ABB FV4000-VT4 User manual

Operating Instruction
D184B097U02
V
ortex Flowmeter / Swirl Flowmete
r
FV4000-VT4/VR4 / FS4000-ST4/SR4

Blinder Text
2 FV4000-VT4/VR4 / FS4000-ST4/SR4 D184B097U02
Vortex Flowmeter / Swirl Flowmeter
FV4000-VT4/VR4 / FS4000-ST4/SR4
Operating Instruction
D184B097U02
02.2009
Rev. 08
Manufacturer:
ABB Automation Products GmbH
Dransfelder Straße 2
D-37079 Göttingen
Germany
Tel.: [phone]
Fax: [phone]
[email protected]
© Copyright 2009 by ABB Automation Products GmbH
Subject to changes without notice
This document is protected by copyright. It assists the user in safe and efficient operation of the device.
The contents of this document, whether whole or in part, may not be copied or reproduced without prior
approval by the copyright holder.
Contents

Contents
D184B097U02 FV4000-VT4/VR4 / FS4000-ST4/SR4 3
1Safety....................................................................................................................................................................8
1.1 General information and notes for the reader ................................................................................................8
1.2 Intended use...................................................................................................................................................8
1.3 Improper use ..................................................................................................................................................9
1.4 Technical limit values .....................................................................................................................................9
1.5 Approved media ...........................................................................................................................................10
1.6 Warranty provisions......................................................................................................................................10
1.7 Plates and symbols ......................................................................................................................................11
1.7.1 Safety/warning symbols, note symbols.................................................................................................11
1.7.2 Name Plate / Factory Tag .....................................................................................................................12
1.8 Target groups and qualifications ..................................................................................................................15
1.9 Returning devices.........................................................................................................................................15
1.10 Disposal........................................................................................................................................................16
1.10.1 Information on WEEE Directive 2002/96/EC (Waste Electrical and Electronic Equipment).................16
1.10.2 RoHS directive 2002/95/EC ..................................................................................................................16
1.11 Transport safety information ........................................................................................................................17
1.12 Installation safety information.......................................................................................................................17
1.13 Safety information for electrical installation..................................................................................................18
1.14 Safety information for operation ...................................................................................................................18
1.15 Safety instructions for operation in hazardous areas...................................................................................18
1.16 Safety information for maintenance and inspection .....................................................................................19
2Design and function..........................................................................................................................................20
2.1 Principles of measurement...........................................................................................................................20
2.1.1 Vortex flowmeter ...................................................................................................................................20
2.1.2 Swirl flowmeter......................................................................................................................................22
2.2 Design ..........................................................................................................................................................23
2.3 Device designs .............................................................................................................................................24
2.3.1 Compact design ....................................................................................................................................24
2.3.2 Remote mount design ...........................................................................................................................24
3Transport............................................................................................................................................................25
3.1 Inspection .....................................................................................................................................................25
3.2 Transport of flanged units smaller than DN 350 ..........................................................................................25
3.3 Transport of flanged units larger than DN 300.............................................................................................25
4Mounting ............................................................................................................................................................26
4.1 General information on installation...............................................................................................................26
4.2 Installation Requirements.............................................................................................................................27
4.3 Recommended inflow and outflow sections.................................................................................................28
4.3.1 Vortex flowmeter ...................................................................................................................................28
4.3.2 Swirl flowmeter......................................................................................................................................28

