WL
-
430T 4G Wireless Modem with all function
UserManual
23
3.5
Rs485 Serial port installation
The RS-485 interface requires a single two or three wire cable. The Common
connection is optional, depending on the RS-485 network devices used. The
cable required for this interface is shown below:
RS485 +
TX+ / RX+
RS485 -
IO Terminal
TX- / RX-
Note:
Terminating resistors are generally not required on the RS-485
network, unless
you are experiencing communication problems that can be
attributed to signal echoes or reflections. In these cases, installing a
120-ohm terminating resistor between pins Rs485+ and Rs485- on the
module connector end of the RS-485 line may improve communication
quality.
RS-485 and RS-422 Tip
If communication in the RS-422 or RS-485 mode does not work at first,
despite all attempts, try switching termination polarities. Some
manufacturers int and -, or A and B, polarities differently.
3.6 LED indicators
LED
Color
Status
Description
DO-2
Green
Steady
Digital Output signal No.2 is Closed
Unlighted
Digital Output signal No.2 is Open
DO-1
Green
Steady
Digital Output signal No.1 is Closed
Unlighted
Digital Output signal No.1 is Open
DI-2
Green
Steady
Digital input signal No.2 is Closed
Unlighted
Digital input signal No.2 is Open
