ZyXEL Communications Multi-service Access Platform MSAP2000 - Manual (Page 219)

9. Network Management System (NMS) Functions
MSAP2000 Technical Manual V3.0 9-5
LEDs on the faceplate of the MPM Module can indicate power
alarms, main alarms, minor alarms, and near and far end alarms.
All COT and RT Module faceplates will have LEDs that can
indicate power, alarm, and loop status.
Alarm Cut-off
Mechanism
The COT’s Alarm Cut-off mechanism supports Alarm Cut-off,
when necessary. During Alarm Cut-off, other Alarm reports can
still be initiated and sent.