Fox Thermal Model VF3 Vortex Shedding Flow Meter

Model VF3 flow meter

Vortex Series
The Fox Thermal Model VF3 vortex shedding flow meter is the newest product offered from Fox Thermal.
Key Features:

  • Insertion & Remote Styles
  • Measures Gas, Liquid, and Saturated Steam
  • Multivariable Transmitter
  • Available for hot tap installations
  • Scroll down for more features/benefits!

Try the Configurator/Sizing App

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


The Power over Ethernet (PoE) option for the 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 VF3 Insertion Flow Meter:

  • Measures gas, liquids, and steam
  • Insertion probes (for >2" pipes)
  • 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
  • Available for hot tap installations
  • Other vortex manufacturers are inline-only (no hot tap option)
  • 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; hot-tappable-no process shutdown
    • Loop powered to save on energy costs
  • DC or AC power in local or remote enclosures

VF3 Flow Meter Specs

Technical Specifications
Fox Thermal Model VF3 Vortex Shedding Flow Meter
Performance Specs
FLUID TYPE
LIQUIDS
GAS AND STEAM
Mass Flow Rate Accuracy:
± 1.5% of rate
over a 30:1 range*
± 2.0% of rate
over a 30:1 range*
Volumetric Flow Rate Accuracy:
± 1.2% of rate
over a 30:1 range*
± 1.5% 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. 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
Teflon® packing gland below 500°F (260°C)
Graphite packing gland below 500°F (260°C)
Teflon-based thread sealant on pressure transducer
Enclosure:
NEMA 4X (IP66) cast enclosure
Electrical Ports:
Two 3/4-inch female NPT ports
Process Connections:
2" MNPT, 150-lb, 300-lb, 600-lb, 900lb
Note: Refer to model codes and accessories for compatability of process connections with other features.
Mounting Connections:
Meter must be perpendicular within ± 5° of the pipe centerline.
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 VF3 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 Flow Rates (English):
- - 3-inch 6-inch 8-inch 12-inch 16-inch 24-inch
gpm 21
618		 81
2437		 142
4270		 317
9501		 501
15043		 1138
34144
Typical mass flow ranges are given in the table above. Precise flow ranges depend on the fluid and pipe size. VF3 insertion meters are applicable to pipe sizes from 2-inches and greater. Consult factory for sizing program.
Water Flow Rates (Metric):
- - 80 mm 150 mm 200 mm 300 mm 400 mm 600 mm
m³/hr 5.2
157		 20.4
614		 35.4
1062		 79.2
2337		 125
3753		 284
8537
Typical mass flow ranges are given in the table above. Precise flow ranges depend on the fluid and pipe size. VF3 insertion meters are applicable to pipe sizes from 2-inches and greater. Consult factory for sizing program.
Saturated Steam Minimum and Maximum Flow Rates (lb/hr):
Pressure 3-inch 6-inch 8-inch 12-inch 16-inch 24-inch
5 psig 205
2721		 800
10633		 1385
18412		 3099
41196		 4893
65039		 11132
147954
100 psig 486
14246		 1831
55674		 3170
96407		 7092
215703		 11197
340546		 25472
774698
200 psig 632
25948		 2471
101405		 4278
175595		 9572
392880		 15111
620268		 34377
1411029
300 psig 762
37652		 2976
147145		 5153
254799		 11530
570093		 18203
900047		 41410
2047489
400 psig 873
49494		 3412
193420		 5908
334930		 13219
749382		 20870
1183103		 47477
2691404
500 psig 974
61543		 3805
240507		 6588
416468		 14741
931816		 23272
1471125		 52942
3346615
Typical mass flow ranges are given in the table above. Precise flow ranges depend on the fluid and pipe size. VF3 insertion meters are applicable to pipe sizes from 2-inches and greater. Consult factory for sizing program.
Saturated Steam Minimum and Maximum Flow Rates (kg/hr):
Pressure 80 mm 150 mm 200 mm 300 mm 400 mm 600 mm
0 barg 81
938		 316
3667		 548
6350		 1226
14209		 1936
22432		 4404
51039
5 barg 187
4986		 729
19486		 1263
33742		 2826
75495		 4461
119189		 10151
271187
10 barg 249
8859		 972
34620		 1683
59949		 3767
134132		 5947
211764		 13530
481821
15 barg 298
12700		 1164
49629		 2016
85939		 4510
192283		 7120
303570		 16200
690705
20 barg 340
16550		 1329
64676		 2301
111995		 5148
250581		 8128
395609		 18493
900119
30 barg 413
24357		 1612
95187		 2791
164827		 6246
368789		 9860
582234		 22435
1324739
Typical mass flow ranges are given in the table above. Precise flow ranges depend on the fluid and pipe size. VF3 insertion meters are applicable to pipe sizes from 2-inches and greater. Consult factory for sizing program.
Air Minimum and Maximum Flow Rates (scfm):
Pressure 3-inch 6-inch 8-inch 12-inch 16-inch 24-inch
0 psig 56
924		 220
3611		 381
6253		 852
13991		 1345
22089		 3059
50250
100 psig 157
7236		 615
28379		 1065
48696		 2383
109564		 3763
172977		 8560
393500
200 psig 216
13588		 843
53101		 1460
91950		 3266
205732		 5156
324804		 11729
738886
300 psig 262
19974		 1022
78059		 1770
135169		 3960
302430		 6251
477467		 14221
1086176
400 psig 301
26391		 1175
103136		 2034
178593		 4551
399588		 7186
630859		 16346
1435121
500 psig 335
32834		 1310
128314		 2269
222191		 5077
497136		 8015
784865		 18233
1785464
Air at 70°F and 1 atmosphere. Typical mass flow ranges are given in the table above. Precise flow ranges depend on the fluid and pipe size. VF3 insertion meters are applicable to pipe sizes from 2-inches and greater. Consult factory for sizing program.
Air Minimum and Maximum Flow Rates (nm³/hr):
Pressure 80 mm 150 mm 200 mm 300 mm 400 mm 600 mm
0 barg 89
1463		 347
5716		 601
9897		 1345
22145		 2124
34962		 4833
79547
5 barg 217
8702		 847
34006		 1467
58885		 3282
131751		 5181
208004		 11788
473266
10 barg 294
15975		 1148
62430		 1987
108105		 4446
241878		 7020
381870		 15972
868857
15 barg 355
23280		 1385
90979		 2399
157542		 5368
352487		 8474
556497		 19282
1266182
20 barg 407
30615		 1589
119642		 2751
207175		 6156
463539		 9718
731823		 22112
1665095
30 barg 495
45361		 1934
177268		 3349
306961		 7493
686801		 11829
1084302		 26915
2467081
Air at 20°C and 1 atmosphere. Typical mass flow ranges are given in the table above. Precise flow ranges depend on the fluid and pipe size. VF3 insertion meters are applicable to pipe sizes from 2-inches and greater. Consult factory for sizing program.
Process Fluid Pressure:
Probe Seal Process Connection Material Rating
Compression Fitting 2-inch male NPT 316L SS ANSI 600 lb
Compression Fitting 2-inch 150 lb flange 316L SS ANSI 150 lb
Compression Fitting 2-inch 300 lb flange 316L SS ANSI 300 lb
Compression Fitting 2-inch 600 lb flange 316L SS ANSI 600 lb
Compression Fitting 2-inch 900 lb flange 316L SS ANSI 900 lb
Packing Gland 2-inch male NPT 316L SS 50 psig
Packing Gland 2-inch 150 lb flange 316L SS 50 psig
Packing Gland 2-inch 300 lb flange 316L SS 50 psig
Packing Gland & Removable Retractor 2-inch male NPT 316L SS ANSI 300 lb
Packing Gland & Removable Retractor 2-inch 150 lb flange 316L SS ANSI 300 lb
Packing Gland & Removable Retractor 2-inch 300 lb flange 316L SS ANSI 300 lb
Packing Gland & Permanent Retractor 2-inch male NPT 316L SS ANSI 600 lb
Packing Gland & Permanent Retractor 2-inch 150 lb flange 316L SS ANSI 150 lb
Packing Gland & Permanent Retractor 2-inch 300 lb flange 316L SS ANSI 300 lb
Packing Gland & Permanent Retractor 2-inch 600 lb flange 316L SS ANSI 600 lb
PLEASE TURN YOUR DEVICE TO LANDSCAPE ORIENTATION.

