User Manual
Modbus/BACnet IP Gateway
GT200-BM-2RS
WWW.SSTCOMM.COM
11
B+
A-
GND
1
2
3
485+
485-
RS485 Equipment
RS485 Interface
RS485 Equipment
RS485 Equipment
485+
485-
485+
485-
…
When RS485 communicates under the point-to-multipoint mode, in order to prevent the reflection and
interference of the signal, it requires connecting a terminal resistor in the farthest two ends of the each line; the
parameter is 120Ω 1/2W. There are no parallel terminal resistors at the serial port side of GT200-BM-2RS.