Fox Thermal Model FT4X Thermal Mass Flow Meter

Model FT4X flow meter

FT4X Flow Meter
The Fox Thermal Model FT4X, is the most fully-featured Thermal Gas Mass Flow Meter offered from Fox Thermal.

Its advanced Data Logger has a 7-year history!

Key Features:

  • Insertion, Inline & Remote Styles
  • DC or AC power options
  • DDC-Sensor™ Technology
  • Gas-SelectX® & CAL-V™
  • Advanced Data Logger
  • FC20 Flow Conditioner option
  • Scroll down for more features/benefits!

ModbusView™ Software
ModbusView™ is Fox Thermal software for FT4X meters equipped with the Modbus RTU (RS485) communication option. It provides a streamlined way to connect to compatible FT4X meters through the Modbus interface, access meter information, and support commissioning and ongoing monitoring. Use ModbusView™ to:

  • Connect to compatible FT4X meters through Modbus RTU (RS485)
  • View available process and meter information
  • Access supported configuration and diagnostic functions
  • Support commissioning, troubleshooting, and field service workflows

Connection: Modbus RTU (RS485)
Compatibility: FT4X configured with the Modbus RTU communication option
Availability: Free download (see "Downloads")

FT4X View™ Software
The free FT4X View™ software from Fox Thermal is a great way to connect to the Model FT4X from a PC or laptop to access the meter settings in a quick and visually appealing way. This software offers:

  • Quick access to all configuration parameters using pop-up windows and pull down menus
  • Selection of measurement units, flow and temperature ranges, alarm settings, and more
  • Gas-SelectX® Gas Selection Menu
  • CAL-V™ Calibration Validation Certificate
  • View Logs for 40 24-hour daily totals and events/alarms
  • Data collection to a Microsoft® Excel spreadsheet
  • Display of alarm codes
  • Storage of meter configurations to a file that can be archived
  • View raw data that can be used to diagnose or troubleshoot your meter

Calibration Validation
The CAL-V™ test is used for Calibration Validation on the Model FT4X. This test does the following:

  • Tests the functionality of the sensor and its associated signal processing circuitry
  • Checks for build-up on sensor that could affect calibration
  • Ensures that the meter still retains its original NIST-traceable calibration

Use this test according to the manufacturer’s instructions in order to validate the calibration of the meter.

Gas-SelectX® Multi-Gas Flexibility
Gas-SelectX® allows FT4X users to select a pure gas or configure a custom gas mixture in the field. Powered by Fox Thermal’s DDC‑Sensor™ technology and advanced correlation algorithms, the feature gives operators flexibility to adapt the meter to changing process requirements without changing hardware.

Available gases
Methane, Carbon Dioxide, Nitrogen, Helium, Argon, Hydrogen, Air, Propane, Butane, Oxygen, Ethane, Iso Butane, Pentane, Hexane, Heptane, Octane, Nonane, Ethylene, Propylene, Ammonia, Chlorine, Carbon Monoxide, Decane, Ethanol, Hydrogen Sulfide, Iso Pentane, Methanol, Nitrous Oxide, Pentafluoroethane, Tetrafluoroethane, Trifluoroethane, Chlorodifluoromethane, Difluoromethane, Sulfur Hexafluoride, Sulfur Dioxide, Water, Acetone, Propadiene, 1-Butyne, Benzene, and Ozone.

Custom gas mixtures
Create a custom gas mixture using any combination of the available gases in the Gas Mix or Oil & Gas menus. Gas composition is programmable in 0.000001% increments, giving users exceptional flexibility to configure the FT4X for their application. The Gas-SelectX® feature can be accessed through the front panel of the meter or by using Fox Thermal's ModbusView™ software or FT4X View™ software.

Standard Data Logger with Date/Time Stamp

Every Fox Thermal Model FT4X includes an intrinsic Data Logger for reliable data retention and record-keeping. Common applications include flare gas monitoring, gas studies, allocation, royalties, and flow research.

The Data Logger is easily activated through the meter's front panel keypad during setup. Once the date and local time are configured, it records flow totals, events, and alarms with time and date stamps.

Key Data Logger features include:

  • 40 daily (24-hour) totals
  • Settable Contract Time to define the Contract Day
  • Time/date stamped alarm & event logs; 7 year history
  • Power off totalizer; power failure creates event log entry

The Data Logger also provides access to:

  • Gas or gas mix composition data
  • Meter configuration and settings
  • Calibration Validation test history
  • Event and alarm logs for viewing or printing

Logs can be accessed via the MODBUS RTU (RS485) communication option, ModbusView™ software, and FT4X View™ software.

