Emerson Micro Motion LNG Series, Configuration And Use Manual

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6.2.1 Configure Modbus/RS-485 communications
ProLink III Device Tools > Configuration > Communications > Communications (Modbus)
Overview
Modbus/RS-485 communications parameters control Modbus communication with the
transmitter's RS-485 terminals.
Modbus/RS-485 communications parameters include:
•
Modbus Address
(
Slave Address
)
•
Floating-Point Byte Order
•
Additional Communications Response Delay
Procedure
1. Set Modbus Address to a unique value on the network.
2. Set Floating-Point Byte Order to match the byte order used by your Modbus host.
Code Byte order
0 1–2 3–4
1 3–4 1–2
2 2–1 4–3
3 4–3 2–1
See Table 6‐2 for the bit structure of bytes 1, 2, 3, and 4.
Bit structure of floating-point bytes Table 6-2:
Byte Bits Definition
1 SEEEEEEE S=Sign
E=Exponent
2 EMMMMMMM E=Exponent
M=Mantissa
3 MMMMMMMM M=Mantissa
4 MMMMMMMM M=Mantissa
3. (Optional) Set
Additional Communications Response Delay
in delay units.
A delay unit is 2/3 of the time required to transmit one character, as calculated for
the port currently in use and the character transmission parameters. Valid values
range from 1 to 255.
Integrate the meter with the control system
Configuration and Use Manual 47