Emerson Micro Motion 2500, Configuration And Use Manual

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6. Set the connection parameters to the values configured in the transmitter.
If your transmitter has not been configured, use the default values shown here.
Default Modbus/RS-485 connection parameters Table A-1:
Parameter Default value
Protocol Modbus RTU
Baud
9600
Parity Odd
Stop Bits
1
Address
1
Tip
If you do not know the transmitter’s RS-485 communication settings, you can connect
through the service port, which always uses default settings, or use another communications
tool to view or change the settings.
7. Set the PC Port value to the PC COM port that you are using for this connection.
8. If required, power-cycle the transmitter and wait 10 seconds to set the terminals to
RS-485 mode.
The transmitter terminals operate in either service port mode or RS-485 mode. If
they are in service port mode, you must power-cycle the transmitter and wait for
10 seconds before connecting. At the end of this period, the terminals switch to
RS-485 mode. If the terminals are already in RS-485 mode, skip this step.
9. Select Connect.
Need help? If an error message appears:
• Verify the Modbus address of the transmitter.
• Ensure that you have specified the correct port on your PC.
• Ensure that the RS-485 terminals on the transmitter are in RS-485 mode.
• Check the wiring between the PC and the transmitter.
• Increase or decrease resistance.
• For long-distance communication, or if noise from an external source interferes with the
signal, install 120-
Ω
½
-W terminating resistors in parallel with the output at both ends of
the communication segment.
• Ensure that there is no concurrent Modbus communication to the transmitter.
Using ProLink III with the transmitter
Configuration and Use Manual 207