Flow Conditioners
Flow meter accuracy is often dependent on achieving a uniform flow profile near the center of the pipe. Distortion and swirl are disturbances in flow that can be remedied either by extending the length of space between the cause of the disturbance and the sensing element (increasing straight pipe runs) or by adding a flow conditioner to correct the disturbance. Flow conditioners installed upstream of flow meters reduce the need for long, straight pipe runs. Common Features for Fox Thermal FC20 Flow Conditioner:

  • For use with all Fox insertion style flow meters
  • Reduces the need for long straight pipe runs
  • Negigible pressure drop
  • Precision, laser-cut design
  • 316 stainless steel material

More Info

Common Features for Fox Thermal Model FT4X Flow Meter:

  • Measures process gas flow rate/total and temperature
  • Insertion probes (for 1.5" - 70" pipes); Inline flow bodies with NPT ends (3/4" - 3" pipes); Inline 150# & 300# Flanged flow bodies (3/4" - 6" pipes)
  • Equipped with the DDC-Sensor™ (Direct Digitally Controlled)
  • 3/4-inch (standard) and 1/2-inch (optional) probe diameters
  • Gas-SelectX® expanded gas selection menu. Choose from available list of gases/gas mixes to measure flow. NIST-traceable calibration
  • Advanced Data Logger with Real Time Clock and 40 24-Hour daily totals
  • Settable Contract Time defines Contract Day
  • A USB connection is standard (free FT4X View™ Software); Optional HART and Modbus RTU (RS485) communication protocols
  • ModbusView™ software for Modbus-equipped FT4X configurations
  • Standard on-board display and configuration panel
  • Two standard isolated 4-20mA outputs: Channel 1 configured to indicate flow, fault indication per NAMUR NE43. HART communication option; Channel 2 configured to indicate either flow or temperature
  • One isolated open collector output for pulse/alarm
  • One switch input to reset total
  • Click the Approvals tab for Model FT4X Agency Approval details
  • Calibration Validation with the CAL-V™ test
  • NIST-traceable calibration
  • Wide measurement range
  • Flow Accuracy for air: ±1% R ±0.2% FS; Flow accuracy for other gases: ±1.5% R ±0.5% FS
  • 24 VDC or optional 100 to 240VAC in local or remote enclosures
  • FC20 Flow Conditioner ordering option to reduce straight run requirements for insertion style flow meters

FT4X Flow Meter Specs

Technical Specifications
Fox Thermal Model FT4X Thermal Mass Flow Meter & Temperature Transmitter
Performance Specs
Type
Insertion
Inline
Flow Accuracy:
Air: ± 1% of reading ± 0.2% of full scale.
Other Gases: ± 1.5% of reading ± 0.5% of full scale.
Accuracy specification applies to customer's selected flow range
Straight, unobstructed pipe requirement:
15 diameters upstream; 10 downstream.

5 diameters upstream; 5 downstream of FT4X (with FC20 flow conditioners)
8 diameters upstream; 4 downstream.
 
 
 
