Fiber Transceiver Frequently Asked Questions

1.Power light is off

electricity failure

2.LOS lights must have the following failures:

(a) The cable from the equipment room to the customer's end has been broken;

(b) The SC pigtail and the fiber transceiver slot are not plugged in or disconnected.

3.Link light does not shine may have the following situation:

(a) Check if the optical fiber line is open circuit

(b) Check whether the optical fiber line is excessively worn and exceeds the receiving range of the device

(c) Check that the fiber optic interface is properly connected, the local TX is connected to the remote RX, and the remote TX is connected to the local RX.

(d) Check if the fiber optic connector is properly inserted into the device interface, whether the jumper type matches the device interface, whether the device type matches the fiber, and whether the device transfer length matches the distance.

4. Circuit Link light is off The fault may have the following conditions:

(a) Check if the network cable is open circuit

(b) Check whether the connection types match: Devices such as network cards and routers use crossover cables, and switches and hubs use direct lines.

(c) Check whether the device transmission rate matches

5. The network packet loss may be seriously faulty as follows:

(a) The electrical port of the transceiver does not match the network device interface, or the duplex mode of the device interfaces at both ends does not match.

(b) Problems with twisted pair and RJ-45 heads, check

(c) The fiber connection problem, whether the jumper is aligned with the device interface, and whether the pigtail is matched with the jumper and coupler type.

6. Both ends of the fiber transceiver cannot communicate

(a) The fiber is reversed, and the fiber connected to TX and RX is reversed

(b) Incorrect connection between RJ45 connector and external device (note straight and twisted connections)

The optical fiber interface (ceramic ferrule) does not match. This fault is mainly reflected in the 100M transceiver with photoelectricity control function. If the tail fiber of the APC ferrule is connected to the transceiver of the PC ferrule, it will not be able to communicate normally. Photoelectric mutual control transceiver has no effect.

7. Time-off phenomenon

(a) The attenuation of the optical path may be too large. At this time, the optical power at the receiving end may be measured with an optical power meter. If the optical sensitivity is within the range of 1-2 dB near the receiving sensitivity range, the optical path failure may be basically judged.

(b) The switch connected to the transceiver may be faulty. At this time, the switch is replaced with a PC. That is, the two transceivers are directly connected to the PC. The two ends are PING. If not, the switch-off phenomenon can be basically judged as the switch failure.

(c) The transceiver may be faulty. At this time, both ends of the transceiver can be connected to a PC (not through the switch). After the two ends have no problem with PING, transfer one large file (100M) from one end to the other and observe it. The speed, such as the slow speed (file transfer below 200M for more than 15 minutes), can be basically judged as a transceiver failure.

8. After a period of communication, it crashes, that is, it cannot communicate. After restarting, it will return to normal.

This phenomenon is generally caused by the switch. The switch will perform CRC error detection and length check on all received data. It will check out the packets with errors and discard them, and the correct packets will be forwarded. However, some erroneous packets in this process cannot be detected in the CRC error detection and length check. Such packets will not be sent during the forwarding process and will not be discarded. They will be accumulated in the dynamic cache. In the buffer, it can never be sent out. When the buffer is full, it will cause the switch to crash. Because restarting the transceiver or restarting the switch at this time can restore the communication to normal, the user usually thinks that the transceiver is a problem.

9. Transceiver Test Method If you find there is a problem with the transceiver connection, test it as follows to find out the cause of the fault.

Dual-fiber transceiver network connection diagram

(a) Near-end test:

Both ends of the computer on the PING, if you can PING通 then prove that the fiber transceiver is no problem. If the near-end test fails to communicate, the fiber transceiver can be judged to be faulty.

(b) Remote test:

The two ends of the computer are PING. If the PING is inconvenient, you must check whether the optical path connection is normal and whether the transmitting and receiving power of the optical fiber transceiver is within the allowable range. If you can PING pass it proves that the light path is connected properly. It can be determined that the fault is in the switch.

(c) Remote test to determine the point of failure:

Connect the switch to the switch first and the two ends to the PING. If there is no failure, you can determine the failure of the other switch.

Fiber Transceiver Technology Development

The level of fiber optic transceivers has been very complete, the repair rate is quite low, manufacturers can generally promise three years replacement, lifetime warranty.