Fox Thermal Model VF4 Vortex Shedding Flow Meter

Model VF4 flow meter

Vortex Series
The Fox Thermal Model VF4 vortex shedding flow meter is the newest product offered from Fox Thermal.
Key Features:

  • Inline, Reduced-bore, & Remote Styles
  • Measures Gas, Liquid, and Saturated Steam
  • Multivariable Transmitter
  • Scroll down for more features/benefits!

Try the Configurator/Sizing App

Click on the "Configure a VF4" button to get started.


The Power over Ethernet (PoE) option for the Vortex series of flow meters delivers both data and electrical power over a single Ethernet cable. This feature offers:

  • Simplified installation
  • Reduced installation costs and greater flexibility
  • Enhanced monitoring and control

Lower the overall infrastructur and installations costs with this advanced feature.

Try the Configurator/Sizing App

Click on the "Configure a VF3" button to get started.

More Info

Common Features for Fox Thermal Model VF4 Inline Flow Meter:

  • Measures gas, liquids, and steam
  • Inline line sizes from 0.5" (15mm) to 12" (300mm)
  • Inline reduced bore line sizes from 0.75" (20mm) x 0.5" (15mm) to 12" (300mm) x 10" (250mm)
  • Multivariable outputs for mass flow rate, volumetric flow rate, temperature, pressure, density, and energy (BTU) readings from a single installed devices and reduces initial cost, installation cost, and cost
  • Single process connection
  • Field-configurable ranges, alarms, outputs, and displays
  • Configuration via six push buttons or magnet through explosion-proof window
  • Temperature up to 750F (400C)
  • Pressure up to 1,500 psia (100 bara)
  • Calibration is valid for the life of the meter
  • Smart DSP electronics extends low-flow range down to a Reynolds number of 5,000
  • Rangeability up to 100:1
  • Mass flow equations for real gas, ideal gas, AGA-8 equations for natural gas, API 2540
  • Advanced serial communication options: BACnet/IP, Modbus TCP/IP, BACnet MS/TP, and Modbus RTU
  • Ideal for steam applications
    • Energy (BTU) monitoring for real-time measurement of energy consumption; compute and output energy use
    • Easy installation and commission
    • Loop powered to save on energy costs
  • DC or AC power in local or remote enclosures

VF4 Flow Meter Specs

Technical Specifications
Fox Thermal Model VF4 Vortex Shedding Flow Meter
Performance Specs
FLUID TYPE
LIQUIDS
GAS AND STEAM
Mass Flow Rate Accuracy:
± 1.0% of rate
over a 30:1 range*
± 1.5% of rate
over a 30:1 range*
Volumetric Flow Rate Accuracy:
± 0.7% of rate
over a 30:1 range*
± 1.0% of rate
over a 30:1 range*
Temperature Accuracy:
± 2°F (± 1°C)
± 2°F (± 1°C)
Pressure Accuracy:
± 0.3% of transducer
full scale
± 0.3% of transducer
full scale
Density Accuracy:
± 0.3% of reading
± 0.5% of reading
Repeatability:
Mass flow rate: ± 0.2% of reading
Volumetric flow rate: ± 0.1% of reading
Temperature: ± 0.2°F (± 0.1°C)
Pressure: ± 0.05% of full scale
Density: ± 0.1% of reading
Flow Response Time:
Adjustable from 1 to 100 seconds