Flow Repeatability:
± 0.2% of full scale
Flow Response Time:
0.8 seconds (one time constant)
Temperature Accuracy:
± 1° F (± 0.6° C)
Calibration:
Factory Calibration to NIST-traceable standards
CAL-V™: In situ, operator-initiated calibration validation
Operating Specs
Type
Insertion
Inline
Flow Units (field selectable):
SCFM, SCFH, NM3/M, NM3/H, NM3/D, NLPS, NLPM, NLPH, MCFD, MSCFD, SCFD, MMSCFD, MMSCFM, SM3/M, SM3/D, SM3/H, LBS/S, LBS/M, LBS/H, LBS/D, KG/S, KG/M, KG/H, SLPM, MT/H
Flow Rates:
Maximum range: 15 to 60,000 SFPM (0.07 to 280 NMPS)
Minimum range: 15 to 500 SFPM (0.07 to 2.4 NMPS)
Turndown:
up to 1000:1; 100:1 typical
Flow Ranges:
Pipe Size SCFM MSCFD NM³/HR
1.5" (40mm) 0 - 840 0 - 1,220 0 - 1,325
2" (50mm) 0 - 1,400 0 - 2,020 0 - 2,210
2.5" (63mm) 0 - 2,000 0 - 2,880 0 - 3,150
3" (80mm) 0 - 3,100 0 - 4,440 0 - 4,890
4" (100mm) 0 - 5,300 0 - 7,650 0 - 8,360
6" (150mm) 0 - 12,000 0 - 17,340 0 - 18,930
8" (200mm) 0 - 20,840 0 - 30,020 0 - 32,870
10" (250mm) 0 - 32,800 0 - 47,250 0 - 51,740
12" (300mm) 0 - 46,600 0 - 67,180 0 - 73,500
Pipe Diameter SCFM MSCFD NM³/HR
0.75" (20mm) 0 - 220 0 - 320 0 - 350
1" (25mm) 0 - 360 0 - 520 0 - 570
1.25" (32mm) 0 - 625 0 - 900 0 - 990
1.5" (40mm) 0 - 840 0 - 1,220 0 - 1,325
2" (50mm) 0 - 1,400 0 - 2,020 0 - 2,210
2.5" (63mm) 0 - 2,000 0 - 2,880 0 - 3,150
3" (80mm) 0 - 3,100 0 - 4,440 0 - 4,890
4" (100mm) 0 - 5,300 0 - 7,650 0 - 8,360
6" (150mm) 0 - 12,000 0 - 17,340 0 - 18,930
Note: To determine if the FT4X will operate accurately in other pipe sizes, divide maximum flow rate by the pipe area. The application is acceptable if the resulting velocity is within the velocity range above.
Note: Consult factory for flow ranges above those listed. Inline meters above 5,000 SCFM (7,900 NM3/H) air may require third party calibration.
Gas Pressure (max):
w/o Retractor: 740 psig (51.02 barg)
with Retractor: 150 psig (10.3 barg)
 
 
316 SS inline w/NPT ends: 500 psig (34.5 barg)
316 SS inline w/150lb flanges: 230 psig (16 barg)
316 SS inline w/300lb flanges: 600 psig (41 barg)
CS inline w/NPT ends: 500 psig (34.5 barg)
CS inline w/150lb flanges: 285 psig (20 barg)
CS inline w/300lb flanges: 740 psig (51 barg)
Check with factory for higher pressure options.
NOTE: When teflon ferrule option ordered, gas pressure is 60psig (4.1 barg) maximum.
Relative Humidity:
90% RH maximum; non-condensing
NOTE: Condensing liquids contacting the sensor can cause erratic flow indication.
Temperature:
DDC-Sensor™: -40 to 250°F (-40 to 121°C)
Enclosure: -40 to 158°F (-40 to 70°C)
Remote Sensor Enclosure: -40 to 158°F (-40 to 70°C)
Note: Display dims below -4°F (-20°C); function returns once temperature rises again.
Input Power:
12 to 24 VDCDC Power, 6 Watts. Full input power input range: 10 to 30VDC (standard DC power).
A 20 Watt or greater DC power supply is recommended to power the FT4X.
100 to 240VACAC Power, 50-60Hz, 7 Watts. Full input power range: 85 to 264VAC (AC power option).
Inputs/Outputs
4-20mA Channel 1:
  • Standard isolated 4-20mA output configured to indicate for flow; fault indication per NAMUR NE43. HART communication option.
  • The 4-20mA load resistance must be 125 ohms or less when operating on 12 volt power and 600 ohms or less on 24 volt power.
4-20mA Channel 2:
  • Standard isolated 4-20mA output configured to indicate either flow or temperature.
Pulse/Alarm:
  • Isolated open collector output rated for 5 to 24VDC, 20mA maximum load, 0 to 100Hz (the pulse output can be configured to either transmit a 0 to 100Hz signal proportional to flow rate or an on/off alarm).
Remote Switch Input:
  • Can be configured to reset the flow totalizer and elapsed time.
Port:
Micro USB communication port is standard.
Software:
The free PC-based software tool - FT4X View™ - provides complete configuration, remote process monitoring, and data logging functions.
Optional serial communication:
HART or Modbus RTU (RS485).
4-20mA and Pulse Verification:
Simulation mode used to align 4-20mA output and pulse output (if ordered) with the input to customer’s PLC/DCS.
Physical Specs
Type
Insertion
Inline
Sensor Material:
316 stainless steel standard.
Probe Diameter:
3/4” probe diameter standard with 1” MNPT compression fitting (3/4” fitting optional). 1/2” probe diameter optional with 3/4” compression fitting.
Enclosure:
NEMA 4X (IP67), aluminum, dual conduit entries with ¾" FNPT conduit entries.
Cabling to remote enclosure: 8-conductor, 18 AWG, twisted, shielded, 100 feet maximum.
Retractor Assemblies:
150 psig (10.3 barg) max.
 
