Emerson Rosemount 1410S Reference Manual page 28

Installing the Gateway
December 2023
Figure 3-6: Emerson 1410S Gateway and Two 781S Smart Antennas
A. Emerson WirelessHART
B. Attach shield pair cable (Belden 3084A or equivalent)
C. Optional secondary Emerson Wireless 781S Smart Antenna
D. Tape back shield wire and foils
E. Emerson Wireless 1410S Gateway
3.5.4 RS-485
The Gateway can be ordered with an optional RS-485 (serial) connection (see
Modbus
communicate Modbus RTU on an RS-485 data bus.
Use 18 AWG single twisted shielded pair wiring to connect the Gateway to the RS-485
data bus. Ensure the total bus length does not exceed 4000 ft. (1220 m). Connect the Tx
- (negative, receive) wire to terminal A and the Rx + (positive, transmit) wire to terminal
B. Trim the wiring shield close and use insulation to prevent it from touching either the
Gateway enclosure or other terminations.
If the existing data bus uses a 4-wire Full Duplex configuration, see
a 2-wire Half Duplex configuration.
Figure 3-7: Convert from Full to Half Duplex
28
781S Smart Antenna
®
terminals are labeled A and B on the wiring diagram. This connection is used to
®
Tx
Rx
Tx
Rx
Reference Manual
00809-0600-4410
Figure
Figure 3-7 to convert to
(A)
(B)
Emerson.com
3-5).