User Documentation

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Overview
Introduction
Weidmüller Serial/Fiber converters are equipped with a multiple interface circuit
that can handle RS-232, RS-422, and RS-485 serial interfaces, as well as a
multi-mode fiber. Serial/Fiber converters are used to extend serial transmission
distance up to 5km.The Serial/Fiber converter must be configured to transmit a
particular serial interface. You cannot transmit both RS-232 and RS-485 signals
at the same time.
Why Convert Serial to Fiber?
Fiber communication not only extends the communication distance, but also
provides many advantageous features.
IMMUNITY FROM ELECTRICAL INTERFERENCE: Fiber is not affected by
electromagnetic interference or radio frequency interference. It provides a clean
communication path and is immune to cross-talk.
INSULATION: Optical fiber is an insulator; the glass fiber eliminates the need for
using electric currents as the communication medium.
SECURITY: Fiber cannot be tapped by conventional electric means and is very
difficult to tap into optically.
RELIABILITY & MAINTENANCE: Fiber is immune to adverse temperature and
moisture conditions, does not corrode or lose its signal, and is not affected by
short circuits, power surges, or static electricity.
Reverse Power Protection
The Reverse Power Protection feature provides extra protection against
accidentally connecting the power cables to the wrong terminal. The converter
automatically detects which power wire is positive and which is negative.
Ring Mode
To allow one half-duplex serial device to communicate with multiple half-duplex
devices connected to a fiber ring, you should configure the Serial/Fiber Converter
for “ring mode” by setting DIP switch “SW4” to the “On” position. The Tx port of a
particular Serial/Fiber Converter unit connects to the neighboring converter’s Rx
port on the ring. Note that when one node transmits a signal, the signal travels
around the ring until it returns back to the transmitting unit, which then blocks the
signal. Users should ensure that the total fiber ring length is less than 100 km.