External Alarms Panels; Alarms; Office Alarm Unit - Nortel DMS-100 Series Reference Manual

2-6 Office Alarm System Version 1
The alarm crosspoint field shelf (NT0X62AA) is in the top shelf position of
the frame that contains the OAU shelf. The alarm crosspoint field contains
vertical mounting plates. Forty-five connectors, a 200-pin terminal strip,
and four data link control cards (NT0X89) are mounted. A front cover
protects all of these components.
The alarm crosspoint field connects to the OAU through a wiring harness.
The harness is in 11 connector plugs at the back of the OAU. At the
crosspoint field, this harness connects to the appropriate connectors and to
pins on the 200-pin terminal strip. Cable-to-terminal blocks on the DF
connect to the terminal strip.
Alarm systems that require increased alarm detection capability use the
crosspoint field shelf extension (NT0X62AB).
Connections to the other parts of the alarm system can be through
connectorized cables plugged into the connectors on the crosspoint field.
These connections can be through cables wired to pins at the rear of the
connectors. These onnections can also be through the DF and the terminal
strip. Interconnections are also made at the rear of the crosspoint field
between connectors, the terminal strip, and the data link control cards. The
data link control cards provide control relays for the office data loop system.

External alarms panels

For information on external alarms panels, see Chapter 4.

Alarms

Office alarm unit

In the Version 1 OAS, the alarm circuits are in the alarm circuit #3
(NT2X43) card. This card is on OAU and standby MTM shelves. Two scan
points, ABOAUFL and ABMTMFL, on separate scan detector (NT0X10)
cards, interact with the NT2X43 card to provide a route to CC to identify
OAS system failures. The ABOAUFL scan point in the OAU shelf monitors
the NT2X43 card in the standby MTM. The ABMTMFL scan point in the
standby MTM monitors the NT2X43 card in the OAU shelf. The OAS
generates an ABOAUFL or ABMTMFL alarm at the MAP terminal if the
OAU or standby MTM shelf loses any of the following:
297–1001–122 Standard 06.01 August 1999
–48V battery supply
130V dc supply for the remote alarm transfer circuit
130V ac, 20-Hz ringing supply for audible alarms
communication with CC