Product Overview
Install the Drivers
Loopback Test (4 Wire)
Back to Back Test (2 Wire)
Connect the Converter
1
3
4
2
• The program will install the driver and a
screen will be displayed indicating successful
installation.
• When you connect the converter to your
PC for the first time, the COM port will be
configured. This could take up to 30 seconds.
Due to the configuration, a loopback test is
not possible with this model. However, two
converters can be used in a back to back
configuration.
Wire the converters as shown below.
Using HyperTerminal or similar program, connect
to the appropriate COM ports. Set the desired
baud rate. Transmit data. If the same string is
returned the test is good.
RS-485
Side
DB9F
USB Side
Loopback RDA(-) to TDA(-) and TDB(+) to
RDB(+) as shown in the diagram.
Using Hyper Terminal or similar program,
connect to the appropriate COM port. Set the
desired baud rate. Ensure that Hyper Terminal
local echo is OFF. Transmit data. If the same
character string is returned, the test is good.
Use the included CD to install the converter’s
drivers.
Warning: To prevent installation errors, do
not plug in the hardware until you have al-
ready installed the drivers.
The driver software is contained on the CD
that is packaged with your converter.
• Put the driver CD into the PC. The setup
program should automatically launch.
• Click Next. Accept the license agreement
and click Next again.
PIN 2 Data A (-)
PIN 3 Data B( +)
PIN 4 GND
USB
Data A (-)
Data B (+)
GND
To PC
485USB9F-2W RS-485 2-Wire Device
485USB9F-2W Wiring
485USB9F-4W Wiring
USB
To PC
485USB9F-4W
485USB9F-2W
RS-485 4-Wire Device
RS-485 2-Wire Device
Pin 2 RDA(-)
Pin 3 TDB(+)
Pin 7 RDB(+)
Pin 8 TDA(-)
Pin 6 GND
TDA(-)
RDB(+)
TDB(+)
RDA(-)
GND
A detailed description of this test is located in
the technical notes section of our web page,
www.bb-elec.com.