Emerson AMS Trex Device Communicator User Manual (English)

Questions and Answers:

S
Steven ThomasAug 13, 2025
How to troubleshoot low DC voltage on Emerson AMS Trex Device Communicator Cell Phone?
- R
  Randy RyanAug 13, 2025
  If you're seeing lower than expected DC voltage, the power supply's voltage setting might be too low. Verify the power supply's voltage setting is correct and increase it if needed. Also, a damaged cable, corrosion, low impedance to ground, water in the terminals, or loose connections could cause an unexpected voltage drop. Measure the voltage at several points on the fieldbus segment to find the location of the voltage drop, starting at the power supply.
C
Caroline HolmesAug 17, 2025
What to do if Emerson Cell Phone DC voltage is too high?
- C
  cburnettAug 17, 2025
  If the DC voltage measurement is higher than expected, it could be due to more than one voltage source on the fieldbus segment. Ensure there is only one voltage source. Also, the power supply's voltage setting may be too high. Verify that the power supply's voltage setting is correct and decrease the power supply voltage if necessary.
A
Andrea ThomasAug 21, 2025
What causes a low Fieldbus signal on an Emerson AMS Trex Device Communicator and how to fix it?
- P
  Paula MartinAug 21, 2025
  A lower than expected Fieldbus signal on your Emerson Cell Phone could be due to several reasons. First, the unit might be too far from the transmitting device; connect it directly to the communication terminals, ensuring no other wires are connected. Second, the cable between the unit and the device may be damaged; replace it if the signal loss is unacceptable. Fieldbus signals can be received when they are 250 mVp-p or higher, so loss of signal amplitude is tolerable. Third, there might be too many terminators on the fieldbus segment; review the number of terminators, as a segment should have only two.
M
Michael AndersonAug 25, 2025
Why is there high in-band frequency noise on my Emerson Cell Phone?
- D
  Diana MaxwellAug 25, 2025
  If you're getting higher than expected in-band frequency noise on your Emerson Cell Phone, it could be because the device or shield isn't properly grounded. Make sure the device is properly grounded and the shield is isolated from the terminal housing. The shield should only be grounded at one location on the entire fieldbus segment, using a high-quality ground. Also, a cable may be damaged. Visually inspect the cables and test the resistance between the two wires and each wire against the ground.
D
Dawn WilliamsAug 28, 2025
What causes high-frequency noise on Emerson AMS Trex Device Communicator Cell Phone?
- T
  Tina PattonAug 28, 2025
  If you're experiencing higher than expected high-frequency noise on your Emerson Cell Phone, it could be due to loose wire connections. Check for loose connections, as vibration from nearby motors or wind gusts may cause them. Another cause could be water or moisture in the device's terminal housing, so check the housing. Also, a cable may be damaged. Use the signal or DC voltage measurement to find the damaged cable portion, then visually inspect the cables and test the resistance between the two wires and each wire to the ground.
R
Richard HinesSep 1, 2025
How do I troubleshoot high low-frequency noise on Emerson AMS Trex Device Communicator?
- S
  Sharon MooreSep 1, 2025
  If you're experiencing higher than expected low-frequency noise on your Emerson Cell Phone, and the AC adapter is attached, disconnect it to isolate the unit from the local power grid. Also, the device or shield may not be properly grounded. Ensure the device is properly grounded and the shield is properly isolated from the terminal housing, grounded at only one location with a high-quality ground. Repeat these checks for all devices on the fieldbus segment. The power supply might not be supplying a good, stable voltage. Ensure the power supply is properly installed, isolate it, and check for noise.
C
Cindy HensonSep 5, 2025
What to do if Emerson AMS Trex Device Communicator has a high Fieldbus signal?
- C
  Crystal HillSep 5, 2025
  If the Emerson Cell Phone has a higher than expected Fieldbus signal, the unit may be attached to a block with short-circuit protection. To see the normal fieldbus signal amplitudes, connect the unit to the trunk of the connector block.
T
toddsnyderSep 9, 2025
Why doesn't my Emerson AMS Trex Device Communicator stay as the LAS on a fieldbus segment?
- G
  George FreySep 9, 2025
  When a host is established on a fieldbus segment, it will take over as the LAS. No action is required.

Emerson AMS Trex Device Communicator Specifications

General

Brand	Emerson
Model	AMS Trex Device Communicator
Category	Cell Phone
Language	English

Summary

AMS Trex Device Communicator User Guide

User Guide Overview

Overview of the AMS Trex Device Communicator User Guide's scope and purpose.

