1. First, check whether the indicator light of the optical fiber transceiver or optical module and the indicator light of the twisted pair port are on?

A. If the optical port (FX) indicator of the transceiver is not on, please confirm whether the optical fiber link is cross-linked? One end of the fiber jumper is received in parallel; the other end is connected in cross-connection.

B. If the optical port (FX) indicator of the A transceiver is on but the optical port (FX) indicator of the B transceiver is not on, the fault is at the A transceiver side: one possibility is: A transceiver (TX) optical transmission The port is broken, because the optical port (RX) of the B transceiver cannot receive the optical signal; another possibility is: there is a problem with the optical fiber link of the optical transmission port of the A transceiver (TX) (optical cable or light jumper may be broken).

C. The twisted pair (TP) indicator light is not on, please confirm whether the twisted pair connection is wrong or the connection is wrong? Please use a continuity tester to test (but the twisted pair indicator of some transceivers must wait for the optical fiber chain Lights only after the road is connected).

D. Some transceivers have two RJ45 ports: (To HUB) means that the connection line connecting the switch is a straight-through line; (To Node) means that the connection line connecting the switch is a crossover line.

E. There are MPR switches on the side of some transceivers: it means that the connection line connected to the switch is in a straight-through mode; DTE switch: the connection line connected to the switch is in a crossover mode.

2. Are the optical cables and optical fiber jumpers broken?

A. Optical cable on-off detection: Use a laser flashlight, sunlight, or illuminator to illuminate one end of the optical cable connector or coupler; see if there is visible light at the other end? If there is visible light, it means that the optical cable is not broken.

B. On-off detection of optical fiber connection: use laser flashlight, sunlight, etc. to illuminate one end of the optical fiber jumper; see if there is visible light at the other end? If there is visible light, it means that the optical fiber jumper is not broken.

3. Is the half/full duplex mode wrong?

Some transceivers have FDX switches on the side: full duplex; HDX switches: half duplex.

4. Detect with an optical power meter

The luminous power of the optical fiber transceiver or optical module under normal conditions: multi-mode 2Km: between -10db-18db; single-mode 20km: between -8db-15db; single-mode 60km: between -5db-12db; if When the luminous power of the optical fiber transceiver is between: -30db-45db, it can be judged that there is a problem with the transceiver.