AT&T MERLIN LEGEND Communications System PBX System Planning Manual page 78

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Planning Form Instructions - Continued
Under "Priority" in the "Clock Synchronization" section of Form 3c:
9 . If installing only one 100D module:
Check "Primary" to keep the factory setting. (this module provides
synchronization for the system.)
Check "None" if the synchronization source is other than through the
100D module.
Continue to Step 11.
10. If installing more than one 100 D module, decide which module, if any,
provide the primary synchronization.
If Module 1 provides clock synchronization, check "Primary" in the first
column (the factory setting).
If Module 2 (or Module 3) provides clock synchronization, check
"Primary" in the column that describes that 100D module.
If the synchronization source is other than through a 100D module,
check "None.
If assigning backup sychronization:
Check "Secondary" in the column that describes the 100D module
providing secondary synchronization.
Check "Tertiary" in the column that describes the 100D module
providing tertiary backup.
11. Under the "Source" subheading in each column:
Check "Loop" to retain the factory setting. The system uses the clock
of the far-end connection.
Check "Local" to change the setting (The clock is free-running.)
12. Under the "Activation" subheading in each column:
Check "Active" if loop clock synchronization is taking place.
Check "Not Active" if the clock is free-running.
NOTE: Normally, the primary synchronization source is et to "active"
and other modules are set to "not active."
Trunk Options 3-23