Common faults and treatment methods of optical fiber transceiver

 

1. Optical fiber The indicator light of the optical port (FX) of the optical fiber transceiver is off:

 

a. Dual optical fiber transceiver: to determine whether the optical fiber link is cross-connected, one end of the pigtail is connected in parallel, and the other end is cross-connected;

 

b. For a single fiber transceiver, if the A-side indicator light is on but the B-side indicator light is off, the fault is at the A side: the cause of the fault is divided into two situations: one is that the A-side optical transmission port (TX) is broken, causing the B-side optical receiving port RX) No signal can be received; second, the fiber link connected to end A is faulty, for example, the fiber or pigtail is broken;

 

c. Check whether the loss of the optical fiber link is too large, which exceeds the receiving range of the equipment (optical power detectors are needed. Generally, if there is a spare core, the spare core is directly replaced, and the original core is considered unusable);

 

d. Check whether the pigtail interface is properly inserted into the transceiver interface, whether the type matches the transceiver, whether the transceiver matches the fiber type, and whether the transmission length matches the transmission distance of the transceiver.

 

2. Twisted pair (TP) indicator light is off:

 

a. Single RJ45 port transceiver: Determine whether the twisted pair connection is normal. Some devices require that the optical fiber link is normal before the twisted pair indicator light is on.

 

b. Dual RJ45 port transceiver: (To HUB) indicates that the cable connecting the switch is a straight-through cable; (To Node) indicates that the cable connecting the switch is a crossover cable.

 

c. The transceiver has an MPR switch, which indicates that the cable connecting to the switch is in a straight-through mode, and the DTE switch indicates that the cable connecting to the switch is in a cross mode.

 

3. Serious network packet loss:

 

a. The RJ45 port of the optical fiber transceiver and the network device interface, or the duplex mode of the interfaces at both ends do not match;

 

b. There is a problem with the twisted pair cable and the RJ45 head;

 

c. There is a problem with the fiber connection: the pigtail is not inserted properly, or the pigtail does not match the coupler.

 

Four, the phenomenon of on and off:

 

a. The attenuation of the optical path is too large, which can be monitored by an optical power detector, and 1-2dB can be determined as an optical path failure;

 

b. If the fiber optic transceiver is faulty, you can connect both ends of the fiber optic transceiver to the PC. After there is no problem with ping, send a larger file (above 200M) from one end to the other end. If the speed is very slow, it can be determined as the transceiver failure;

 

c. If the switch connected to the optical fiber transceiver fails, replace the switch with a PC, that is, the two transceivers are directly connected to the PC, and both ends are PING. If it does not appear, it can be determined as a switch failure.

 

5. Determine whether the fiber or pigtail has been disconnected:

 

Use a laser flashlight, sunlight, etc. to illuminate one end of the fiber jumper; see if there is visible light on the other end. If there is visible light, it indicates that the fiber jumper is not broken.

 

6. Working mode failure:

 

Some transceivers have FDX switches and HDX switches, corresponding to full duplex and half duplex respectively