Nortel DMS-100 Series Maintenance Manual page 38

2-18 Star Remote System hardware
The following table identifies the status indicators on the FSP front panel.
Table 2-5 FSP status indicators
Indicator name
CRITICAL Critical
alarm)
MAJOR (Major
alarm)
MINOR (Minor alarm)
ABS (DC power)
Alarms card (NTTR74AA)
The NTTR74AA alarms card is behind the NTTR75AA card. The alarms card
contains the alarms circuitry and controls the automatic recovery from low
battery (ARLB) function.
The ARLB capability means if the voltage supply drops below a certain level,
the Star Hub stops functioning but the circuit breakers do not trip. When the
power returns to normal level, the Star Hub automatically recovers. This
capability is especially important because the Star Hub is located at a distance
from the host office.
297-8353-550 Standard 05.01 March 2001
Circuit card LED color
NTTR75AA Red
NTTR75AA Orange
NTTR75AA Yellow
NTTR75AA Green
Function
Identifies the following failures:
• The -48 V talk battery supply is missing.
• Both RCPs are removed.
• All four power converter circuit breakers
or the two primary circuit breakers
(PWS00 and PWS10) are OFF.
• The two secondary circuit breakers
(PWS01 and PWS11) are OFF.
• Both ringing generators have failed.
Identifies the following failures:
• fuse failure
• ringing generator failure
• alarm battery supply (ABS) power
failure
• main power is below 41 V.
Identifies a UMP failure (one or more)
Indicates the presence of ABS power