Nortel DMS-100 Series Maintenance Manual page 71

NTTR71AA line maintenance unit
The NTTR71AA line maintenance unit (LMU) card is a digital signal
processor controlled by the SMC. The LMU does not require a separate load.
Instead it is loaded as part of the SMC loadfile. The LMU
• supports line metallic and loop maintenance for ISDN and POTS lines
• supports temperature and humidity measurements for those Star Modules
that are in an SRMO cabinet
• reports the temperature and humidity measurements and alarms to the scan
and distribution points
• monitors battery voltage and charging activities
• does not support MONTALK interface for monitoring or talking to a line,
meaning the Star Module does not support the MONTALK capability
The CC and the LMU communicate through the Star Hub. If the LMU fails,
or there is a communication failure between the SMC and the LMU, the Star
Module goes in-service trouble (ISTb). In addition, a major alarm is output for
the Star Module.
NTTR72AA power supply and ringing card
The NTTR72AA power supply and ringing card is in two slots in the TSS and
supplies
• +5 V and +15 V to the SMC and LMU from the -48 V input
• 12.7 V, 130 V, 52 V coded ringing voltage to POTS lines
• +5 V ISDN power to ISDN line cards, if installed
The power supply has the following features:
• output overvoltage protection
• input dc voltage from -40 to -60 V dc
• output current overload and short circuit protection
• +5.1 V and +15 v over and undervoltage detection. When the monitor
detects a failure, the circuit is stopped.
• faceplate mounted LED provides power supply OK indication
• coin current detector
• ring multiplexer
• coin multiplexer
The coin and ringer function of the card provides four dc voltage outputs that
are used for coin functions.
DMS-100 Family NA100 Star Remote System XPM15 and up
Star Remote System hardware 2-51