Documentation Conventions

Explains conventions used in the manual for notes, cautions, and warnings.

Technical Support

Information on how to contact technical support and what details to provide.

AMS Trex Device Communicator Overview

Trex Unit Precautions

Safety precautions and essential checks before operating the Trex unit.

Hazardous Area Operation

Information on using the Trex unit in hazardous locations.

Trex Unit Front View

Trex Unit Keypad

Details on using the keypad for navigation, selection, and text input.

Trex Unit Touchscreen

Touchscreen Gestures

Explains single-tap, press-and-hold, and scroll gestures for touchscreen interaction.

Trex Unit Back View

Trex Unit Serial Numbers

Information on viewing and locating serial numbers for the Trex unit and its parts.

Trex Unit Communication Modules

Device Communicator Module

Details on the Device Communicator module for HART and FOUNDATION fieldbus.

Device Communicator Plus Module

Details on the Device Communicator Plus module for HART and FOUNDATION fieldbus.

Device Communicator Plus Ammeter Functions

Install Communication Module

Remove Communication Module

Trex Unit Power Module

Power Module and AC Adapter Precautions

Safety and handling precautions for the power module and AC adapter.

Trex Unit AC Adapter

Power Module LEDs

View Remaining Power Module Charge

Charge the Power Module

Install Power Module into Trex Unit

Remove Power Module from Trex Unit

Maintain the Power Module

Trex Unit Accessories

Cables and Lead Sets

Details on the lead set and FOUNDATION fieldbus Power Plug for connecting devices.

Trex Unit Carrying Case

Powering the Trex Unit On or Off

Rebooting the Trex Unit

Procedure for rebooting the Trex unit via the Settings menu.

Trex Unit Hard Shutdown

Trex Unit Home Screen

Return to Home Screen

Instructions on how to return to the Home screen from an open application.

Trex Unit Status Bar

Information displayed on the status bar, including time, icons, and pull-down tab.

Trex Unit Shortcut Bar

Trex Unit Settings

View All Open Applications

Procedure to view all currently open applications on the Trex unit.

Close an Application

Procedure to close an application using the Exit button or Settings menu.

Change Screen Brightness

Trex Unit Wireless Communication

Connect to Broadcasting Wireless Network

Procedure to connect the Trex unit to a broadcasting wireless network.

Connect to Non-Broadcasting Wireless Network

Procedure to connect the Trex unit to a non-broadcasting wireless network manually.

Enter Network Address for AMS Trex Unit

Forget Wireless Network

Procedure to prevent the Trex unit from automatically reconnecting to a wireless network.

View Trex Hardware and Operating System Info

Name the Trex Unit

Procedure for assigning a unique name to the Trex unit for identification.

View Application Version Numbers

How to view version numbers for all installed applications on the Trex unit.

Set Trex Unit Time and Date

Instructions for setting the time and date, including automatic updates via network.

Calibrate Trex Unit Touchscreen

Set Trex Unit Language

Procedure for changing the display language, which requires a reboot.

Trex Unit Power Management

View Available Memory

How to view the amount of available memory on the Trex unit.

Enter or Exit Suspend Mode

How to put the Trex unit into or out of suspend mode for power saving.

Set Backlight Timer

Set Suspend Timer

Set Shut Down Timer

Auto-Connect to HART Devices

Enable Diagnostic Logging

Trex Unit Applications

Activating the Trex Unit

Recommended procedure to activate the Trex unit using Upgrade Studio.

Close Trex Unit Application

Procedure to close an application from the Trex unit.

Trex Unit USB Communication

Synchronize AMS Trex Data with AMS Device Manager

Sync Trex Data to Device Manager via USB

Procedure for synchronizing data using a USB connection.

Pair Trex Unit with AMS Device Manager

Procedure to pair the Trex unit with an AMS Device Manager station.

Unpair AMS Trex Unit

Upgrade Studio Software

Connect Trex Unit to Upgrade Studio via USB

Create Trex Online User Account

Activate the Trex Unit

Activate Trex Unit Without Internet

Procedure for activating the Trex unit using an activation code obtained via email or phone.

AMS Trex Security Management

Initial Security Setup

Initial setup of security schemes (Local or Enterprise) for the Trex unit.

Local Security Configuration

Enabling and managing local user accounts for Trex unit access.

Enterprise Security Configuration

Enabling enterprise security using Windows domain credentials.

Enable Local Security

Enable Enterprise Security

Disable Trex Unit Security

Create Local User Account

Delete Local User Account

Reset Local User Password

Pair NFC Card to User

Remove Paired NFC Card

Transfer Files to PC

Trex Unit Maintenance and Repair

Replace the Trex Unit Stand

Procedure for removing and replacing the stand on the Trex unit.