VF3 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 VF3 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
  • Removable Retractors
  • Isolation Gate Valves
  • Mounting Accessories

VF3 Downloads

Model VF3 Information to View and/or Download
Model VF3 Datasheet
VF3 Model Codes
VF3 Flowmeter Features
VF3 Procurement Specifications
(.pdf)
(.docx)
VF3 Instruction Manual
Model VF3 Information to View and/or Download
Troubleshooting Guide

Note: Troubleshooting information located in product instruction manual.

Other Downloads

VF3 Dimensional Drawings

VF3 Insertion Local Electronics Models
Local electronics, compression models
Local electronics, packing gland models
Local electronics, packing gland with retractor models
VF3 Remote Electronics Models
Remote electronics
Fox 3D Viewer
Fox Thermal Model VF3 Flow Meter

The Fox Thermal Model VF3 is the newest vortex shedding flow meter offered from Fox Thermal.

Common Features for Fox Thermal Model VF3 Flow Meter:

  • Measures gas, liquids, and steam
  • Insertion probes (for >2" pipes)
  • 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
  • Available for hot tap installations
  • Other vortex manufacturers are inline-only (no hot tap option)
  • 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; hot-tappable-no process shutdown
    • 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 VF3 Flow Meter Datasheet.

Asking the right questions
for over 25 years.



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