__Power trouble occurs.

Checking method:
a) Check whether the link is cut down ;
b) Check whether the optical attenuation is too much that beyond the default range of the equipment;
c) Check whether the connection of the ports is correct, for example, the connection between local TX interface and remote RX interface, or the connection between remote TX interface and local RX interface;
d) Check whether the optical connector is correctly inserted into the interfaces of equipment, whether the jumper model is matched with the equipment, whether the equipment model is matched with the fiber, whether the transmission distance is beyond the default distance of the equipment.

Checking method :
a) Check whether the network line is broken ;
b) Check whether the connection is correct: network card and router etc applies crossover cable ; switch and hub etc applies straight-through cable ;
c) Check whether the transmission rate is matched .

Checking method :
a) The electric port of the media converter is mistakenly connected with the interfaces of network equipment, or the duplex working mode of the two ports can not be matched ;
b) There might be trouble existed in the twisted-pair or RJ-45 connectors ;
c) It is possible that the fiber is not correctly connected, for example, jumper lead is not firmly connected with equipment interface; or tail fiber , jumper lead and the coupler model etc can not match.

a) TX and RX is reversely connected ;
b) RJ45 interface is mistakenly connected with exterior equipment .

a) Too much optic attenuation. At this time, you can use optical power meter to test the optical sensitivity, if the result is very close to or beyond the sensitivity standard, the trouble probably lies in the optical link ;
b) It is possible that trouble occurs at the switch which connected with the converter: please replace the switch as PC, that means the couple of converters are directly connected with PC, if the communication is OK, we can deduce that the trouble occurs at the switch ;
c) The trouble might happen at the converter itself: directly connect two PC through a converter, try to transmit a file (above 100M), if the transmission rate is too small, we can deduce the trouble lies in the converter itself .

__The problem is because of the switch. During the transmission process, switch will handle the CRC and length check, if any error exists in the packet, the error packet will be discarded, and the correct packet will be transmitted. However, during the process it is possible that the error which exists in the packet can not be checked out, at this time, the packet can neither be transmitted nor to be discarded, they will be accumulated in the buffer, when the buffer is chocked by the packets, it is possible that the switch can not work normally .

If any connection problem occurs on the media converter, please do the test according to the following tips .
a) Local test:
Make direct communication between the computers of two ports through a converter, if the communication is normal, the converter is ok. Otherwise we can deduce that the trouble is due to the media converter .
b) Remote test:
Make direct communication between the computers of two ports through a converter, if the communication can not be carried out, please check the connection of optical channel, or the optical power and the optical sensitivity is within the default range. Otherwise, if the communication is normal, it is probably that the problem happens in the switch.
c) Do remote test to diagnose where the trouble happens:
Replace the computer of one port with switch, then carry out the communication, if the communication is ok, it is possible that the problem happens at the remote switch.

__Equipment can not be electrified, it is possible that the power is not connected correctly, or the power polarity is connected reversely.

__Can not receive optical signal, it is possible that the fiber is broken, or no optical signal transmit from the remote terminal.

__Can not receive normal frame signal, please check the optical link and equipment.

__Can not receive 2M signal, please check the cable quality, and whether the TX/RX are connected reversely.

__Alarm happens at the local equipment, it is possible that before processing the trouble, a screen processing has been done.

__Checking method: Do the loop back test, if the indicator is off, please check the connection of E1 input port.

Checking method: The trouble is usually due to the causes mentioned below :
a) Trouble connection of E1 input port;
b) The remote equipment is working under the non-frame status;
c) Trouble happens at the E1 channel, please make a test combined with PT and RLP;
d) Equipment is working under the EXT clock mode, while the exterior equipment clock mode is different with the clock mode of BYCON-B1.

__Checking method: Press LLP switch, if the TD and RD are keep on glittering, the trouble probably lies in the remote terminal. Then press DLP switch to loopback the signal to assist the remote test.

__Checking method: Press PT to loopback the data to local terminal, if the PT indicator can not be lightened, it is probable that there is trouble lies in the E1 transmission channel.

__Checking method: Please ensure that one of the equipment clock mode is set as main clock.

6. When connected with DCE, please take notice that if the DCE is set as inner clock, the local equipment should be set as exterior clock, and if the DCE is set as exterior clock, the local equipment should be set as inner clock.

7. If press PT button of BYCON-B1, the PT indicator can not be lightened. Then press LLP, and the PT indicator is on; At this time you can deduce that the BYCON-B1 is under normal working condition.

8. When a pair of BYCON-B1 are both working under the frame status, firstly press PT button of the local equipment, PT indicator is off, then press RLP of the local or press DLP of the remote terminal, at this time if the PT indicator is on, it is safely to draw a conclusion that both the two BYCON-B1 and the E1 transmission channel are ok.