Fox Thermal Model FT4A Thermal Mass Flow Meter

Award Winning Model FT4A

FT4A Flow Meter
The Fox Thermal Model FT4A was the first meter to use the expanded Gas-SelectX® gas selection menu and the 3rd Generation DDC-Sensor™ design.

Key Features:

  • Insertion & Inline Styles
  • DDC-Sensor™ Technology
  • Gas-SelectX® Gas Selection Menu
  • CAL-V™ Calibration Validation
  • FC20 Flow Conditioner option
  • Scroll down for more features/benefits!

ModbusView™ Software
ModbusView™ is Fox Thermal software for FT4A meters equipped with the Modbus RTU (RS485) communication option. It provides a streamlined way to connect to compatible FT4A meters through the Modbus interface, access meter information, and support commissioning and ongoing monitoring. Use ModbusView™ to:

  • Connect to compatible FT4A 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: FT4A configured with the Modbus RTU communication option
Availability: Free download (see "Downloads")

FT4A View™ Software
FT4A View™ is Fox Thermal’s free PC-compatible software for connecting directly to an FT4A through its USB port. Use it to access and adjust meter settings in a clear visual interface, monitor data, troubleshoot meter operation, and document calibration-validation results. Use FT4A View™ to:

  • Access configuration parameters through pull-down menus and pop-up windows
  • Set measurement units, flow and temperature ranges, alarms, and other meter settings
  • Run CAL-V™ and save or print a Calibration Validation Certificate
  • Select or mix gases in Gas-SelectX® Menu
  • Use simulation mode to align the 4-20 mA output with PLC or DCS inputs
  • Review raw data for diagnosis and troubleshooting
  • Log data to an Excel® spreadsheet

Connection: USB to PC or laptop with working Microsoft Office and USB driver installed (see "Downloads")
Compatibility: FT4A flow meters
Availability: Free download (see "Downloads")

Calibration Validation
The CAL-V™ test is used for Calibration Validation on the Model FT4A. 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 FT4A 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.
*Natural gas refers to pipeline-quality, dry natural gas using the NAESB standard composition. For associated gas or other nonstandard natural-gas compositions, use the Gas-SelectX® custom gas-mix function or contact Fox Thermal for application support.

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 FT4A 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 FT4A View™ software.


Gas-SelectX® Datasheet
Configure the FT4A

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 FT4A Flow Meter:

  • Measures process gas flow rate/total and temperature
  • Insertion probes (for 1.5" - 70" pipes); Inline flow bodies with NPT ends (¾" - 3" pipes); Inline 150 lb. & 300 lb. Flanged flow bodies (¾" - 6" pipes)
  • Equipped with the 3rd Generation 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
  • One standard 4-20mA output proportional to mass flow rate; HART communication option
  • Second output can be ordered for pulse/alarm or Modbus RTU (RS485)
  • Standard display and configuration panel
  • Click the Approvals tab for Model FT4A Agency Approvals.
  • Calibration Validation with the CAL-V™ feature.
  • A USB connection is standard (free FT4A View™ Software)
  • ModbusView™ software for Modbus-equipped FT4A configurations
  • Wide measurement range
  • Flow Accuracy for air: ±1% R ±0.2% FS; Flow accuracy for other gases: ±1.5% R ±0.5% FS
  • 10-30 VDC in local enclosures
  • FC20 Flow Conditioner ordering option to reduce straight run requirements for insertion style flow meters

FT4A Flow Meter Specs

Technical Specifications
Fox Thermal Model FT4A 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 FT4A (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, LB/S, LB/M, LB/H, LB/D, KG/S, KG/M, KG/H, SLPM, MT/H
Flow Rates:
15 to 60,000 SFPM (0.07 to 283 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 FT4A 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
Temperature:
DDC-Sensor™: -40 to 250°F (-40 to 121°C)
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 24VDC, 6 watts
Full input power input range: 10 to 30VDC
A 20 Watt or greater power supply is recommended to power the FT4A to ensure the power supply can provide enough current under all temperature, ventilation, and power on conditions.
Inputs/Outputs
  • All outputs and communication circuits are galvanically isolated.
  • Standard 4-20mA output proportional to the flow rate; fault indication per NAMUR NE43; HART communication option.
  • The second output can be ordered for pulse/alarm or Modbus RTU (RS485).
  • Isolated pulse output: 5 to 24VDC, 20mA max, 0 to 100Hz for flow.
  • The pulse output can be used as an isolated solid state output for alarms.
Port:
Mini USB communication port is standard.
Software:
The free PC-based software tool - FT4A View™ - provides complete configuration, remote process monitoring, and data logging functions.
Optional serial communication:
Modbus RTU (RS485) (when no pulse output has been ordered).
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, Aluminum, dual conduit entries with ¾" FNPT.
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.