Differential Pressure Requirements, ΔP
Low permanent pressure drop.
Material Compatability:
Any gas, liquid, or steam compatible with 316L stainless steel, C276 Hastalloy, or A105 carbon steel. Not recommended for multi-phase fluids.
Velocity Range:
Smart electronics corrects for lower flow down to a Reynolds number of 5000. The Reynolds number is calculated using the fluid's actual temperature and pressure monitored by the meter. Rangeability depends on the fluid, process connections, and pipe size. Consult factory for your application. Velocity rangeability under ideal conditions is as follows:
Liquids: 30:1, 1 foot per second velocity miniumum
30 feet per second velocity maximum.
Gases: 30:1, 300 feet per second velocity maximum
Minimum is fluid dependent: range must be calculated using below equations:
Pressure Drop Equations:
ΔP=0.00024ρV² English Units (ΔP in psi, ρ in lbs/ft³, V in ft/sec)
ΔP=0.00011ρV² Metric Units (ΔP in bar, ρ in kg/m³, V in m/sec)
Wetted Materials:
316L stainless steel
C276 Hastalloy or A105 carbon steel optional
Teflon-based thread sealant on pressure transducer
Enclosure:
NEMA 4X (IP66) cast enclosure
Electrical Ports:
Two 3/4-inch female NPT ports
Process Connections:
Wafer or 150, 300, 600, 900 bl ANSI flange
Mounting Connections:
No effect.
Installation Specs
(In number of internal diameters, D)
Straight Pipe Length Requirements
Upstream
Downstream
One 90° elbow before meter:
10 D
5 D
Two 90° elbow before meter:
15 D
5 D
Two 90° elbow before meter out of plane (if three 90° bends present, double recommended length):
30 D
10 D
Reduction before meter:
10 D
5 D
Expansion before meter:
20 D
5 D
Regulator or valve partially closed before meter (if valve wide open, base length requirements on fitting directly preceding it):
30 D
10 D
Operating Specs
Power Requirements:
DCL option: 12-36 VDC, 25mA, 1W max. loop powered (single output)
DCH option: 12-36 VDC, 300mA, 9W max. (multiple outputs)
DCHPOE option: 12-28 VDC or Power over Ethernet, 5W max (multiple outputs)
AC option: 100-240 VAC, 50/60Hz line power, 5W (multiple outputs)
Multiparameter Mass Options:
Specific power supply and wiring recommendations are dependent on the process requirements and stack type/electronics ordered. Refer to the model codes section of the VF4 Datasheet for power requirements stated for each stack type.
Use a Class 2 isolated power supply that is grounded, provides DC output, and has no more than 10% output ripple.
Installation (over-voltage) Category II for transient over-voltages.
AC and DC Mains supply voltage fluctuations are not to exceed ± 10% of the rated supply voltage range.
User is responsible for the provision of an external disconnect means, disconnect line 1 and line 2 when 220 / 240 VAC power used, also provide over-current protection for the equipment (both AC and DC models).
Display:
Alphanumeric 2 line x 16 character LCD digital display.
Six pushbuttons for full field configuration.
Pushbuttons can be operated with magnetic wand without removal of enclosure covers.
Switches (up, down, right, left, enter, exit).
Display can be mounted in 90° to 180° intervals for better viewing.
Process Fluid Temperature:
Standard Temperature Sensor: -330°F to 500°F (-200°C to 260°C)
High Temperature Sensor: Up to 750°F (400°C)
Ambient Temperature:
Operating: -40°F to 140°F (-40°C to 60°C)
Storage: -40°F to 185°F (-40°C to 85°C)
0-98% relative humidity, non-condensing conditions.
Output Signals:
Analog: One to three field rangeable, simultaneous linear 4-20mA output signals (1000 ohms maximum loop resistance) selected by user from the six parameters - mass flow rate, volumetric flow rate, temperature, pressure, density, and total/totalizer count.
Pulse: Pulse output for totalization is a 50-millisecond duration pulse operating a solid-state relay capable of switching 40 VDC 40 mA maximum HART standard, optional MODBUS RTU.
Frequency: Frequency output is used for a remote counter. It can be scaled to output a 1 to 10 kHz signal proportional to mass or volume flow, temperature, pressure, or density.
Note: All outputs are optically isolated and require external power for operation.
Alarms:
Up to three programmable solid-state relays for high, low, or window alarms capable of switching to 40 VDC, 40 mA maximum.
Totalizer:
Based on user-determined flow units, nine full digits, with rollover at 999,999,999; total stored in non-volatile memory.
Volumetric or Loop Powered Mass:
One analog, one totalizer pulse, HART
HART (with DD)
Modbus
BACnet
Turndown:
Turndown is application-dependent. Consult Fox Thermal Sizing Program for exact values.
Turndown can exceed 100:1.
Water Minimum and Maximum Flow Rates (English):
- - 0.5-inch 0.75-inch 1-inch 1.5-inch 2-inch 3-inch 4-inch 6-inch 8-inch 10-inch 12-inch
gpm 0.9
22		 1.4
40		 2.2
67		 5.5
166		 9.2
276		 21
618		 36
1076		 81
2437		 142
4270		 224
6715		 317
9501
Typical mass flow ranges are given in the table above. Precise flow ranges depend on the fluid and pipe size. Consult factory for sizing program.
Water Minimum and Maximimum Flow Rates (Metric):
- - 15 mm 20 mm 25 mm 40 mm 50 mm 80 mm 100 mm 150 mm 200 mm 250 mm 300 mm
m³/hr 0.2
5		 0.3
9		 0.5
15		 1.3
38		 2.1
63		 4.7
140		 8.1
244		 18
554		 32
970		 51
1525		 72
2158
Typical mass flow ranges are given in the table above. Precise flow ranges depend on the fluid and pipe size. Consult factory for sizing program.
Gas or Steam Maximum Velocity (English):
0.5-inch 0.75-inch 1-inch 1.5-inch 2-inch 3-inch 4-inch 6-inch 8-inch 10-inch 12-inch
ft/sec 175 250 250 300 300 300 300 300 300 300 300
Typical mass flow ranges are given in the table above. Precise flow ranges depend on the fluid and pipe size. Consult factory for sizing program.
Gas or Steam Maximum Velocity (Metric):
15 mm 20 mm 25 mm 40 mm 50 mm 80 mm 100 mm 150 mm 200 mm 250 mm 300 mm
m/sec 53 76 76 90 90 90 90 90 90 90 90
Typical mass flow ranges are given in the table above. Precise flow ranges depend on the fluid and pipe size. Consult factory for sizing program.
Process Fluid Pressure:
Process Connection Material Rating
Flanged 316L SS, A105 carbon steel, C276 Hastalloy 150, 300, 600, 900 lb
Wafer 316L SS, A105 carbon steel, C276 Hastalloy 600 lb
Process Transducer Pressure:
Pressure Sensor Ranges psia (bara)
Full Scale Operating Pressure Maximum Over-Range Pressure
psia bara psia bara
30 2 60 4
100 7 200 14
300 20 600 40
500 35 1000 70
1500 100 2750 175
PLEASE TURN YOUR DEVICE TO LANDSCAPE ORIENTATION.