Contents
4 FV4000-VT4/VR4 / FS4000-ST4/SR4 D184B097U02
4.4 Installation at high media temperatures > 150°C (302 F) ............................................................................29
4.5 Installation for pressure and temperature measurement .............................................................................29
4.6 Installation of final controlling equipment .....................................................................................................30
4.6.1 Vortex flowmeter ...................................................................................................................................30
4.6.2 Vortex and Swirl flowmeters..................................................................................................................30
4.7 Mounting the meter tube ..............................................................................................................................31
4.8 Centering the wafer design ..........................................................................................................................32
4.9 Flowmeter insulation ....................................................................................................................................33
4.10 Transmitter orientation .................................................................................................................................34
4.11 Rotating the display......................................................................................................................................35
4.12 Flowmeter sizes, flow range.........................................................................................................................36
4.12.1 Flow ranges, FV4000 vortex flowmeter ................................................................................................36
4.12.2 Flow ranges, swirl flowmeter FS4000 ...................................................................................................37
5Electrical connection ........................................................................................................................................38
5.1 Cable connection area .................................................................................................................................39
5.1.1 HART design.........................................................................................................................................39
5.1.2 Fieldbus design .....................................................................................................................................41
5.2 Cable connection..........................................................................................................................................42
5.2.1 Standard design, HART ........................................................................................................................42
5.2.2 Connection via flameproof cable gland (Ex d design) ..........................................................................42
5.2.3 Standard design, PROFIBUS PA / FOUNDATION Fieldbus................................................................45
5.2.4 Separate design ....................................................................................................................................47
5.3 M12 plug-in connector, PROFIBUS PA .......................................................................................................50
5.4 Switching output...........................................................................................................................................51
5.5 Configuration of the switching output ...........................................................................................................52
5.6 Functional ground/Equipotential bonding.....................................................................................................54
6Commissioning..................................................................................................................................................55
6.1 Preliminary checks prior to start-up..............................................................................................................55
6.2 Commissioning the unit................................................................................................................................55
6.2.1 Switching on the supply power .............................................................................................................55
6.2.2 Device configuration..............................................................................................................................55
6.3 Information on voltage/current consumption................................................................................................55
6.4 Setting the bus address (PROFIBUS PA)....................................................................................................56
6.5 Setting the bus address (FOUNDATION Fieldbus) .....................................................................................57
6.6 Checking the parameters .............................................................................................................................58
7Communication .................................................................................................................................................59
7.1 HART protocol communication ....................................................................................................................59
7.2 PROFIBUS PA communication....................................................................................................................61
7.3 FOUNDATION Fieldbus communication......................................................................................................64
7.4 Software history............................................................................................................................................67

Contents
D184B097U02 FV4000-VT4/VR4 / FS4000-ST4/SR4 5
7.4.1 TRIO-WIRL FV4000 HART version ......................................................................................................67
7.4.2 TRIO-WIRL FV4000 Profibus PA..........................................................................................................67
7.4.3 TRIO-WIRL FV4000 FOUNDATION Fieldbus ......................................................................................67
8Parameterization................................................................................................................................................68
8.1 Standard display format ...............................................................................................................................68
8.2 Operation using the buttons on the transmitter............................................................................................69
8.3 Navigation and data entry ............................................................................................................................71
8.3.1 Selecting parameters in a submenu .....................................................................................................71
8.3.2 Changing a parameter value.................................................................................................................71
8.3.3 Saving parameters ................................................................................................................................71
8.4 Parameter overview .....................................................................................................................................72
8.4.1 Menu levels ...........................................................................................................................................72
8.4.2 Menu level parameters..........................................................................................................................72
8.5 Programming protection...............................................................................................................................73
8.5.1 Deactivating programming protection ...................................................................................................73
8.5.2 Activating programming protection .......................................................................................................74
8.6 Menu structure .............................................................................................................................................75
8.6.1 Menu structure – Enhancement for HART............................................................................................83
8.6.2 Menu structure – Enhancement for PROFIBUS PA .............................................................................85
8.6.3 Menu structure – Enhancement for FOUNDATION Fieldbus...............................................................88
8.7 Description of parameters ............................................................................................................................90
8.7.1 Nominal size..........................................................................................................................................90
8.7.2 Mean k factor ........................................................................................................................................90
8.7.3 Hardware config. ...................................................................................................................................91
8.7.4 Error 3/9 ................................................................................................................................................92
8.7.5 Standard factor......................................................................................................................................93
8.7.6 Operating density ..................................................................................................................................93
8.8 Parameterization of gases, steams, and liquids...........................................................................................94
9Error messages .................................................................................................................................................96
9.1 Error register ................................................................................................................................................96
9.1.1 Error register display when no errors are pending................................................................................96
9.1.2 Error register display when errors are pending.....................................................................................96
9.1.3 Power failure totalizer............................................................................................................................96
9.1.4 Clearing the error register .....................................................................................................................96
9.2 Error description ...........................................................................................................................................97
10 Maintenance / Repair.........................................................................................................................................98
10.1 Returning devices.........................................................................................................................................98
10.1.1 Contact information ...............................................................................................................................99
10.2 Maintenance for the flowmeter...................................................................................................................100
10.3 Cleaning .....................................................................................................................................................100

