Orolia SecureSync 2400 User Manual

For more information on the TFOM value and Phase Error Limit, see "Configuring
the Oscillator" on page230.
Note: Changes made to the Holdover Timeout always take effect imme-
diately. If SecureSync is in Holdover and the Holdover timeout is changed to
a value that is less than the current time period that SecureSync has been
in Holdover Mode, the unit will immediately declare loss of synchronization.
What is the recommended setting for the Holdover Timeout period?
The factory default Holdover period is 2 hours (7200 seconds) . The value can be
increased to up to 5 years. During this time period, SecureSync will be useable by its NTP
clients (or other consumers) after GNSS reception has been lost.
The length of time is really based on the type of oscillator installed in a unit, and what the
typical accuracy requirements are for the NTP clients. The longer it can run in Holdover
mode before it expires, the longer it can continue being a central time source for all of its cli-
ents. But the longer SecureSync runs in Holdover, the larger the offset to true UTC time
will become, because the undisciplined oscillator will drift over time:
The better the type of oscillator installed, the more stable it is while in Holdover and there-
fore, the less its time will drift away from true UTC time. This results in more accurate tim-
ing, over extended durations upon the loss of GPS input. For instance, a Rubidium
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CHAPTER 3 • SecureSync 2400 User Manual Rev. 2
3.4 Holdover Mode

Orolia SecureSync 2400 Specifications

General

Brand	Orolia
Model	SecureSync 2400
Category	Recording Equipment
Language	English