Nortel DMS-100 Series Maintenance Manual page 52

1-36 Maintenance overview
The multi-output power converter, that occupies slots 17 and 18 of the
RMM, provides a regulated, common-ground dc power supply. This power
supply has five different outputs (+24 V, +12 V, +5 V, -15 V, and –5 V). The
other power converter, in slot 20, the rightmost slot of the RMM, provides a
regulated 5-V/40-A power supply to the RMM shelf.
The group codec (NT2X59AA), at the far left of the RMM shelf in slot 01,
is a required card. This card codes analog samples from the RMM trunk
circuits. The analog samples become PCM code words. This card decodes
the PCM words from the host or RLCM lines. The PCM words become
analog samples.
Provisionable maintenance and service cards
Slots 03–16 of the RMM can be provisioned with various maintenance, test,
and service circuits. The number and types of these cards depend on
engineering needs. These provisionable cards are:
297–8351–550 Standard 04.01 August 1999
Remote metallic test access, remote (MTA) (NT3X09AA). The remote
MTA provides metallic connections between test access points in the line
circuits and testing equipment. The connection consists of a two-wire
metallic matrix with four horizontal buses and eight vertical. One
horizontal bus connects to the MTA bus for the 320 line circuits in
LCA-0 and the other to an MTA bus in LCA-1. Two horizontals are not
used. The verticals connect to service circuits or spare line circuits.
Host office circuits provide MTA functions during normal RLCM
operation.
Metallic test access (MTA) (NT3X09BA). The MTA performs the same
functions as the 3X09AA and has eight horizontal buses and eight
vertical buses.
Scan detector card (NT0X10). The scan detector (SC) card provides an
interface where the DMS-100 Switch Alarm System software can
monitor the state of the RLCM hardware. The DMS-100 Switch Alarm
System software monitors the state of the RLCM hardware to detect
alarm conditions or manually controlled operations. The SC card
consists of two circuits, each is an SC group. Each SC group comprises
seven SC points. Each SC point connects one circuit that the system
monitors for a change in state.
Signal distribution card (NT2X57). The signal distribution (SD) card
provides an interface between DMS-100 Switch Alarm System software
and relay-controlled equipment. The interface enables the activation of
visual and audible alarms. The SC card serves as a monitor, and the SD
card serves as an alarm driver. The SD card consists of two circuits,
each is an SD group. Each SD group consists of seven SD points. Each
SD point connects one visual or audible alarm.