Emerson 781S, Reference Manual

Page: 85 / 134

4.4 Terminating resistors
Please reference the Emerson 1410S Gateway and 781S Smart Antenna
Reference Manual for configuration of the DIP switches.
Three DIP switches are provided to enable termination and biasing resistors
to the serial Modbus connection. The switches are found in the electronics
housing located above the terminal connections. The three DIP switches are
on the right side and the down position in ON.
4.5 Connect to the host system
Procedure
1. Wire the Gateway’s Ethernet 1 (Primary) or Serial Output connection
to the Host System Network or Serial I/O (see Figure 1 and Figure 2
for hardware drawings). This will have to be done for both networks.
You can route the networks to different locations if necessary.
2. For serial connections, make sure all terminations are clean and
secure to avoid wiring connection problems.
4.6 Best practice
Twisted shielded pair cable is generally used to wire the serial connection,
and it is standard practice to ground the shield on the serial host side leaving
the shield floating on the Gateway side. Insulate the shield to avoid
grounding issues.
In accordance with Emerson Wireless HART
®
security guidelines (Emerson
Wireless Security Whitepaper ), the Gateway should be connected to the
Host System via a LAN (Local Area Network) and not a WAN (Wide Area
Network).
Quick Start Guide March 2020
18 Emerson.com