N/A
Installation:
Fox Thermal-supplied compression fitting connects to customer-supplied 1" female coupling welded to pipe.
Compression fitting included with flow body.

FT4X Approvals

CE: Approved

  • EMC Directive; 2014/30/EU
  • Electrical Equipment for Measurement, Control and Lab Use: EN61326-1:2013
  • Low Voltage Directive (LVD): 2014/35/EU
  • Product Safety Testing: EN 61010-1: 2010
  • Pressure Equipment Directive: 2014/68/EU Article 13
  • Weld Testing: EN ISO 15614-1 and EN ISO 9606-1, ASME B31.3

FM (FM17US0061X) and FMc (FM17CA0032X): Approved

  • Class I, Division 1, Groups B, C, D;
  • Class II, Division 1, Groups E, F, G;
  • Class III, Division 1; T6 or T4, Ta = -40°C to 70°C;
  • Class I, Zone 1, AEx/Ex db IIB+H2 T6 or T4; Gb Ta = -20°C to 70°C; Type 4X, IP67

ATEX (FM17ATEX0015X): Approved

  • II 2 G Ex db IIB+H2 T6 or T4; Gb Ta = -20°C to 70°C; IP67
  • II 2 D Ex tb IIIC T85°C or T135°C; Db Ta = -20°C to 70°C; IP67

IECEx (IECEx FMG 17.0008X): Approved

  • Ex db IIB+H2 T6 or T4; Gb Ta = -20°C to 70°C; IP67
  • Ex tb IIIC T85°C or T135°C; Db Ta = -20°C to 70°C; IP67

UKEX (FM21UKEX0170X): Approved

  • II 2 G Ex db IIB+H2 T6 or T4; Gb Ta = -20°C to 70°C; IP67
  • II 2 D Ex tb IIIC T85°C or T135°C; Db Ta = -20°C to 70°C; IP67

ATEX and IECEx Standards:

EN 60079-0 + A11
EN 60079-1
EN 60079-31
EN 60529 + A1

IEC 60079-0
IEC 60079-1
IEC 60079-31
IEC 60529

Optional items available for the Model FT4X Flow Meter:

Talk with our application specialist or a rep near you for sizing and materials requirements

  • FC20 Flow Conditioner for use with insertion style FT4X
  • ModbusView™ software license for remote connectivity
  • USB remote connectivity kit (ModbusView RS485-to-USB converter)
  • RJ45 remote connectivity kit (ModbusView RS485-to-RJ45 converter)
  • AC to 24VDC power converter with DIN mounting rail
  • Flow meter cleaned and bagged for Oxygen service
  • Certificate of Conformance
  • Certificate of Origin
  • Material certificate for wetted parts
  • Extra Instruction Manual
  • M20x1.5 wiring connection adapters (qty. 2 per meter)
  • USB Cable, A-male/mini USB-B male, 6' length
  • Teflon Ferrule Kits (for 3/4" or 1/2" probe sizes), 60 psi max. pressure
  • 3/4" MNPT compression fitting for probe process connection with 3/4" probe diameter
  • 1/2" MNPT compression fitting for probe process connection with 1/2" probe diameter
  • 8-conductor, 18 AWG PVC shielded cable for remote, 100' max. length
  • Teflon Ferrule Kit
  • Stainless Steel Tags
  • Retractors
  • Sun shade accessory

FT4X Downloads

Model FT4X Information to View and/or Download
Model FT4X Datasheet
FT4X Model Codes
FT4X Flowmeter Features
FT4X Procurement Specifications
.pdf .docx
FT4X Instruction Manual
Troubleshooting Guide
CAL-V™ Certificate
Gas-SelectX® Datasheet
FT4X Power Supply Datasheet
Modbus View Information to View and/or Download
Modbus View Software
Modbus View Datasheet
Modbus View Manual
Model FT4X View™ Information to View and/or Download
FT4X View™ Software
FT4X View™ Datasheet
FT4X View™ Manual
VCP Driver (for FT4X View™ Software)

Note regarding VCP Driver: If the PC is connected to the Internet and running Windows® 7, 8, or 10, the PC will try to automatically load the VCP driver. If the driver does not load automatically, we have supplied a link above.

