Fujitsu FLM 150 ADM Maintenance And Trouble Clearing page 71

Maintenance and Trouble Clearing
FJTU-320-515-480
Table 3-46: LOS (Loss of Signal)—Alarm Event (cont'd)
AID
Direction
Type
OC12
RCV
150 ADM
OC-3/
OC-12
DROPPED
SIGNAL
OVTG
TRMT
150 ADM
OC-3/
OC-12
ADDED
SIGNAL
T1 NA
TRMT
(LC1A-D1,
LC1A-D1E, or
LC1A-D1E2
unit installed)
T3 TRMT
Issue 9, May 1999
Probable Cause
An OC-12 loss of • Check the upstream ADM for optical channel unit
signal failure/removal.
• Check the fiber link and perform trouble analysis
procedures as necessary.
• Verify the local receive and remote transmit optical
levels.
• Verify good optical connections to the local and far-end
OC-3 units and at the LDF panels along the link. See
Section 5.1, Handling Fiber Cables, and Section 5.2,
Cleaning, Connecting, and Disconnecting the Optical
Connectors.
An OVTG loss of • Check the remote FLM 6 for OVTG unit removal.
signal
• Refer to Section 5.3, Measuring Optical Power, to
measure the local receive and remote transmit levels.
• Clean the optical connectors. See Section 5.1, Handling
Fiber Cables, and Section 5.2, Cleaning, Connecting, and
Disconnecting the Optical Connectors.
• Check the fiber link and perform trouble analysis
procedures as necessary.
A loss of signal • Check the DS1 clock signal cable connections.
caused by a
• Refer to the timing source vendor documentation for
timing supply
procedures to isolate and repair the failure.
failure or a DS1
cable failure
A loss of signal Perform far-end site trouble analysis.
caused by a
timing supply
failure or a DS1
cable failure
A loss of signal • Verify that the cable connections between the DSX-3 and
caused by a DS3 NE are secure.
NE failure on an
• Initiate trouble analysis procedures for the DSX-3 or
incoming DS3
asynchronous equipment site.
• Replace the DS3 cable.
FNC and FNC Customer Use Only
Suggested Corrective Action
3.48: LOS
Vol. ll, Page 480.3-29