Types Of Alarm/Bits Modules - Nortel 15000 Hardware Description

The suspension of timing depends on how the timing was configured in the
software. Since the software detects and reports a missing card, which is
triggered as soon as the cable to a card is disconnected, your replacement
activity must be coordinated with the software operator of the node to ensure
minimum impact on service. Have the software operator consider putting the
CP timing in holdover mode or line timing for the duration of the replacement.
There are no software or hardware alarms specific to the removal of the
alarm/BITS module itself or leaving its slot empty. Other alarms that may occur
as a result of the removal of the alarm/BITS module are described in
Hardware alarm definitions and behaviors (page
When the module is replaced, reporting of current alarm status resumes.
Unlike most other hardware parts in a Multiservice Switch 15000 or
Multiservice Switch 20000, there is no software command associated with
locking, removing, inserting, or unlocking the alarm/BITS module, however
there are commands for locking the ports on the module.
The alarm/BITS module passes the signals over the shelf backplane to the
control processor (CP) cards and expansion slots. (The expansion slots are
currently unsupported.)
The alarm/BITS module is a field-replaceable unit (FRU).
This section provides the following information about the alarm/BITS module:
• Types of alarm/BITS modules (page 94)
• Alarm/BITS module faceplate (page 95)
• Alarm/BITS module cable assemblies (page 100)
• Timing cable specifications for the DS1 circuit (page 101)
• Timing cable specifications for the E1 balanced circuit (page 101)
• Timing cable specifications for the E1 unbalanced circuit (page 102)
• Line build out application settings (page 103)

Types of alarm/BITS modules

The types of alarm/BITS module are matched to the CP cards for the type of
interfacing signal as follows.
The types of the alarm/BITS module for a Multiservice Switch 15000 include
• NTHR12, for balanced DS1 twisted pair (matched to the DS1 CP NTHR06
or NTHW06)
• NTHW76, also for the DS1 CP types NTHR06 or NTHW06. This module
is intended for use with the external sync wire-wrap cable assembly
Copyright © 2005, Nortel Networks
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Shelf assembly
Nortel Networks Multiservice Switch 15000/20000
Hardware Description
NN10600-120 sPCR6.1S1 Standard
sPCR6.1 February 2005
48).
Nortel Networks Confidential