Tritex 1 Installation and Setup
126
09/27/12
PN: 27666
Exlar Corporation
Rev. M
952-500-6200M
Model TTUSB485 USN to 485 Introduction
Supporting 2-wire RS-485 or a 4-wire RS-422/485 communications, this device is well suited for
any application that requires long range or multi-drop capabilities. The TTUSB485 model uses
pluggable terminal blocks on the RS-422/485 side and has a pair of LEDs that indicate data
being transmitted or received. Model TTUSB485 includes special circuitry that adds 2000 volts
isolation protection against ground loops and voltage spikes; and it draws power from the USB
port so no power supplies is required.
Simply plug the converter into an available USB port on your computer or USB hub and the
device will show up as an additional COM port in the Windows Device Manager. Configured as
an additional COM port, the converter is now compatible with your Windows applications.
Universal Serial Bus (USB) has become the connectivity workhorse of today’s PCs, replacing
the familiar serial ports. But many commercial and industrial devices still use RS-422/485
interfaces. To connect these devices to modern PCs you need robust and reliable conversion
solutions. At the same time, USB ports are becoming more common on commercial and
industrial equipment such as point-of-sale peripherals, medical devices, scientific
instrumentation, laboratory equipment and other devices. Sometimes these are used in
environments where surges, spikes and ground loops are likely to occur.
Features
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2000 V RMS optical isolation
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15kV EDS surge protection
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Adds a COM port to your PC
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Protects against surges, spikes and ground loops
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LEDs for transmit and receive lines
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USB 1.0, 1.1 and 2.0 compatible (12 Mbps)
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Automatic configuration on Windows 98, ME, 2000, XP, Vista
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No power supply required (powered from USB bus)
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Includes 1 meter USB cable
RS-485 Control
No special software is required to control the RS-485 receiver or transmit line driver. The driver
is automatically enabled during each byte transmitted in RS-485 mode. The transmitter is
always enabled in RS-422 mode. The receiver is tri-stated during each byte transmitted in the
echo-off mode. The receiver is always enabled in the echo-on mode. There are 4.7k Ohm pull-
down resistors on the RDA and RDB lines. A termination resistor may be added to R16 if
needed.