Trex Unit Calibration

Field Communicator Application

Open or Close Field Communicator Application

Procedure for opening and closing the Field Communicator application.

Field Communicator Device Interoperability

Forward Compatibility for Configurations

Automatically Detect a Device

Auto-Connect to HART Device

Field Communicator Connect-Select Screen

Field Communicator Device Connection Wizard

Device Detection Status Messages

Online Menu or Device Dashboard

Field Communicator Online Menu

Options typically found in the Online menu for device parameters.

Field Communicator Dashboard Menu

Options found in the Dashboard menu, including Overview, Service Tools, and Configure.

Device Screen Layout

Device Screen Status Bar

Functionality of the status bar for accessing settings and switching applications.

Device Screen Application Title Bar

Information on the application title bar, including device tag and menu title.

Device Screen Application Bar

Field Communicator Menu Screen

Device Menu Icons

Connecting to HART Devices

HART Communication Terminals

Details on HART terminals for communication and connection requirements.

HART Device Wiring Diagrams

Smart Wireless THUM Adapter Wiring Diagrams

HART Device List

Trex Unit Internal Resistors

Connections to Externally-Powered Transmitters

How to use internal resistors for externally-powered transmitters.

Enable or Disable Internal Resistors

Power and Connect to HART Device

Power and Connect to Smart Wireless THUM Adapter

Connect to Externally-Powered HART Device

Online HART Devices

HART Device Communication Icons

Icons in the status bar indicating HART device communication status.

Device Setup Options

Device Setup Process Variables

Viewing process variables and their continuously updated values.

Device Setup Diagnostics and Service

Performing device and loop tests, and calibration options.

Device Setup Basic Setup

Fundamental tasks like modifying tag, units, damping, and range values.

Device Setup Detailed Setup

Accessing all editable parameters and device functions.

Change Device Parameters

Change HART Device Parameter

Modifying one or more parameters and sending the changes to the HART device.

Edit HART Configuration

Display HART Short or Long Tag

View Device Alerts

Send Configuration to Connected HART Device

Save Configuration from HART Device

Offline HART Configurations

Create HART Configuration

Creating a new HART configuration for specific device types and revisions.

Edit HART Configuration

Editing an existing HART configuration offline.

Copy HART Configuration

Rename HART Configuration

Delete HART Configuration

HART Device Favorites

Open Favorites Menu Item

Opening a menu item from the favorites list for HART devices.

Add Menu Item to Favorites

Adding menu items to the favorites list for quick access.

Remove Favorite Menu Item

HART Device Polling Options

Set HART Device Polling Options

Procedure for setting polling options like address, tag, or long tag.

Connecting to FOUNDATION Fieldbus Devices

FOUNDATION Fieldbus Device Precautions

Safety precautions when using the Trex unit with FOUNDATION fieldbus devices.

FOUNDATION Fieldbus Communication Terminals

FOUNDATION Fieldbus Wiring Diagrams

FOUNDATION Fieldbus Link Active Scheduler (LAS)

FOUNDATION Fieldbus Device List

Power and Connect to FOUNDATION Fieldbus Device

Connect to Externally-Powered Fieldbus Segment

Online FOUNDATION Fieldbus Devices

Commissioned Device Limitations

Tasks that cannot be completed on commissioned devices to prevent process disruption.

FOUNDATION Fieldbus Device Blocks

Organization of device parameters into blocks and their operational modes.

Change FOUNDATION Fieldbus Block Mode

Change IO Block Schedule for FOUNDATION Fieldbus

View Block Status

Run Method on FOUNDATION Fieldbus Device

View FOUNDATION Fieldbus Device Information

Change FOUNDATION Fieldbus Device Parameter

Change FOUNDATION Fieldbus Device Tag

Guidelines for Changing FOUNDATION Fieldbus Device Address

Change FOUNDATION Fieldbus Device Address

Polling FOUNDATION Fieldbus Devices

Set FOUNDATION Fieldbus Device as Link Master or Basic

Simulate Live Device

View Device Descriptions on Trex Unit

View Device Description Information

View Help for Device Parameter

Device Graphics Display

Strip/Sweep/Scope Chart

Displays device data over time in a line chart format.

Horizontal Bar Charts

Formats device data into bars from left to right, varying with time.

Vertical Bar Charts

Formats device data into bars from bottom to top, varying with time.

