Nortel Networks NN43001-301 - Manual (Page 168)

168 Clock Controller description and installation
Free run (non-tracking) mode
The clock synchronization for a PRI loop can operate in free-run mode if:
• the loop is not defined as the primary or secondary clock reference
• the primary and secondary references are disabled
• the primary and secondary references are in a local alarm state
Small System Clock Controller daughterboard
The Small System supports a single onboard clock controller daughterboard,
the NTAK20, located on either:
• the NTRB21 1.5 Mbyte DTI/PRI card
• the NTAK09 1.5 DTI/PRI card
• the NTAK10 2 Mbyte DTI card
• the NTAK79 2 Mbyte PRI card
• the NTBK50 2 Mbyte PRI card
The clock controller circuitry synchronizes to an external reference clock and
generates and distributes the clock to the system. This enables the system
to function either as a slave to an external clock or as a clocking master.
Note: When configuring ISL over analog trunks, clock controllers are
not required.
Installation procedures
This section provides procedures on how to install a clock controller on
Large Systems.
CAUTION
Do not deviate from the procedures described in this section. Call
processing can stop if procedural steps are not followed properly.
Determine slots and shelves
Table 64 "Clock Controller shelves and slots" (page 169) shows the systems,
the shelves and available slots.
Nortel Communication Server 1000
ISDN Primary Rate Interface Installation and Commissioning
NN43001-301 02.03 Standard
Release 5.5 7 December 2007
Copyright © 2003-2007, Nortel Networks
.