NPT-1020 Installation and Maintenance Manual
Maintenance
ECI Telecom Ltd. Proprietary
7-10
No. Symptom
Probable cause
Corrective actions
Corresponding optical
transmitter may have
been turned off by the
ALS function (see the
following note)
Check that all the fibers are properly
connected to the corresponding optical
transceiver.
When available, select
Maintenance >
Laser Management > Laser Switch > Force
Laser On
in the LCT-APT to activate the
corresponding laser.
Use an OPM to measure the output optical
power. If the output optical power is not
within the range of minimum and
maximum levels specified in the NPT-1020
System Specifications during a 90-second
period, the problem is in the transmit side
of the transceiver. Remove and reinsert
the transceiver.
Check the output optical power again. If
the output optical power is still not within
the range of minimum and maximum
levels specified in the NPT-1020 System
Specifications, replace the transceiver.
If the problem persists, check the received
optical power with an OPM. If the optical
power is within the range of minimum and
maximum levels specified in the NPT-1020
System Specifications, replace the
transceiver.
If the problem persists after following the
previous steps, check the remote site.
If there are no problems on both sites, the
problem may be in the optical fiber
between the two sites.
N
OTE
:
Be sure to turn on the ALS function
after performing all checks.
N
OTE
: An optical port with ALS capability turns off its transmitter when the corresponding
receive signal is lost. Turning the transmitter off may cause a chain reaction, which turns the
optical signals off in a whole section of the network and generates a large number of alarms.
As a result, it may be difficult to identify the real cause of the problem, and you may need to
use the management station log records to identify the port.