Contents
6 FV4000-VT4/VR4 / FS4000-ST4/SR4 D184B097U02
10.4 Replacing the transmitter ...........................................................................................................................101
10.5 Disassembling the flowmeter .....................................................................................................................103
11 Ex relevant specifications ..............................................................................................................................104
11.1 General technical data for hazardous areas ..............................................................................................104
11.1.1 HART devices .....................................................................................................................................104
11.1.2 Fieldbus devices .................................................................................................................................105
11.1.3 Differences between explosion-proof designs with regard to safety engineering...............................106
11.2 Ex "ib" / Ex "n" design for VT41/ST41 and VR41/SR41 (4 ... 20 mA / HART)...........................................107
11.2.1 Supply power or supply current ..........................................................................................................107
11.2.2 Approval data for hazardous areas.....................................................................................................108
11.2.3 Medium temperatures / Temperature classes ....................................................................................108
11.3 Ex "d" / Ex "ib" / Ex "n" design for VT42/ST42 and VR42/SR42 (4 ... 20 mA / HART)..............................109
11.3.1 Supply power or supply current ..........................................................................................................110
11.3.2 Approval data for hazardous areas.....................................................................................................110
11.3.3 Medium temperatures / Temperature classes ....................................................................................111
11.4 FM approval design for the USA and Canada for VT43/ST43 and VR43/SR43 (4 ... 20 mA / HART)......111
11.4.1 Supply power or supply current ..........................................................................................................112
11.4.2 Medium temperatures / Temperature classes ....................................................................................112
11.4.3 Approval data for hazardous areas.....................................................................................................112
11.4.4 Trio-Wirl control drawing .....................................................................................................................113
11.5 EEX "ia" design for VT4A/ST4A and VR4A/SR4A (fieldbus).....................................................................114
11.5.1 PROFIBUS PA electrical connection ..................................................................................................114
11.5.2 FOUNDATION Fieldbus electrical connection....................................................................................114
11.5.3 Approval data for hazardous areas.....................................................................................................115
11.5.4 Medium temperatures / Temperature classes ....................................................................................115
12 Specifications ..................................................................................................................................................116
12.1 Static overpressure in the case of fluids ....................................................................................................116
12.2 Standard densities of selected gases ........................................................................................................116
12.3 Overload capability.....................................................................................................................................116
12.4 Measured value deviation for flow measurement ......................................................................................116
12.4.1 Minimum Reynolds number Re min for linear start of scale value......................................................116
12.4.2 Reproducibility as a percentage of the measured value.....................................................................116
12.5 Measured value deviation for temperature.................................................................................................117
12.6 Temperature of medium.............................................................................................................................117
12.7 Reference conditions for flow measurement..............................................................................................117
12.8 Process connections ..................................................................................................................................117
12.9 Materials.....................................................................................................................................................118
12.10 Ambient conditions.....................................................................................................................................119
12.10.1 Permissible operating pressures FV4000...........................................................................................120
12.10.2 Permissible operating pressures FS4000...........................................................................................121

Contents
D184B097U02 FV4000-VT4/VR4 / FS4000-ST4/SR4 7
12.11 Transmitter .................................................................................................................................................122
12.11.1 General specifications.........................................................................................................................122
13 Appendix ..........................................................................................................................................................124
13.1 Additional documents.................................................................................................................................124
13.2 Approvals and certifications .......................................................................................................................124
13.3 Overview of technical design and setting parameters ...............................................................................130
14 Index .................................................................................................................................................................132

