Spectracom VersaSync - Page 133

Note: The Battery Backed Time is also referred to as the time maintained 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 references) and
the hand-set time entered manually during commissioning of the system is suf-
ficiently accurate
the system needs to be able to completely recover from a temporary power loss,
or similar, without human intervention.
c.
A system is used for simulation or testing purposes, and UTC traceability is not required.
The Accuracy of the Battery Backed Time …
… depends on the accuracy of the hand-set time if the time is set manually in an autonomous
system. In a non-autonomous system (i.e, when using external reference(s)) VersaSync's System
Clock will regularly update the battery-backed time.
Another factor impacting the accuracy of the battery-backed time is how long a VersaSync unit
is powered off: Any significant amount of time will cause the battery-backed RTC to drift, i.e.
the battery-backed time will become increasingly inaccurate.
The battery used for the RTC is recharged during operation of the unit, and is designed to last
for the lifetime of the product.
Distributing battery-backed time over NTP
When distributing a hand-set, battery backed time via NTP, please set the time relatively close
to UTC, so as to prevent NTP synchronization problems when transitioning from the hand-set
time to a UTC- based external input reference. See also "Input Reference Priorities" on
page129.
To use the battery-backed time as the synchronized time at start-up:
1.
Navigate to MANAGEMENT > OTHER: Time Management.
2.
In the System Time panel click the GEAR icon.
3.2 System Time
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