Measure the DC voltage, noise, and the fieldbus signal

The Fieldbus Diagnostics Overview screen displays a GOOD, BAD, or CHECK status for the measurements to give you a quick summary. Check the measurement criteria in the Settings to ensure they are appropriate for your installation.

You can view the actual measurement values by tapping Details on the Fieldbus Diagnostics Overview screen.

Note: Before taking a noise measurement, remove the AC adapter from the Trex unit, if it is connected. This isolates the Trex unit from the local power grid.
  1. If the FOUNDATION fieldbus device is externally-powered, do the following:
    1. Connect the lead set to the FF terminals on the Trex unit and to the fieldbus segment or device.
    2. Open Fieldbus Diagnostics.
      The measurement status appears on the screen.
    3. If the signal measurement status is "INACTIVE" or if you want to identify the device tags that are listed on the Details screen, tap Go Online.
  2. If the FOUNDATION fieldbus device is not powered, do the following:
    1. Connect the lead set to the FF terminals on the Trex unit and directly to the communication terminals on the unpowered device. Ensure no other wires are connected to the device and there is no power to the device. Do not attach to a junction box.
    2. Connect the FOUNDATION fieldbus Power Plug to the FF pwr terminal and the positive (red) FF terminal on the lead set.
    3. Open Fieldbus Diagnostics.
    4. On the Fieldbus Diagnostics Overview screen, tap Power supply to enable power to the device. The Trex unit powers the device.
    5. If the signal measurement status is "INACTIVE" or if you want to identify the device tags that are listed on the Details screen, tap Go Online.