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Overview
Introduction
The TCF-142-RM series fiber converters are slide-in modules that can be
installed in the NRack System’s rackmount chassis, such as the TRC-190
series. The slide-in module is equipped with a multiple interface circuit
that can handle RS-232 or RS-422/485 serial interfaces, and multi-mode
or single-mode fiber. The TCF-142-RM series slide-in modules are used to
extend serial transmission distance up to 5 km (TCF-142-M-XX-RM, with
multi-mode fiber) or up to 40 km (TCF-142-S-XX-RM, with single-mode
fiber).
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. Furthermore, radio and satellite communication signals can be
captured easily for decoding. 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.
No Configuration Required for Baudrate Settings
The TCF-142-RM slide-in modules work under any baudrate from 50 bps
to 921.6 Kbps. The TCF-142-RM slide-in modules simply convert the
signal back and forth between serial (RS-232, RS-422, or RS-485) and
fiber, and since the TCF-142-RM slide-in modules do not need to interpret
the signal, it does not need to know the baudrate of the transmitting
device. For this reason, the TCF-142-RM slide-in modules do not have any
DIP switches or jumpers for setting the baudrate.
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
TCF-142-RM slide-in modules for “ring mode” by setting DIP switch “SW3”
to the “On” position. The Tx port of a particular TCF-142-RM slide-in
modules unit connects to the neighboring converter’s Rx port to form the
ring. Note that when one node transmits a signal, the signal travels
around the ring until it returns to the transmitting unit, which then blocks
the signal. Users should ensure that the total fiber ring length is less than
100 km when using either single-mode models or multi-mode models.
