Emerson 5400, 5300 specifications Modbus RTU Parameter Configuration Example

Rosemount 5300/5400 Series

Manual Supplement

00809-0500-4530, Rev AA October 2010

Using a Field Communicator to change communication parameters

Modbus RTU Communication Setup

Table 1-4. Modbus RTU Communication Parameters

NOTE

To change Modbus communication parameters, the Rosemount 5300/5400 must use HART address 1, the default address.

NOTE

After changing communication parameters, disconnect the Field Communicator and wait up to 60 seconds for the change to take effect.

The Modbus communication parameters can be changed by entering a text string in the HART Message parameter. See separate sections below for details regarding each Modbus protocol and what strings to use.

When using the Field Communicator, the Message Area is reached using HART command [2,2,1], and then selecting Message (menu item 11 for Rosemount 5300 and menu item 10 for Rosemount 5400).

The Rosemount 5300/5400 is configured with the default Modbus RTU address 246, and with the following Modbus RTU communication parameter default settings:

Parameter	Default Value	Configurable Values
Baud Rate	9600	1200, 2400, 4800, 9600, 19200
Start Bits(1)	One	One
Data Bits(1)	Eight	Eight
Parity	None	None, Odd, Even
Stop Bits	One	One or Two
Address	246	1-255
range

(1) Start Bits and Data Bits cannot be changed.

Table 1-5. Communication Parameters Used by the Host (example)

To reset the communication parameters to default Modbus RTU settings, use the following Modbus Message:

HMC

Modbus RTU Parameter Configuration Example

You want to use address 44 for the 5300/5400 transmitter, and the following communication parameters are used by the host:

Parameter	Value
Baud Rate	4800
Start Bits	One
Data Bits	Eight
Parity	Odd
Stop Bits	Two

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