User Manual

MN021-01
Page 17 of 28
OPTICAL LOSS OPERATION ALARM SEVERITY
0 dB AGC working, constant RF gain none NONE
< 3dB AGC working, constant RF gain none NONE
< 5 dB AGC not working, RF gain
decreases according to 2dB
electrical per 1dB optical
AGC out of range:
red LED flashes
MINOR
> 5 dB
AGC not working, the optical
signal is too low, the receiver is
automatically switched off in
order to reduce the unwanted
noise to the system.
Optical power too
low: red LED
fixed, relays
alarmed.
MAJOR
11. Alarms and settings
11.1. Remote unit LEDs
The TFAF is fully managed and supervised by the local microprocessor. The alarms are fully
managed by software according to different severity levels, and reported as local visual alarms
(LED’s) and on the data link to the local unit.
There are 2 LED on the Local unit, one red alarm LED is related to optical link and internal
failures, one green LED is for the power supply.
Figure 12 Remote Unit TFAF LED’s
REMOTE ALARM DESCRIPTION LED STATUS SEVERITY
UL AGC out of range RED Flashing MINOR
UL optical power too low RED Fixed MAJOR
DL RF amplifier 1 RED Fixed MAJOR
DL RF amplifier 2 RED Fixed MAJOR
Antenna disconnected (DC loop) RED Flashing MINOR
External 1 RED Fixed MAJOR
External 2 RED Fixed MAJOR
11.2. External alarms
Two external alarm contacts are provided. These contacts are open under non-alarm condition.
Figure 13 Remote Unit TFAF Alarm Connectors