Connect to an externally-powered HART device

By default, the Trex unit tries to automatically connect to the device at address zero. See Automatically connect to a HART device for more information.

Remove the USB cable from the Trex unit before connecting to a device.
Note: The Trex unit acts as a secondary HART master on a HART loop.
  1. Connect the lead set to the HART terminals on the Trex unit and to the communication terminals on the device. See the HART wiring diagrams topic for the connection details.
    If you want to use the Trex internal resistor, connect the Trex unit is series with the device.
  2. Open the Field Communicator application.
    The Trex unit may automatically detect or connect to the device.
  3. If the Trex unit does not automatically connect to the device, tap HART and do the following:
    1. Tap No when asked if you want to provide power from the Trex unit.
    2. Select Transmitter or Positioner.
    3. Follow any additional prompts.
      You may see additional prompts if the Trex unit cannot connect to the device. For example, you may be prompted to review the polling address if the device is not at address zero, or to increase loop resistance. The Online menu or the device dashboard displays, depending on the device type.
    4. Tap the device displayed on the Device List.
  4. To disconnect a device, tap Menu > Disconnect, or remove the lead set.