Emerson Rosemount 3814 - Page 52

Table 3-4: Serial Port A parameters
Port/Communication Description Common features
Port A (Standard)
• RS-232
• RS-485 Half Duplex
• RS-485 Full Duplex
• Typically used for
general communications
with a flow computer,
RTU (Modbus slave) and
radios.
• Special override mode to
force port configuration
to known settings.
• Supports RTS/CTS
handshaking with
software-configurable
RTS on/off delay times.
• Factory default is RS-232,
Address 32, 19200 baud.
Communications via
MeterLink using RS-232 or
RS-485 Full Duplex
• Software configurable
Modbus Address (1-247)
• Auto-detects TCP/IP and
ASCII or RTU Protocol
— ASCII Protocol: Start
Bits = 1, Data Bits=7
(1)
— Parity: odd or even 1,
Stop Bits = 1
(1)
— Baud Rates: 1200,
2400, 9600, 19200,
38400, 57600, 115000
bps
— RTU Protocol: Start
Bits = 1, Data Bits =
8
(1)
— Parity: none, Stop Bits
= 1
(1)
— Baud Rates: 1200,
2400, 9600,19200,
38400, 57600, 115000
bps
Ethernet • Preferred port for
diagnostic
communication via
MeterLink
• 10 Mbps/100 Mbps
• Modbus TCP/IP
(1) Denotes auto-detected protocols.
NOTICE
If not using Ethernet, a full duplex serial connection is necessary for MeterLink to
communicate with a Rosemount 3814 Liquid Ultrasonic Meter.
Electrical Installation Installation manual
January 2023 00825-0100-3814
52 Emerson.com/Rosemount