Safety
8 FV4000-VT4/VR4 / FS4000-ST4/SR4 D184B097U02
1 Safety
1.1 General information and notes for the reader
Read these instructions carefully prior to installing and commissioning the device.
These instructions are an important part of the product and must be kept for later use.
These instructions are intended as an overview and do not contain detailed information on all
designs for this product or every possible aspect of installation, operation and maintenance.
For additional information or in case specific problems occur that are not discussed in these
instructions, contact the manufacturer.
The content of these instructions is neither part of any previous or existing agreement, promise
or legal relationship nor is it intended to change the same.
This product is built based on state-of-the-art technology and is operationally safe. It has been
tested and left the factory in a safe, maintenance-free state. The information in the manual must
be observed and followed in order to maintain this state throughout the period of operation.
Modifications and repairs to the product may only be performed if expressly permitted by these
instructions.
Only by observing all of the safety information and all safety/warning symbols in these
instructions can optimum protection of both personnel and the environment, as well as safe and
fault-free operation of the device, be ensured.
Information and symbols directly on the product must be observed. They may not be removed
and must be fully legible at all times.
1.2 Intended use
This device is intended for the following uses:
• To convey fluids, gases (including unstable gases), and steams
• To measure the flow of the operating volume in mass flow or standard units under constant
operating conditions (pressure, temperature)
• To measure the flow of saturated steam in mass flow units at varying
temperatures/pressures, if the flowmeter sensor is fitted with a temperature sensor (option)
The following items are included in the intended use:
• Read and follow the instructions in this manual.
• Observe the technical ratings; refer to the section “Technical limit values”.
• Use only allowed liquids for measurement; refer to the section “Allowed fluids”.

Safety
D184B097U02 FV4000-VT4/VR4 / FS4000-ST4/SR4 9
1.3 Improper use
The following uses of the device are prohibited:
• Operation as a flexible adapter in piping, e. g., to compensate for pipe offsets, pipe
vibrations, pipe expansions, etc.
• Use as a climbing aid, e. g., for assembly purposes.
• Use as a support for external loads, e. g., as a support for pipes, etc.
• Material gain, e. g., by painting over the name plate or adding parts by welding / soldering.
• Material loss, e. g., by drilling the housing.
Repairs, alterations, and enhancements, or the installation of replacement parts, are only
permissible insofar as these are described in the manual. Approval by ABB Automation
Products GmbH must be sought for any activities beyond this scope. Repairs performed by
ABB-authorized specialist shops are excluded from this.
1.4 Technical limit values
The meter has been designed for use exclusively within the values stated on the name plate
and within the technical limit values specified on the data sheets.
The following technical limit values must be observed:
• The permissible operating pressure (PS) and the permissible temperature of the medium
(TS) must not exceed the pressure/temperature values (p/T ratings).
• The maximum operating temperature must not be exceeded.
• The permitted operating temperature must not be exceeded.
• The housing protection type must be observed.

Safety
10 FV4000-VT4/VR4 / FS4000-ST4/SR4 D184B097U02
1.5 Approved media
When using media, please note:
• Media (fluids) may only be used if, based on the state of the art or the operating experience
of the user, it can be assured that chemical and physical properties of the components
coming into contact with the fluids will not be adversely affected during the operating period.
• Specifically chloride media can cause not visible corrosion damages to all media wetted
components so that fluid can lead. The suitability of these materials for each application by
the operator to examine.
• Media (fluids) with unknown properties or abrasive media may only be used if the operator
can perform regular and suitable tests to ensure the safe condition of the meter.
• Observe the information on the name plate.
The meter tube, solid bodies (FV4000-VR4, FV4000-VT4 Vortex flowmeters only), inlet and
outlet pipes (FS4000-SR4, FS4000-ST4 Swirl flowmeters only), sensor and gasket come into
contact with the measured medium.
1.6 Warranty provisions
Using the device in a manner that does not fall within the scope of its intended use, disregarding
this manual, using underqualified personnel, or making unauthorized alterations releases the
manufacturer from liability for any resulting damage. This renders the manufacturer's warranty
null and void.

