Spectracom VelaSync 1225, Руководство пользователя

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iii.
In the Oscillator Settings window, set the Holdover Timeout .)
9.
Check on the HOME screen that User 0 is displayed, with a green STATUS. Note
that the Disciplining State will remain yellow , once Holdover has expired, since
the system time is not synchronized to a reference.
Note: Contrary to the User reference discussed above, the Local Sys-
tem reference can be used for Time, or 1PPS (but not both). For more
information, see "The "Local System" Reference" on page 115 .
3.2.1.4 Using Battery Backed Time on Startup
Upon system startup, by default VelaSync will not declare synchronization until one of
the external references becomes available and valid.
This functionality can be overridden by enabling the Synchronize to Battery Backed
Time on Startup , thus allowing the battery backed time to be used as System Time
upon system startup. The Battery Backed Time is also referred to as the time main-
tained by the integrated
Real Time Clock ( RTC )
This will result in VelaSync providing a System Time before one of the external ref-
erences becomes available and valid. This will happen automatically, i.e. without user
intervention. As soon an external reference will become available, its time will take pre-
cedence over the battery backed time: The System Clock will adjust the System Time
for any time difference.
Note: The Battery Backed Time is also referred to as the time main-
tained by the integrated Real-Time Clock (RTC).
Use Cases
Using the Battery Backed Time on Startup is typically used in these cases:
a.
If the synchronization state is to be reached as quickly as possible, even if this
means the time distributed initially will most likely be less accurate than an
external time reference.
b.
A system is intended to operate autonomously (i.e. without any external ref-
erences) and
the hand-set time entered manually during commissioning of the system is
sufficiently accurate
3.2 System Time
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