Orolia Spectracom VelaSync 1232, User Manual

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(whichever occurs first). It then needs to be set manually and submitted again ( Edit Sys-
tem Time > Manual Time Set ).
The only workaround for this is "Using Battery Backed Time on Startup" on page 101 .
This will allow VelaSync to apply the User/User reference after a power-cycle without
manual intervention.
How to setup the User/User Reference
See "Manually Setting the Time" on page 99 .
Using the "User" Reference with Other References
If the User/User reference is used in conjunction with other, external references (such as
GNSS or IRIG), the System Time should be set as accurately as possible:
Otherwise, the large time correction that needs to be bridged when switching from a lost
reference to a valid reference, or from a valid reference to a higher-priority reference that
has become available again, will cause NTP to exit synchronization. If the difference is
under 1 second, NTP will remain in sync and will "slew" (over a period of time) to the new
reference time.
3.3.1.4 Reference Priorities: EXAMPLES
Example 1 – GNSS as primary reference, IRIG as backup:
In this use case, the objective is to use:
GNSS as the primary Time, and 1PPS reference
IRIG as the backup Time, and 1PPS reference.
Step-by-step procedure:
1.
Move the reference which has “GPS 0” in the Time column and “GPS 0” in the
1PPS column to the top of the table, with a Priority value of 1. Click the Enabled
checkbox.
2.
Move the reference which has “GPS 0” in the Time column and “GPS 0” in the
1PPS column to the top of the table, with a Priority value of 1. Click the Enabled
checkbox.
3. Move the reference which has “GPS 0” in the Time column and “GPS 0” in the
1PPS column to the top of the table, with a Priority value of 1. Click the Enabled
checkbox.
Since both of these references are
default
references, no additional references need to be
added to the Reference Priority table.
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VelaSync 1232 User Manual Rev. 4
3.3 Managing References