Safety
D184B097U02 FV4000-VT4/VR4 / FS4000-ST4/SR4 11
1.7 Plates and symbols
1.7.1 Safety/warning symbols, note symbols
DANGER – <Serious damage to health / risk to life>
This symbol in conjunction with the signal word "Danger" indicates an imminent danger.
Failure to observe this safety information will result in death or severe injury.
DANGER – <Serious damage to health / risk to life>
This symbol in conjunction with the signal word "Danger" indicates an imminent electrical
hazard. Failure to observe this safety information will result in death or severe injury.
WARNING – <Bodily injury>
This symbol in conjunction with the signal word “Warning“ indicates a possibly dangerous
situation. Failure to observe this safety information may result in death or severe injury.
WARNING – <Bodily injury>
This symbol in conjunction with the signal word "Warning" indicates a potential electrical
hazard. Failure to observe this safety information may result in death or severe injury.
CAUTION – <Minor injury>
This symbol in conjunction with the signal word “Caution“ indicates a possibly dangerous
situation. Failure to observe this safety information may result in minor or moderate injury.
This may also be used for property damage warnings.
ATTENTION – <Property damage>!
The symbol indicates a potentially damaging situation.
Failure to observe this safety information may result in damage to or destruction of the product
and/or other system components.
IMPORTANT (NOTICE)
This symbol indicates operator tips, particularly useful information, or important information
about the product or its further uses. It does not indicate a dangerous or damaging situation.

Safety
12 FV4000-VT4/VR4 / FS4000-ST4/SR4 D184B097U02
1.7.2 Name Plate / Factory Tag
The factory tag or name plate can be found in the following places on the meter housing:
G00730
21
3
Fig. 1
1 Name plate
2 Name plate, hazardous area
3 Factory tag
1.7.2.1 Identifying the meter design
1. Identifying the model:
The model number of the meter (see no. 1 in the description of the name plates) can be
found on the name plate. The connection diagram appears in the section titled "Electrical
connection". Technical data, material load curves, etc., appear sorted by model in the
section titled "Technical data".
2. Identifying the transmitter design:
The transmitter design can be identified from the name plate.
3. Identifying the software version:
The software version can be displayed when the transmitter is switched on.

Safety
D184B097U02 FV4000-VT4/VR4 / FS4000-ST4/SR4 13
1.7.2.2 Name plates
G00723
Fig. 2: Name plate
G00722
Fig. 3: Name plate, hazardous area

Safety
14 FV4000-VT4/VR4 / FS4000-ST4/SR4 D184B097U02
1.7.2.3 Factory Tag
The factory tag is located on the flowmeter sensor housing. If the pressure equipment is subject
to the PED (see section 3 para. 3 PED 97/23/EC), two labels are required:
Pressure equipment subject to PED
S.-Nr.: 0012345
0045
DN50/PN40
Material: 1.4571 / PTFE
Manufactured: 2002 PED: Fluid 1, Gas
ABB Automation Products GmbH
37070 Göttingen - Germany
/ Hast.C-4
1
2
3
4
5
6
G00002
Fig. 4
1 CE mark (with number of labeled
location) to confirm the device meets the
requirements of pressure equipment
directive 97/23/EC.
2 Serial number for identification of the
pressure equipment by the manufacturer.
3 Nominal size and nominal pressure rating
of pressure equipment.
4 Flange material, liner material and
electrode material (wetted parts).
5 Year of manufacture and specification of
fluid group as per the pressure
equipment directive (PED). Fluid group 1
= hazardous liquids, gaseous.
6 Manufacturer of the pressure equipment.
Pressure equipment outside the applicable range of the PED
S.-Nr.: 0012345
DN50/PN40
Material: 1.4571 / PTFE
Manufactured: 2002 PED: SEP
ABB Automation Products GmbH
37070 Göttingen - Germany
/ Hast.C-4
G00003
Fig. 5
The factory tag contains most of the specifications included on the plate described above with
the following differences:
• There is no CE mark because the pressure equipment, as per section 3 para. 3 of the PED,
is outside the applicable range of the pressure equipment directive 97/23/EC.
• The reason for the exception is specified in section 3 para. 3 of the PED. The pressure
equipment is categorized as SEP (= sound engineering practice).
Important
If the factory tag is not present, the device is not in compliance with directive 97/23/EC. The
exception applies for water, power and connected equipment accessories in accordance with
guideline 1/16 of sec. 1 para. 3.2 of the pressure equipment directive.

