are operating your Meridian II as a Stratum
2 NTP Server and are not using a GPS signal. For information on Stratum 2 see
Chapter 7 - NTP,
Configuring the Meridian II as a Stratum 2 Server .
To mask a fault you can use the front-panel keypad/display or a console port commands
setantflt-
mask
and
setsigfltmask
. For more information see
Chapter 3 - Console Port Control and Status
or type
help setsigfltmask
and
help setantfltmask
on the console.
If your Meridian II has the Dual Power Supply option then you may mask primary and/or secondary
power supply faults. See
Chapter 10 - Options, Masking Dual Power Supply Fault Alarms
for more
information.
System Fault Definitions
System Oscillator DAC (DAC)
This fault indicates that the electronic frequency control DAC for the oscillator has reached either the
high or low alarm limit while locked to the GPS signal. Unless the unit is being subjected to out-of-
specification environmental conditions, this would indicate that the oscillator frequency has drifted
near to the end of life region. This should normally only occur after at least ten years of operation.
The unit will continue to function until the oscillator frequency finally reaches one of the actual DAC
endpoints. The unit should be returned to the factory for oscillator replacement at your convenience.
GPS Signal (SIG)
This fault indicates that the unit has not been able to acquire a GPS signal for one hour while the
Time Figure of Merit has been 9, the unsynchronized condition. This could be due to a variety of
reasons. If there are no other faults that could explain the inability to receive a signal, then there
could be an antenna failure or blockage. If the condition persists indefinitely, and a problem with the
antenna is not evident, then please contact EndRun Customer Support.