Fox Thermal Model VF4 Vortex Shedding Flow Meter
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
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 |
