Alarm/Bits Module - Nortel Passport 15000 Hardware Description

114 Chapter 3 Shelf assembly

Alarm/BITS module

241-1501-200 5.2S2
The alarm/BITS module provides the alarm monitoring and the building
integrated timing supply (BITS). There is only one alarm/BITS module per
Passport 15000 or 20000. When it is removed or failed there is no:
• BITS timing signal to the control processors (CPs)
• reporting of the fabric LED status to the software
• reporting of any cooling unit alarms to the control processors (CPs)
• reporting of any CP alarms to the breaker interface panel (BIP)
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 or module is disconnected, your
replacement activity must be coordinated with the software operator of the
switch 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:
• 7002 0003, if the fabric card component temperature has increased above
the accepted operating temperature
• 7012 0051, if the cooling unit is not function correctly on a bus-based
shelf or the cooling fan is not functioning correctly or the temperature is
too high on a fabric-based shelf
• 7017 1000, if the CP is not synchronized to the reference
When the module is replaced, reporting of current alarm status resumes.
Unlike most other hardware parts of the Passport 15000 or 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.