Everything is wired correctly but it still doesn't work...

• Fiber connected in reverse
• Reflection due to fiber length
• Wrong type of fiber
• Poorly terminated connectors on fiber
• Fibers not properly seated in the link connectors
• Trying to overextend the maximum distance
• Baud rate is too high
• IEDs are not operating at the same data rate
• Wrong voltage powering the link
• Connecting to a non-compatible, non-Dymec Link fiber converter
• Using a 232 link on a 2-wire 485 port or vise-versa
• Network requires handshaking, and unit doesn't support it
• Polling is constant so light on/off cannot be differentiated

232 Links

• DCE or DTE switch in wrong position
• REP or OFF switch in wrong position

422/485 Links

• NOR or INV switch in wrong position
• HD or FD switch in wrong position
• REP or OFF switch in wrong position

Problems with loop configuration...

• Master cannot accept/filter its own poll packet
• Repeat switches are not all set correctly
• Trying to use an Optical Star in the loop
• Connecting to another brand of fiber converter

Problems with bus configuration...

• Each copper segment of the bus not terminated on both ends
• Transmit and receive fibers crossed in the network
• Too much noise due to long copper wire lengths
• More than 3 devices on a 485 bus may cause a problem due to the biasing resistors

Ethernet Links

• Either the crossover port or the straight through port can be used, not both
• Cannot connect a 10 Base unit to a 100 Base unit
• Cannot be used with our Serial Links