Alarm Lists. Regenerator section (B1) excessive errors. The board alarm indicator flashes once every other second. Regenerator section (B1) signal degraded, страница 8

Item

Description

Alarm Name

R-LOF

Name

Loss of frame

Alarm Level

Critical

Alarm Category

Communication alarm

Alarm Board

TWF/TWC/RWF/RWC/LWC/OCU

Alarm Indication

The alarm indicator of board flashes three times every other second

Alarm Reasons

(1) The attenuation of the receiving signal is excessive.

(2) There is no frame structure in the signal transmitted from opposite station.

(3) Fault occurs in the receiving direction of this board.

Processing Methods

(1) Observe from NM whether the alarm is accompanied with R-LOS alarm; if yes, it indicates that no signal is sent to the board.

(2) Measure the input optical power; if it is normal, check whether the connector is loosened and is dirty; if not, the board might be faulty. Replace the board.

(3) If the optical power is close to 0W, measure the optical power of access SDH equipment transmitting end; if it is normal, the fault might be in the connected fiber pigtail section; if it is abnormal, the fault is in the SDH equipment. Replace the faulty unit.

(4) If OTU detects R-LOF alarm, measure the output optical power of OTU in opposite station and check according to steps 2 and 3.

(5) The self-loop of board can be made to judge whether the board is faulty.

Remarks

Item

Description

Alarm Name

R-LOS

Name

Loss of signal

Alarm Level

Critical

Alarm Category

Communication alarm

Alarm Indication

The alarm indicator of board flashes three times every other second

Alarm Board

TWF/TWC/RWF/RWC/LWC/OCU

Alarm Reasons

(1) The optical fiber is broken；

(2) The attenuation of optical path is too large；

(3) Fault occurs in the transmitting part of opposite end, the line transmitting failure；

Processing Methods

(1) Measure the input optical power. If the optical power is normal, check whether the optical connector is loosened and is dirty. if not, the board might be damaged. Replace the board.

(2) If the optical power is close to 0W, measure the optical power of access SDH equipment transmitting end; if it is normal, the fault might be in the connected fiber pigtail section; if it is abnormal, the fault is in the SDH equipment. Replace the faulty unit.

(3) If OTU detects R-LOS alarm, measure the output optical power of OTU in opposite station and check according to steps 1 and 2.

(4) The self-loop of board can be made to judge whether the board is faulty.

Remarks

Item

Description

Alarm Name

R-OOF

Name

Out of frame

Alarm Level

Critical

Alarm Category

Communication alarm

Alarm Board

TWF/TWC/RWF/RWC/LWC/OCU

Alarm Indication

The alarm indicator of board flashes three times every other second

Alarm Reasons

(1) The attenuation of received optical signal is too large;

(2) The bit error is too large during transmitting;

(3) Fault occurs in the transmitting part at the opposite end;

(4) Fault occurs in the receiving part at home station.

Processing Methods

The method is the same as that of R-LOF.

Remarks