User Manual

44
User Manual
TFAx
CaseA
Fig. 3.16 (c): Flow-chart describing the fibre optic DL troubleshooting
start
Is there any
point where the
fibre experiences
a small radius of
curvature?
Rearrange the optical path to avoid
sharp bends. If necessary replace the
optical cable with a longer one.
Is red LED
upon remote
unit still ON?
Are SC-APC
connectors properly
installed at both fibre
ends?
Fix better SC-APC
connectors
Yes
N
o
N
o
Y
es
No
Y
es
N
o
Y
es
Disconnect the optical
SC-APC connector from
remote unit DL port
Clean optical SC-APC
ports on both TFL
N
and remote uni
t
.
Disconnect fibre optic
and clean it at both ends.
Reconnect the fibre
to relevant ports
Measure the output power
at corresponding fibre end.
Measure the input power
coming out of the TFLN
DL port.
Disconnect optical SC-APC
connector from TFLN DL
port.
Calculate DL fibre attenuation
A
DL
[dB]=input power - output power
Is A
DL
> 4dB?
Fibre optic cable has some
problems. Replace it.
Troubleshooting procedure has
not identified the problem. Refer
to supervision system or contact
assistance
end
No
Y
es
No
Y
es
Is red LED
upon remote
unit still ON?
Is red LED
upon remote
unit still ON?
Go to TFLN
side.