FT4A Approvals

CE: Approved

  • EMC Directive; 2014/30/EU
  • Emissions and Immunity Testing: EN61326-1:2013
  • Pressure Equipment Directive: 2014/68/EU
  • Weld Testing: EN ISO 15614-1 and EN ISO 9606-1, ASME B31.3

FM (U.S.) and FMc (Canada): Approved

  • Class I, Division 1, Groups B, C, D;
  • Class II, Division 1, Groups E, F, G;
  • Class III, Division 1; T4, Ta = -40°C to 70°C;
  • Class I, Zone 1, AEx/Ex db IIB+H2 T4; Gb Ta = -40°C to 70°C; Type 4X, IP66/67

ATEX (FM16ATEX0013X): Approved

  • II 2 G Ex db IIB+H2 T4; Gb Ta = -40°C to 70°C; IP66/67
  • II 2 D Ex tb IIIC T135°C; Db Ta = -40°C to 70°C; IP66/67

IECEx (IECEx FMG 16.0010X): Approved

  • Ex db IIB+H2 T4; Gb Ta = -40°C to 70°C; IP66/67
  • Ex tb IIIC T135°C; Db Ta = -40°C to 70°C; IP66/67

ATEX and IECEx Standards:

EN 60079-0:2012 + A11:2013
EN 60079-1:2014
EN 60079-31:2014
EN 60529:1991 + A1:2000

IEC 60079-0:2011
IEC 60079-1:2014
IEC 60079-31:2013
IEC 60529:2001

Fox Thermal Certifications

Optional items available for the Model FT4A 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 FT4A
  • AC to 24VDC power converter with DIN mounting rail
  • ModbusView™ software license for remote connectivity
  • USB remote connectivity kit (ModbusView RS485-to-USB converter)
  • RJ45 remote connectivity kit (ModbusView RS485-to-RJ45 converter)
  • Flow meter cleaned and bagged for Oxygen service
  • M20x1.5 wiring connection adapters (qty. 2 per meter)
  • Certificate of Conformance
  • Certificate of Origin
  • Material certificates for wetted parts
  • Extra Instruction Manual
  • 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
  • Stainless Steel Tags
  • Sun shade accessory
  • Retractors

FT4A Downloads

Model FT4A Information to View and/or Download
Model FT4A Datasheet
FT4A Model Codes
FT4A Flowmeter Features
FT4A Procurement Specifications
.pdf .docx
FT4A Instruction Manual
Troubleshooting Guide
CAL-V™ Certificate
Gas-SelectX® Datasheet
FT4A Power Supply Datasheet
Modbus View Information to View and/or Download
Modbus View Software
Modbus View Datasheet
Modbus View Manual
Model FT4A View™ Information to View and/or Download
FT4A View™ Software
FT4A View™ Datasheet
FT4A View™ Manual
VCP Driver (for FT4A 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.
A USB driver is needed for FT4A View™ to run. If the USB driver 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

FT4A Dimensional Drawings

FT4A Insertion Models
Local electronics, probe without retractor
Local electronics, probe with retractor
FT4A Inline Models
Local electronics, NPT end connections
Local electronics, 150# flange end connections
Local electronics, 300# flange end connections
Fox 3D Viewer

FT4A Awards

Winner of the 2017 Flow Control Innovation Award

Overall Winner for Flow Control’s 2017 Innovation Award!

As the Overall Winner of the 2017 Flow Control Innovation Awards, the Fox Thermal Model FT4A is the newest Thermal Gas Mass Flow Meter offered from Fox Thermal.

The Model FT4A has been been awarded the Overall Winner for this award due to its innovative design elements such as the 2nd Generation DDC-Sensor™ technology platform and the new expanded Gas-SelectX® gas menu selection tool. The Model FT4A measures gas flow rate in standard units without the need for temperature and pressure compensation.

Thank you for voting!

Read more in the case study.

Winner of the 2017 Processing Breakthrough Products Award

Winner of the Processing Magazine’s 2017 Breakthrough Product Award!

The Model FT4A is the latest product from Fox Thermal making waves in the flow meter market. The FT4A has won the 2017 Breakthrough Product Award from Processing Magazine.

The expanded Gas-SelectX gas selection menu, operated on an advanced platform made possible by the new 2nd generation DDC-Sensor™, has made an impression and paved the way for the Model FT4A to win this award.

The Model FT4A was designed for use in Oil & Gas applications and any application that has changing gas compositions. The Gas-SelectX menu allows the user to change the gas composition in the field without having to send the meter back to the factory for re-calibration thus saving the customer time, money, and avoiding process shut-downs. Click the green button on the left to check out the FT4A Product page for more information.

View the award announcement.

Fox Thermal Model FT4A Flow Meter

The Fox Thermal Model FT4A Thermal Gas Mass Flow Meter offered from Fox Thermal.

The Model FT4A 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 – FT4A View™ - is available for the Model FT4A that allows the user to connect to and configure the FT4A using a PC or laptop.

Common Features for Fox Thermal Model FT4A Flow Meter:

  • Measures process gas flow rate/total and temperature
  • Insertion probes (for 1.5" - 70" pipes); Inline flow bodies with NPT ends (¾" - 3" pipes); Inline 150 lb. & 300 lb. Flanged flow bodies (¾" - 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
  • One standard 4-20mA output proportional to mass flow rate; HART communication option
  • Second output can be ordered for pulse/alarm or RS485 Modbus RTU
  • Optional on-board display and configuration panel
  • Click the Approvals tab for Model FT4A Agency Approvals.
  • Calibration Validation with the CAL-V™ feature.
  • A USB connection is standard (free FT4A View™ Software)
  • Wide measurement range
  • Flow Accuracy for air: ±1% R ±0.2% FS; Flow accuracy for other gases: ±1.5% R ±0.5% FS
  • 10-30 VDC in local enclosures

For complete specs please see the Fox Thermal Model FT4A Flow Meter Datasheet.

Asking the right questions
for over 25 years.



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