Emerson Micro Motion 2500, Configuration And Use Manual

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Important
You must trim the output at both ends (4 mA and 20 mA to ensure that it is compensated accurately
across the entire output range.
Prerequisites
Ensure that the mA output is wired to the receiving device that will be used in production.
Procedure
1. Follow the instructions in the guided method.
2. Choose .
3. Check the trim results. If any trim result is less than − 20 microamps or greater than
+20 microamps, contact customer service.
12.16 Check the HART communication loop
If you cannot establish or maintain HART communications, the HART loop may be wired
incorrectly.
Prerequisites
You will need:
• A copy of your transmitter installation manual
• A 250–600 Ω resistor
• A Field Communicator
• Optional: the HART Application Guide , available at www.hartcomm.org
Procedure
1. Verify that the loop wires are connected as shown in the wiring diagrams in the
transmitter installation manual.
If your HART network is more complex than the wiring diagrams in the transmitter
installation manual, contact either customer service or the HART Communication
Foundation.
2. Disconnect the primary mA Output wiring from the transmitter.
3. Install a 250–600 Ω resistor across the transmitter’s primary mA Output terminals.
4. Check the voltage drop across the resistor (4–20 mA = 1–5 VDC for a 250 Ω
resistor).
If voltage drop is less than 1 VDC, add resistance to achieve a voltage drop of greater
than 1 VDC .
5. Connect a Field Communicator directly across the resistor and attempt to
communicate (poll).
Troubleshooting
184 Micro Motion Model 2500 Transmitters with Configurable Input/Outputs