User Manual

Cabinet descriptionNortel Networks Confidential 1–139
S8000/S8002/S8006 BTS Reference Manual
However, battery output voltages decrease over time.
So, when the battery output voltage reaches the first Load1 threshold, the PCU cuts
off power supply to the boards in the cabinet which are connected to outputs 1 and
3. An alarm signal is generated on the Load1 threshold output.
If the battery output voltage continues to decrease and reaches the second Load2
threshold, the PCU cuts off power supply to the boards in the cabinet which are
connected to outputs 2 and 4.
The Load2 threshold is the minimum permissible voltage at battery output:
typical value of Load1 threshold: 45 V (±2%)
typical value of Load2 threshold: 42 V (±2%)
If the SRU recovers power supply, the batteries are charging. When voltage is equal
to 50.7 V, the PCU reconnects the cabinet boards with its four outputs.
Alarms
Alarm signals from the rectifiers in the energy subrack are concentrated in 3 single
signals determined by logic OR:
ac fault alarm
dc fault alarm
overtemperature alarm
Extreme temperature signals from the CEATS 1
A short circuit between the two CEATS 1 pins of the HOST interface connector
causes the disconnection of all outputs connected to the rectifiers and to the batteries
(only for the S8000 Outdoor BTS), and the generation of the Load1 alarm signal.
From –40°C (–40°F) to 0°C (32°F), the rectifiers accept the mains voltage without
deterioration, but do not function.