Note: For FT4X View™ software to function, please be sure to have a working version of Microsoft® Office installed on the PC before installing FT4X View™.

USB Driver and the Fox Thermal FT4X View™ Software
A USB driver is needed for FT4X View™ to run. If the USB drive does not install automatically, you will need to download it by following this link. Instructions are included on how to install it correctly.

Other Downloads

FT4X Dimensional Drawings

FT4X Insertion Models
Local electronics, probe without retractor
Local electronics, probe with retractor
Remote electronics, probe without retractor
Remote electronics, probe with retractor
FT4X with Crank Retractors
Local electronics with Crank Retractor
Remote electronics with Crank Retractor
FT4X Inline Models
Local electronics, NPT end connections
Local electronics, 150# flange end connections
Local electronics, 300# flange end connections
Remote electronics, NPT end connections
Remote electronics, 150# flange end connections
Remote electronics, 300# flange end connections
Fox 3D Viewer

FT4X Awards

FT4X O&G Engineering Product of the Year Award

Winner of Oil & Gas Engineering’s 2018 Product of the Year Award!

Fox Thermal’s Model FT4X has won the Silver Award in the Data & Analytics Category of Oil & Gas Engineering’s 2018 Product of the Year Award. Winning products have been reviewed by qualified Engineers in each category. The Data & Analytics Category focuses on products, software, and services that make the analysis or acquisition of data easier for users. The Data Logger on the FT4X allows users to store more than 7 years of history right at the point of measurement! Data is easily accessible through the flow meter’s front panel or by using the free FT4X View™ software to generate and print logs detailing meter configuration, Calibration Validation test results, gas composition, gas density, gross heating value, and much more!

FT4X Flow Control 2018 Innovation Award Honoree

Flow Control’s 2018 Innovation Award Honoree

The Fox Thermal Model FT4X Thermal Mass Flow Meter from Fox Thermal was designed for use in oil and gas applications such as flare and waste gas monitoring, gas studies, gas royalties and allocation. Each Model FT4X is equipped with the second generation of direct digitally controlled sensor (DDC-Sensor™) technology that provides the platform for the gas menu feature: Gas-SelectX®. Every Fox Model FT4X comes equipped with an advanced intrinsic data logger for advanced record-keeping and data retention.

Fox Thermal Model FT4X Flow Meter

The Fox Thermal Model FT4X is the most fully-featured Thermal Gas Mass Flow Meter offered from Fox Thermal.

The Model FT4X measures gas flow rate in standard units (SCFM, NM³/hr, LBS/HR, KG/HR & many more) without the need for temperature and pressure compensation.

A free software tool – FT4X View™ - is available for the Model FT4X that allows the user to connect to and configure the FT4X using a PC or laptop.

Common Features for Fox Thermal Model FT4X Flow Meter:

  • Measures process gas flow rate/total and temperature
  • Insertion probes (for 1.5" - 70" pipes); Inline flow bodies with NPT ends (1.5" - 3" pipes); Inline 150# & 300# Flanged flow bodies (1.5" - 6" pipes)
  • Equipped with the 2nd Generation DDC-Sensor™ (Direct Digitally Controlled)
  • Gas-SelectX® expanded gas selection menu. Choose from available list of gases/gas mixes to measure flow. NIST-traceable calibration
  • Advanced Data Logger with Real Time Clock and 40 24-Hour daily totals
  • Settable Contract Time defines Contract Day
  • A USB connection is standard (free FT4X View™ Software); Optional HART and RS485 Modbus communication protocols
  • Standard on-board display and configuration panel
  • Two standard isolated 4-20mA outputs: Channel 1 configured to indicate flow, fault indication per NAMUR NE43. HART communication option; Channel 2 configured to indicate either flow or temperature
  • One isolated open collector output for pulse/alarm
  • One switch input to reset total
  • Click the Approvals tab for Model FT4X Agency Approval details
  • Calibration Validation with the CAL-V™ test
  • NIST-traceable calibration
  • Wide measurement range
  • Flow Accuracy for air: ±1% R ±0.2% FS; Flow accuracy for other gases: ±1.5% R ±0.5% FS
  • 24 VDC in local or remote enclosures

For complete specs please see the Fox Thermal Model FT4X Flow Meter Datasheet.

Asking the right questions
for over 25 years.



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