The ODW-632 is a fiber optic modem that can be used to create either redundant ring or multidrop fiber optic solutions for devices with RS-422/485 interfaces.The ODW-632 is designed for harsh industrial usage as well as road or railway installations meeting industrial level EMC specifications and having a wide operating temperature range.The maximum distance of a fiber link depends on selected transceiver and fiber type.Fiber distances up to 80 km (50 miles) are possible on each leg of the ring meaning huge rings over 1000 km (621.4 miles) in circumference could be created.The unit has a retiming function that eliminates the problem of jitter and hence ensures reliable communications in all situations.The unit has LED indication to display fault conditions as well as relay contacts that can be connected to a PLC or similar device to allow network failures to be diagnosed at a central point.It is possible to mix ODW-632 with ODW-622 in a network and hence haveboth RS-232 and RS-422/485 devices in the same network. For a multidrop network it is possible to use the ODW-621 or ODW-631 as the endpoints.