Mtm Alarm System Circuits; Alarm Cross-Connect Unit Panel; Alarm Control And Display Panel - Nortel DMS-100 Series Reference Manual

MTM alarm system circuits

In the Version 2 OAS, the OAU must contain an OAU dead system card
(NT3X82). The SC and SD points that generate the OAU and dead system
(DS) alarms are in the NT3X82. This card must be the same type as the
equivalent card in the standby MTM or ISM. That is, the two cards must
both be the common audible or the unique audible type. When you install
unique audible type, the NT3X82 card in the standby MTM or ISM provides
the following:
backup for the 20-Hz ringing generator
hybrid transformer for the 'even' aisle multiple of the local talk line
circuit
control relays which complete the circuits of the dead system alarm
To perform the OAU backup functions, the standby MTM or ISM receives
power from a different power distribution center (PDC) and battery feed
(A/B supply) than the OAU. You assign the standby MTM to a different
network module.

Alarm cross-connect unit panel

In the Version 2 OAS, the alarm cross-connect unit (AXU) panel
(NT3X89AA, NT3X89BA) replaces the alarm crosspoint field shelf
(NT0X62). The AXU shelf is in the top provisionable shelf position directly
above the OAU shelf. The AXU shelf is functionally similar to the Version
1 shelf. The AXU shelf uses connectorized cables for every equipment
interconnection except for interconnections to the audible alarm panels. A
screw-connect terminal strip makes these interconnections. The AXU panel
contains data link control cards (NT0X89). Chapter 6 covers data link
control cards
The NT3X89BA AXU is a version for –60V applications. The NT3X89BA
does not support the data loop control (DLC) function.
In some applications, Version 2 alarm equipment interconnects through the
DF without the use of an AXU shelf. Figure 4-1 shows his configuration.
Figure 4-2 shows the equipment interconnections for a large office alarm
system. These interconnections use the Version 2 OAS components and an
AXU shelf.

Alarm control and display panel

The alarm control and display (ACD) panel (NT0X63AA) is an important
component of the OAS. Figure 3-1 shows this panel. The alarm control and
display panel is physically separated from the OAU and located at the MAP
terminal for operational support. The ACD has lamps that display the type
DMS-100 Family Alarm System Description Reference Manual BASE12
Office Alarm System Version 2 3-3