U-485 USB Installation and User Manual
Software Installation:
- Support 
Windows 2000/XP/2000, MAC OS-9/X, Linus 2.40 or above
- USB V.1.1 and USB 
2.0
- USB supply power for the converter
- UART 300bps~1Mbps, auto 
tuning
- UART data: 5,6,7,8 bits
- UART data position: odd/even, mark, 
blank, no parity
- UART data stop position: 1, 1.5, 2 bits
Installation of 
USB Converter:
1) Insert the Drive CD-Rom into the CD-Rom Drive
2) Plug in 
the converter into your computer’s USB port
3) Your computer system will ask 
you for this device’s driver location. Please point the location
of the 
driver file as the CD-Rom
4) Computer system will update the driver list and 
install the USB converter automatically.
This will create a virtual com port 
on your PC. When USB converter is connected to
computer, the USB port is 
there.
5) To check if the USB converter is installed successfully or not, 
please follow the next step.
1) go to your computer’s Control Panel
2) 
click on System
3) click on Hardware
4) click on Device Manager
5) 
click on Ports (COM & LPT)
6) while there, unplug the USB device you just 
installed. If a Comp Port disappear under
the Port (COM & LPT), then you 
installed the USB converter successfully. Make sure to
note which COM # is 
the USB converter.
Uninstall the USB Converter:
1) unplug the USB 
converter from the computer
2) got to Add and Remove Software panel from your 
Control panel. Choose
“USB Serial Converter Drivers” and click on 
Remove.
Hardware Installation:
RS485 wiring instruction
Signal 
Wiring
D+ RS485 signal +
D- RS485 signal -
SG RS485 ground
FG 
Connect to the ground
Major Specification:
1) USB port provide power, no 
need other power supply
2) Output is 2 wire half duplex RS485 
connection
3) Wire should be more then 0.5mm in diameter
4) Max 
communication distance is 3000M(4800bps), 
2000M(9600bps),
1000M(115.2Kbps)
5) Max communication network is 32 
points
6) Communication speed is 300bps~1Mbps
7) Support UART: Data 
position 5,6,7,8. Stop Position: 1,1.5,2. Comparison 
Postion:
odd/even/mark/blank/no parity
8) Surge protection: Can with stand 
up to 600W voltage surge, protection from static
voltage and thunder
9) 
Installation method: 35mm standard din rail
10) Working temperature: -20 to 
70C
11) Size: 65X22X12mm
Converter Application:
U-485 can be used in 
point to point or to multiple point network. Beside can
connection to other 
RS-485 connection, it can also connection up to 32 PC’s USB
converter to make 
a RS-485 network. Communication distance between PC can be up
to 
3000M(4800bps), 2000M(9600bps).
Notes:
1) For wiring, wire diameter should 
be more than 0.5m or above, should have at least
120 ohm resistance.
2) 
The length of the cable from point to point should not be longer than 15M.
3) 
When using U-485 and other RS485 connection, pls make sure the last 
RS485
device use a 120 ohm terminating resistor and two 1K resistor. Please 
see the below
picture.