VF4 Approvals

CE: Approved

FM and FMc: Approved

  • Class I, Division 1, Groups B, C, D;
  • Dust-ignition proof for Class II/III, Division 1, Groups E, F, G;
  • NEMA Type 4X and IP66
  • T6 at Tamb = -40°F to 60°C

ATEX: Approved

  • II 2 G Ex db IIB+H2 T6
  • II 2 D Ex tD A21 IP66 T85°C, Ta = -40°F to 60°C

IECEx: Approved

  • Ex d IIB+H2 T6
  • Ex tD A21 IP66 T85°C, Ta = -40°F to 60°C

Fox Thermal Certifications


Optional items available for the Model VF4 Flow Meter:

Talk with our application specialist or a rep near you for sizing and materials requirements. See Model Codes document for more details on options.

  • Material Certificates
  • Pressure Test Certificate
  • Certificate of Conformance
  • Certificate of Origin
  • NACE Certification
  • Oxygen Cleaning
  • PED Certified Bodies
  • Remote Cables
  • M20 Conversion Kits

VF4 Downloads

Model VF4 Information to View and/or Download
Model VF4 Datasheet
VF4 Model Codes
VF4 Flowmeter Features
VF4 Procurement Specifications
(.pdf)
(.docx)
VF4 Instruction Manual
Model VF4 Information to View and/or Download
Troubleshooting Guide

Note: Troubleshooting information located in product instruction manual.

Other Downloads

VF4 Dimensional Drawings

VF4 Inline Local Electronics Models
Local electronics, flanged models
Local electronics, flanged, reduced bore models
Local electronics, wafer style models
VF4 Remote Electronics Models
Remote electronics
Fox 3D Viewer
Fox Thermal Model VF4 Flow Meter

The Fox Thermal Model VF4 is the newest vortex shedding flow meter offered from Fox Thermal.

Common Features for Fox Thermal Model VF4 Flow Meter:

  • Measures gas, liquids, and steam
  • Inline line sizes from 0.5" (15mm) to 12" (300mm)
  • Inline reduced bore line sizes from 0.75" (20mm) x 0.5" (15mm) to 12" (300mm) x 10" (250mm)
  • Multivariable outputs for mass flow rate, volumetric flow rate, temperature, pressure, density, and energy (BTU) readings from a single installed devices and reduces initial cost, installation cost, and cost
  • Single process connection
  • Field-configurable ranges, alarms, outputs, and displays
  • Configuration via six push buttons or magnet through explosion-proof window
  • Temperature up to 750F (400C)
  • Pressure up to 1,500 psia (100 bara)
  • Calibration is valid for the life of the meter
  • Smart DSP electronics extends low-flow range down to a Reynolds number of 5,000
  • Rangeability up to 100:1
  • Mass flow equations for real gas, ideal gas, AGA-8 equations for natural gas, API 2540
  • Advanced serial communication options: BACnet/IP, Modbus TCP/IP, BACnet MS/TP, and Modbus RTU
  • Ideal for steam applications
    • Energy (BTU) monitoring for real-time measurement of energy consumption; compute and output energy use
    • Easy installation and commission
    • Loop powered to save on energy costs
  • DC or AC power in local or remote enclosures

For complete specs please see the Fox Thermal Model VF4 Flow Meter Datasheet.

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Fox Thermal | 399 Reservation Rd. | Marina, CA 93933 | (831) 384-4300 | www.foxthermal.com