Nortel DMS-100 Series Maintenance Manual page 31

• scan and distribution points
— 8 user-defined distribution points for each UMP card (SD points
activate audible or visible devices to give information about alarm
conditions) for a total of 16 SD points
— 12 user-defined scan points for each UMP card (scan points detect
problems) for a total of 24 SC points
• ISDN line tests, including
— feed voltage measurements
— dc resistance measurements
— dc capacitance measurements
— foreign voltage measurements
— ISDN protocol tests, where the UMP card acts as an external interface
There are two UMP cards in the Star Hub. When one UMP card is out of
service, the second card takes over responsibility for all subscriber lines. The
UMP card acts as an LTU for measurement tests, as a MTA for metallic test
access to the line, and as a MONTALK/VER90 for monitoring/talking to a
line. The UMP also acts as an alarm scan and distribution circuit.
The UMP details are defined in table RMPCKT.
Ringing generator (NTTR60AA)
The NTTR60AA ringing generator cards reside in slots 01 and 22. The ringing
generators supply ringing voltage to the line drawers. The NTTR60AA
generates ringing signals and the dc voltages required for the automatic
number identification (ANI) and coin functions. The ring output frequency
and amplitude are set manually during installation using the four DIP switches
on the card.
Power converter (NT6X53AA)
There are up to four power converters in the Star Hub control shelf in slots 03,
05, 18, and 20. These power converters
• supply +5 V and +15 V from the -48 V office battery input
• provide a relay multiplexer circuit that selects the ringing voltage generator
that supplies ringing voltage to the line cards
• supply power to all drawers if a single converter fails
Note: The power converters must be installed in matched pairs. This
means an AA version of the NT6X53 must be matched with another AA
version.
DMS-100 Family NA100 Star Remote System XPM15 and up
Star Remote System hardware 2-11