If the light cat LOS light does not light up, it is usually caused by the following situations:

1 There is something wrong with the optical interface of the optical cat, and the optical cat needs to be replaced;

2. The connector of indoor tail fiber connecting optical cat is loose, and it can be restored when the connector is plugged in;

3 Some indoor optical fibers are bent too much. Excessive bending of optical fiber will affect the total reflection transmission of optical signal in optical fiber, as long as the optical fiber is straightened;

4 some outdoor optical fibers are broken or the optical port of the equipment in the computer room is faulty, so it is necessary to contact the staff for troubleshooting.