Nortel Networks Circuit Card 311 - Manual (Page 223)

Clocking Requirement 223
goes out. The LED goes out if either the motherboard or daughterboard is
enabled by the software. If the LED flashes continuously or remains weakly
lit, replace the card.
Clocking Requirement
The clocking for NT5D14 Lineside T1 Interface card in CS1000 Rls 5.0
system is as follows:
• Lineside T1 cards are clock master of their T1 link, which has a clock
accuracy requirement of +/-50ppm
• MGC does not provide a backplane clock with +/-50ppm accuracy at
freerun
• An accurate clock source is needed for Lineside T1 application
The following are the two methods to bring an accurate clock source to MCG:
• Configure a digital trunk card with Clock Controller within the same
cabinet/chassis as Lineside T1 cards.
With Clock Controller enabled, in both freerun or locked state, an
accurate clock will be provided to MGC.
• Use an MGC DECT Clock Reference Cable (NTDW67AAE5) to bring
a clock source from other CS1000 cabinet/chassis that has a Central
Office Link.
With accurate clock source available, MGC will lock to the reference and
provide an backplane clock as accurate as the clock source.
Connecting MGC DECT Clock Reference Cable
The following sections elaborate on how to connect an MGC DECT Clock
Reference Cable.
Pre requisites
The pre requisites for connecting an MGC DECT Clock Reference Cable
are the following:
• MGC DECT Clock Reference Cable --- NTDW67AAE5.
Figure 39 "MGC DECT Clock Reference Cable" (page 224) shows the
MGC DECT Clock Reference Cable. It is used to provide clock reference
between CS1000 Media Gateway Cabinet/chassis.
Nortel Communication Server 1000
Circuit Card Reference
NN43001-311 01.04 Standard
Release 5.0 23 May 2008
Copyright © 2003-2008, Nortel Networks
.