Spectracom NetClock 9400 Series, Руководство пользователя

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c.
To utilize a backup reference as soon as possible after a power cycle or reboot of NetC
lock, while waiting for the primary reference (e.g., GNSS) to become valid. To this end,
in the
Edit System Time window, the checkbox Synchronize to Battery Backed Time on
Startup must be checked, AND the User/User reference is assigned a reference priority
number other than "1". Note that a Time jump and/or 1PPS jump are likely to happen
once the primary reference becomes valid.
Combining a User Time reference with a non-User 1PPS reference or vice versa is not a typical
use case. Use the
Local System
reference instead, see "The "Local System" Reference" on
page 166.
Built-in safety barrier
In order to "validate" (=
green
status lights) the User/User reference, the hand-set time must be
manually submitted every time after NetClock reboots or resets, or after the Holdover period
has expired: In the
Edit System Time window, the checkbox Manual Time Set must be checked.
The System Time displayed in the field below will become valid the moment the Submit button is
clicked.
See also below, " How long will the User/User reference be valid? ": The notion of limiting the
validity of the User/User reference also serves as a safety feature.
How long will the User/User reference be valid?
Since the User/User reference does not qualify as a legitimate, traceable time, it becomes
invalid once NetClock is reset, or power-cycles, or after the Holdover Time expires (whichever
occurs first). It then needs to be set manually and submitted again (
Edit System Time > Manual
Time Set ).
The only workaround for this is "Using Battery Backed Time on Startup" on page 152. This will
allow NetClock to apply the
User/User reference after a power-cycle without manual inter
vention.
How to setup the User/User Reference
168
CHAPTER
3
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NetClock User Reference Guide Rev. 16
3.3 Managing Input References