Spectracom SecureSync User Reference Manual page 169

3.
Example 5—Time at Power-Up ("Local System Time") to be Considered "Valid".
GNSS Input to serve as 1PPS Reference
The objective of this use case is to use the time that SecureSync uses as it powers up (without the
need for a user to manually set it, as would be the case with a "User" selected time). This is
referred to as "Local System" time.
Since "Local System" cannot be both Time , and 1PPS input together, in this use case example the
GNSS input will be set as the 1PPS reference (other use cases may require using different ref-
erences, e.g. IRIG.)
As there is no default entry for "Local System" and "GPS", a new entry needs to be added to the
Reference Priorities table in order to use this combination of references.
Step-by-step procedure:
1.
2.
3.
3.6.5.4 Configuring Input Reference Priorities
SecureSync can use numerous external time sources, referred to as "references". As external
time sources may be subject to different degrees of accuracy and reliability, the user can determ-
ine in which order (= priority) SecureSync calls upon its external time and 1PPS references.
For additional information, see "Input Reference Priorities" on page 148.
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3 SecureSync User Reference Guide Rev. 18
The time can be manually set through the System Time panel located in the
MANAGEMENT/OTHER/Time Management page. See "Editing the System Time" on
page 169 for details on setting the time manually. Once you have set the date and time, the
front panel sync light will turn green.
NOTE – This procedure needs to be repeated each time SecureSync is power-
cycled (with no other references available,) unless synchronizing to a battery backed
time on startup is enabled, or after each time all higher priority references are lost.
Add a reference to the Reference Priority by clicking the PLUS icon. Use the following set-
tings, then click Submit :
In the Priority Level text box, enter 1 . This will give this reference the highest pri-
ority.
In the Time field, select "Local System"
In the PPS field, select "GPS".
Check the Enabled checkbox.
Confirm that the first reference in the Reference Priority table has "Local System" as the
Time input and "GNSS" as the 1PPS input.
After a power cycle or reboot, as soon as GNSS is declared valid, the System Time will
automatically be used as-is, with no manual intervention required.
3.6 OTHER Setup Pages
153