Wiring diagrams for the Smart Wireless THUM™ Adapter and the Field Communicator application

Below each diagram, a table lists the expected prompts from the device connection wizard and the answers to select to complete the connection.

If you are using a WirelessHART adapter that is not the Smart Wireless THUM adapter, review its documentation before connecting the Trex unit.

Note:
  • Ensure you review the documentation included with the THUM adapter for additional information.
  • The Trex unit acts as a secondary HART master on a HART loop.
CAUTION:
Remove the USB cable from the Trex unit before connecting to a device.

Power the THUM adapter without a device attached and use 250 Ohm resistor

Connect the lead set to the red and black wires.

Device connection wizard prompts Answer
Do you intend to provide power from the Trex unit? Yes
Are you providing power to a transmitter or positioner? Positioner

Select Positioner because the Trex unit needs to control/limit current due to the lower value of the resistor.

Change Polling Option? Tap Yes and select the address for the THUM adapter.

Power and communicate with the THUM adapter attached to a HART transmitter

Note: If you want to communicate with the THUM adapter rather than the device, ensure the Auto-Connect option for the Field Communicator Settings is disabled. This allows the Field Communicator application to detect both the THUM adapter and the transmitter, and let you select which one to communicate with.
Device connection wizard prompts Answer
Do you intend to provide power from the Trex unit? Yes
Are you providing power to a transmitter or positioner? Transmitter
Change Polling Option? Tap Yes and select the address for the THUM adapter, the device, or "0,63" for both.

Communicate with the THUM adapter attached to a powered HART transmitter

Connect the lead set to the yellow and white wires.

Note: If you want to communicate with the THUM adapter, ensure the Auto-Connect option for the Field Communicator Settings is disabled. This allows the Field Communicator application to detect both the THUM adapter and the transmitter, and let you select which one to communicate with.
  1. Optional connection if the yellow and white wires are inaccessible.
  2. Voltage source.
Device connection wizard prompts Answer
Do you intend to provide power from the Trex unit? No
Leads are attached to: Transmitter
Change Polling Option? Tap Yes and select the address for the THUM adapter, the device, or "0,63" for both.

Communicate with the THUM adapter powered by a voltage source

Connect the lead set to the yellow and white/black wires.

  1. Voltage source.
Device connection wizard prompts Answer
Do you intend to provide power from the Trex unit? No
Leads are attached to: Transmitter
Change Polling Option? Tap Yes and select 63.

Communicate with the THUM adapter powered by a current source

Connect the lead set to the yellow and white/black wires. The 250 Ohm resistor is not required, but it may be used to verify current.

  1. Current source.
Device connection wizard prompts Answer
Do you intend to provide power from the Trex unit? No
Leads are attached to: Positioner
Change Polling Option? Tap Yes and select 63.