Gauge Charts

Formats device data into a speedometer-like view, plotting data varying with time.

Device Information Graphs

Snapshot line drawings of device information, allowing zoom and variable selection.

Disconnecting a Device

Loop Diagnostics Application

Open or Close Loop Diagnostics Application

Procedure for opening and closing the Loop Diagnostics application.

Loop Diagnostics Screen Overview

View Connection Diagram Full Screen

Power Transmitters or Positioners with Loop Diagnostics

Power a Transmitter with Loop Diagnostics

Procedure for powering a transmitter using the Trex unit.

Power a Positioner with Loop Diagnostics

Procedure for powering a positioner and controlling current.

Simulate Transmitter with 4 mA

Disable Power to Device

Voltage and Current Measurements in Loop Diagnostics

Loop Diagnostics Wiring Diagrams

Power a 2-Wire Transmitter

Power 2-Wire Transmitter and Measure Analog Output

Power a Positioner

Stroke a Valve

Current Control Settings

Change Quick Button Values

Customizing values for the quick current buttons on the Loop Diagnostics screen.

Change Scale for Arrow Keys

Set Duration for Current Change

Loop Checks

Measure Voltage on Externally-Powered Loop

Measure Control System Output

Simulate Transmitter on Externally-Powered Loop

Simulate Transmitter on Unpowered Loop

Fieldbus Diagnostics Application

Fieldbus Diagnostics Measurements

Details on measuring DC voltage, noise, and fieldbus signal levels.

Quick Ad-Hoc Network Tests

Using Trex unit to connect to points on fieldbus segment to isolate issues.

Long-Term Tests for Sporadic Issues

Taking measurements over time to capture sporadic issues like noise.

Periodic Tests for Network Tracking

Taking measurements periodically to track network trends and degradation.

Open or Close Fieldbus Diagnostics Application

Fieldbus Diagnostics Overview Screen

DC Voltage Status

View the status of the DC voltage measurement.

Noise Measurement Status

View the status of the noise measurements.

Noise Spectrum Analysis

View a spectrum of the low-frequency, in-band, and high-frequency noise measurements.

Measurement Display and Collection Settings

Set options for displaying and collecting the measurements.

View Measurement Values

View the values for each measurement.

Log Measurements to File

Enable or disable saving the measurements to a log file (.csv,), and set the logging settings.

Power FOUNDATION Fieldbus Device

Enable or disable power to a FOUNDATION fieldbus device.

Fieldbus Signal Status

View the status of the fieldbus signal measurement.

Go Online/Offline Functionality

Tap Go Online or Go Offline to have the Trex unit go online or offline.

GOOD, BAD, CHECK Status in Fieldbus Diagnostics

Fieldbus Diagnostics Wiring Diagrams

Power FOUNDATION Fieldbus Device

Connect to Externally-Powered Fieldbus Segment

Measure Fieldbus DC Voltage, Noise, and Signal

Fieldbus Diagnostics Details Screen

View Live Fieldbus Measurements

View Help for Fieldbus Measurement

Fieldbus Noise Spectrum Analysis

How Noise Affects Fieldbus Segment

View Noise Measurement Spectrum

Fieldbus Diagnostics Settings

Show/Hide Min, Max, Avg Values

Configuring the display of min, max, and average values on the Details screen.

Show/Hide Device Tags Online

Configuring the display of host and device tags when the Trex unit is online.

Set Number of Measurements to Average

Setting the number of measurements to average for DC voltage, noise, and signal.

Set GOOD/BAD Status Value Ranges

Reset Fieldbus Diagnostics Settings

Save Measurements to Log File

Creating Trends and Reports

Fieldbus Diagnostics Log File Overview

Log File Measurement Intervals

View Saved Measurements on PC

Enable or Disable Logging

Save Measurements to Existing Log File

Transfer Fieldbus Log File to PC

Troubleshooting Fieldbus Diagnostics

Troubleshooting

Troubleshoot HART Communication

Symptom/cause/solution guide for HART communication issues.

HART Loop Verification

Troubleshoot Fieldbus Communication

Technical Specifications

Physical Specifications

Specifications for the hardware, including weight, dimensions, display, and buttons.

Communication Module Specifications

Specifications for Device Communicator and Plus modules, including terminals and fuses.

Processor, Memory, OS Specifications

Environmental Specifications

Intrinsically Safe Electrical Parameters

Power Module Specifications

AC Adapter Specifications

Product Certifications

Wireless/Spectrum Approvals

Glossary

Index

Related product manuals

Emerson AMS Trex Device Communicator User Manual

Table of Contents