Fiber optic transceiver is an Ethernet transmission media conversion unit that exchanges short-distance twisted-pair electrical signals and long-distance optical signals. It is also called a photoelectric converter (Fiber Converter) in many places.
1. The Link light does not light up
(1) Check whether the optical fiber line is open;
(2) Check whether the optical fiber line loss is too large, which exceeds the receiving range of the equipment;
(3) Check whether the optical fiber interface is connected correctly, the local TX is connected to the remote RX, and the remote TX is connected to the local RX. (d) Check whether the optical fiber connector is properly inserted into the device interface, whether the jumper type matches the device interface, whether the device type matches the optical fiber, and whether the transmission length of the device matches the distance.
2. The circuit Link light does not light up
(1) Check whether the network cable is open;
(2) Check whether the connection type matches: network cards and routers and other equipment use crossover cables, and switches, hubs and other equipment use straight-through cables;
(3) Check whether the transmission rate of the device matches.
3. Serious network packet loss
(1) The electrical port of the transceiver and the network device interface, or the duplex mode of the device interface at both ends do not match;
(2) There is a problem with the twisted pair cable and the RJ-45 head, so check;
(3) Fiber connection problem, whether the jumper is aligned with the device interface, whether the pigtail matches the jumper and the coupler type, etc.;
(4) Whether the optical fiber line loss exceeds the receiving sensitivity of the equipment.
4. After the fiber optic transceiver is connected, the two ends cannot communicate
(1) The fiber connection is reversed, and the fiber connected to TX and RX are swapped;
(2) The RJ45 interface and the external device are not connected correctly (pay attention to the straight-through and splicing). The optical fiber interface (ceramic ferrule) does not match. This fault is mainly reflected in the 100M transceiver with photoelectric mutual control function, such as the APC ferrule. The pigtail connected to the transceiver of the PC ferrule will not communicate normally, but it will not affect the non-optical mutual control transceiver.
5. Turn on and off phenomenon
(1). It may be that the optical path attenuation is too large. At this time, an optical power meter can be used to measure the optical power of the receiving end. If it is near the receiving sensitivity range, it can be basically judged as an optical path failure within the range of 1-2dB;
(2). It may be that the switch connected to the transceiver is faulty. At this time, replace the switch with a PC, that is, two transceivers are directly connected to the PC, and both ends are PING. If it does not appear, it can be basically judged as a switch. Fault;
(3). The transceiver may be faulty. At this time, you can connect both ends of the transceiver to the PC (don’t go through the switch). After both ends have no problem with PING, transfer a larger file (100M) or more from one end to the other, and observe Its speed, if the speed is very slow (files below 200M can be transferred for more than 15 minutes), it can be basically judged as a transceiver failure
6. After the machine crashes and restarts, it returns to normal
This phenomenon is generally caused by the switch. The switch will perform CRC error detection and length verification on all received data. If the error is detected, the packet will be discarded, and the correct packet will be forwarded.
However, some packets with errors in this process cannot be detected in the CRC error detection and length check. Such packets will not be sent out or discarded during the forwarding process. They will accumulate in the dynamic buffer. (Buffer), it can never be sent out. When the buffer is full, it will cause the switch to crash. Because at this time restarting the transceiver or restarting the switch can restore the communication to normal.
Post time: Dec-06-2021