Safety
D184B097U02 FV4000-VT4/VR4 / FS4000-ST4/SR4 15
1.8 Target groups and qualifications
Installation, commissioning, and maintenance of the product may only be performed by trained
specialist personnel who have been authorized by the plant operator to do so. The specialist
personnel must have read and understood the manual and comply with its instructions.
Prior to using corrosive and abrasive materials for measurement purposes, the operator must
check the level of resistance of all parts coming into contact with the materials to be measured.
ABB Automation Products GmbH will gladly support you in selecting the materials, but cannot
accept any liability in doing so.
The operators must strictly observe the applicable national regulations with regards to
installation, function tests, repairs, and maintenance of electrical products.
1.9 Returning devices
Use the original packaging or a suitably secure packaging for returning the device for repair or
for recalibration. Include the properly filled out return form (see attachment) with the device.
According to EC guidelines for hazardous materials, the owner of hazardous waste is
responsible for its disposal or must observe the following regulations for its shipping:
All delivered devices to ABB Automation Products GmbH must be free from any hazardous
materials (acids, alkali, solvents, etc.).
Rinse out and neutralize hazardous materials from all hollow spaces such as between meter
tube and housing. These activities must be confirmed in writing using the return form.

Safety
16 FV4000-VT4/VR4 / FS4000-ST4/SR4 D184B097U02
1.10 Disposal
ABB Automation Products GmbH actively promotes environmental awareness and has an
operational management system that meets the requirements of DIN EN ISO 9001:2000,
EN ISO 14001:2004, and OHSAS 18001. Our products and solutions are intended to have
minimum impact on the environment and persons during manufacturing, storage, transport, use,
and disposal.
This includes the environmentally friendly use of natural resources. ABB conducts an open
dialog with the public through its publications.
This product/solution is manufactured from materials that can be reused by specialist recycling
companies.
1.10.1 Information on WEEE Directive 2002/96/EC (Waste Electrical and Electronic Equipment)
This product/solution is not subject to the WEEE directive 2002/96/EC and relevant national
laws (e. g., ElektroG in Germany).
The product/solution must be disposed of at a specialized recycling facility. Do not use
municipal garbage collection points. According to the WEEE Directive 2002/96/EC, only
products used in private applications may be disposed of at municipal garbage facilities. Proper
disposal prevents negative effects on people and the environment, and supports the reuse of
valuable raw materials.
If it is not possible to dispose of old equipment properly, ABB Service can accept and dispose of
returns for a fee.
1.10.2 RoHS directive 2002/95/EC
With the Electrical and Electronic Equipment Act (ElektroG) in Germany, the European
directives 2002/96/EC (WEEE) and 2002/95/EC (RoHs) are translated to national law. ElektroG
defines the products that are subject to regulated collection and disposal or reuse in the event
of disposal or at the end of their service life. ElektroG also prohibits the marketing of electrical
and electronic equipment that contains a specific amount of lead, cadmium, mercury,
hexavalent chromium, polybrominated biphenyls (PBB) and polybrominated diphenyl ethers
(PBDE) (also known as hazardous substances with restricted uses).
The products provided to you by ABB Automation Products GmbH do not fall within the current
scope of the directive on waste from electrical and electronic equipment according to ElektroG.
If the necessary components are available on the market, these substances will no longer be
used in new product development.

