Emerson Process Management 3422 User Manual
116
RS-485 serial connection setup
Section 5: Startup and meter configuration
Reference, Installation, and Operations Manual
June 2013
3-9000-743 Rev S
c.
To configure Port B for RS-485 Full Duplex operation, set the switches as
indicated in the table below (
for switch bank locations):
d.
To configure Port B for RS-485 Half Duplex operation, set the CPU board and
Field Connection board switches as indicated in the table below (
for switch bank locations):
Table 5-8 Serial Port B RS-485 full duplex configuration switch settings
Board
Switch
Position
CPU
S4-1
RS485
S4-2
RS485
S5-2
FULL
S7-1
RS485
S7-2
RS485
Field Connection
Termination On
Termination Off
S1-5
TERM ON (RX)
TERM OFF (RX)
S1-6
TERM ON (TX)
TERM OFF (TX)
S1-7
FULL DUPLX
NA
S1-8
FULL DUPLX
NA
Table 5-9 Serial Port B RS-485 half duplex configuration switch settings
Board
Switch
Position
CPU
S4-1
RS485
S4-2
RS485
S5-2
HALF
S7-1
RS485
S7-2
RS485
Field Connection
Termination On
Termination Off
S1-5
TERM ON
TERM OFF
S1-6
TERM OFF
TERM OFF
S1-7
HALF DUPLX
S1-8
HALF DUPLX
Termination should only be enabled if the meter is the last drop in a multi-drop
configuration or the only meter in a single-drop configuration.
configuration or the only meter in a single-drop configuration.