Introduction, Presentation – ABUS Technologies RS485-USB Converter User Manual
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ABUS TECHNOLOGIES INC.
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RS485-USB
1. INTRODUCTION
The RS485-USB module is a cost-effective way to convert RS485 or RS422
industrial buses to a USB interface. When connected to a PC USB port the RS485-
USB module is automatically detected and is installed as a native COM port, which is
compatible with any existing serial communication application.
Multiple modules can be installed when using USB hubs thus allowing a hassle-
free configuration of a multi serial system without any IRQ or DMA configuration. 1500
Vdc isolation between the USB port and RS485/RS422 protects the PC from spikes or
possible misconnections in the communication bus.
2. PRESENTATION
Technical Parameters
The RS485-USB converter can be configured for four-wire (Full Duplex) RS422 and RS485 or
two-wire (Half Duplex) networks. When operating in two-wire RS485 the data transfer control is
automatically done by the converter. Two independent and isolated RS485 networks can be supported
by one RS485-USB module thus duplicating the possible number of remote devices.
Computer interface:
USB V1.1 Plug and Play.
Operational system virtual serial port driver. Supports Windows 98/ME/XP/2000/CE, MAC &
Linux 2.4.20 or superior.
Field Interfaces:
RS485 Half Duplex (dual buses), RS485 Full Duplex or
RS422.
Jumper selected:
RS485 / RS422.
Automatic flow control for RS485 Half Duplex.
120 Ohms internal resistors termination enabled by jumpers.
Data rate:
From 300 bps to 1 Mbps.
Maximum RS485/RS422 cable length:
1200 m
Maximum number of devices in the RS485 network (unit load devices – 12 k):
Half Duplex: 2 x 32 devices
Full Duplex: 32 devices
Data transmission and reception LED indicators
Power:
From the USB port. Consumption: <100 mA.
Isolation:
1500 Vdc (1 minute) from USB interface and the
RS485/RS422 interface.
RS485/422 bus protection:
±60 Vdc, 15 kV ESD.
USB connection:
Mini-B connector. A 1.5 m cable with plugs mini-B and A is
provided with the module.
RS485/422 connector:
Screw terminal type accepting 1.5 mm² (16 AWG) wires.
Operating environment:
0 to 50°C, 10 to 90% relative humidity, non-condensing.
ABS enclosure:
70 x 60 x 18 mm.