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D184B097U02 FV4000-VT4/VR4 / FS4000-ST4/SR4 17
1.11 Transport safety information
Please consider the following when transporting the device (in particular if your device weighs
more than 50 kg):
• The fact that the center of gravity might not be in the center of the unit
• Any available attachment points
• Transportation safety equipment (e. g. gaskets for openings)
1.12 Installation safety information
Observe the following instructions:
• The flow direction must correspond to the direction indicated on the meter, if labeled.
• The maximum torque must not be exceeded for all flange connections.
• The meters must be installed without mechanical tension (torsion, bending).
• Wafer units must be installed with coplanar counter flanges.
• Equipment must only be installed for the intended operating conditions and with suitable
gaskets.
• Flange bolts and nuts must be secured to provide protection against pipeline vibrations.
• The required length of straight pipeline must be provided upstream and downstream of the
meter.
• The pipeline must be supported upstream and downstream of the meter.

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18 FV4000-VT4/VR4 / FS4000-ST4/SR4 D184B097U02
1.13 Safety information for electrical installation
Electrical connections may only be established by authorized specialist personnel in
accordance with the electrical circuit diagrams.
The electrical connection information in the manual must be observed; otherwise, the applicable
protection type may be affected.
Ground the measurement system according to requirements.
Important
The transmitter meets the EMC requirements set out in EN 61326 / NAMUR NE21. There is
no EMC protection or protection against accidental contact when the housing cover is open.
Please observe the specific information about meters for hazardous areas in the section titled
"Technical data for hazardous areas".
1.14 Safety information for operation
Operation with abrasive fluids and/or cavitation can damage pressurized components.
During operation with hot fluids, contact with the surface may result in burns.
Aggressive fluids may result in corrosion and abrasion of the parts that come into contact with
the medium. As a result, pressurized fluids may escape prematurely.
Due to wear on the flange gasket, a pressurized medium may escape
Important
• As a general rule, when operating the meter, the detailed information in these operating
instructions on the subjects of "electrical safety" and "electromagnetic compatibility" must
be observed.
• For operation in potentially explosive areas, observe the relevant information in these
operating instructions.
1.15 Safety instructions for operation in hazardous areas
Specific requirements affecting the connection for the supply power and the switching output
apply for operation in hazardous areas. Please follow the instructions in the section titled
"Technical data for hazardous areas".

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D184B097U02 FV4000-VT4/VR4 / FS4000-ST4/SR4 19
1.16 Safety information for maintenance and inspection
Warning - Potential damage to parts!
The electronic components of the printed circuit board can be damaged by static electricity
(observe ESD guidelines).
Make sure that the static electricity in your body is discharged before touching electronic
components.
When the housing is open, EMC protection is limited.
Corrective maintenance work may only be performed by trained personnel.
• Depressurize the device and adjoining lines or containers before removing the device.
• Check whether hazardous materials are used as materials to be measured before opening
the device. Residual amounts of hazardous material may still be present in the device and
could escape when the device is opened.
• As far as provided in the scope of the operational responsibility, check the following items
through a regular inspection:
− the pressure-carrying walls / lining of the pressure device
− the measurement-related function
− the leak tightness
− the wear (corrosion)

Design and function
20 FV4000-VT4/VR4 / FS4000-ST4/SR4 D184B097U02
2 Design and function
2.1 Principles of measurement
2.1.1 Vortex flowmeter
The operating principle of the Vortex flowmeter is based on the Karman street. As the fluid flows
over and under the solid body, vortices are shed alternately above and below. The shedding of
these vortices due to the flow forms a vortex trail (Karman street).
G00680
12
Fig. 6: Principle of measurement, FV4000
1 Solid body 2 Piezo sensor
The frequency f of vortex shedding is proportional to the flow velocity v and inversely
proportional to the width of the solid body d:
d
v
Stf ×=
St, known as the Strouhal number, is a dimensionless number which has a decisive impact on
the quality of vortex flow measurement.
If the solid body is dimensioned appropriately, the Strouhal number St will be constant across a
very wide range of the Reynolds number Re (Fig. 2).
ϑ
×
=Dv Re
ϑ= Kinematic viscosity
D = Nominal size of meter tube