Vega VEGABAR 82 User manual

Operating Instructions
Pressure transmitter with ceramic
measuring cell
VEGABAR 82
Slave sensor for electronic differential pres-
sure
Document ID: 45050

2
Contents
VEGABAR 82 • Slave sensor for electronic dierential pressure
45050-EN-170522
Contents
1 About this document
1.1 Function ........................................................................................................................... 4
1.2 Target group..................................................................................................................... 4
1.3 Symbols used................................................................................................................... 4
2 For your safety
2.1 Authorised personnel ....................................................................................................... 5
2.2 Appropriate use................................................................................................................ 5
2.3 Warning about incorrect use............................................................................................. 5
2.4 General safety instructions............................................................................................... 5
2.5 EU conformity................................................................................................................... 6
2.6 Permissible process pressure .......................................................................................... 6
2.7 Installation and operation in the USA and Canada ........................................................... 6
2.8 Environmental instructions ............................................................................................... 6
3 Product description
3.1 Conguration.................................................................................................................... 7
3.2 Principle of operation........................................................................................................ 8
3.3 Supplementary cleaning procedures.............................................................................. 14
3.4 Packaging, transport and storage................................................................................... 14
3.5 Accessories and replacement parts ............................................................................... 15
4 Mounting
4.1 General instructions ....................................................................................................... 16
4.2 Ventilation and pressure compensation.......................................................................... 17
4.3 Combination Master - Slave ........................................................................................... 19
4.4 Level measurement........................................................................................................ 21
4.5 Dierential pressure measurement ................................................................................ 21
4.6 Interface measurement .................................................................................................. 22
4.7 Density measurement .................................................................................................... 23
4.8 Density-compensated level measurement ..................................................................... 24
4.9 External housing ............................................................................................................ 26
5 Connecting to power supply
5.1 Preparing the connection ............................................................................................... 27
5.2 Connecting..................................................................................................................... 28
5.3 Single chamber housing................................................................................................. 29
5.4 External housing with version IP 68 (25 bar)................................................................... 30
5.5 Connection example ...................................................................................................... 32
6 Set up with the display and adjustment module
6.1 Parameter adjustment - Quick setup .............................................................................. 33
6.2 Parameter adjustment - Extended adjustment................................................................ 33
7 Diagnosis, asset management and service
7.1 Maintenance .................................................................................................................. 46
7.2 Cleaning - hygienic connection with compression nut .................................................... 46
7.3 Rectify faults................................................................................................................... 47
7.4 Exchanging the electronics module................................................................................ 47
7.5 Exchange process assembly with version IP 68 (25 bar)................................................ 47
7.6 How to proceed if a repair is necessary.......................................................................... 49

3
Contents
VEGABAR 82 • Slave sensor for electronic dierential pressure
45050-EN-170522
8 Dismount
8.1 Dismounting steps.......................................................................................................... 50
8.2 Disposal ......................................................................................................................... 50
9 Supplement
9.1 Technical data ................................................................................................................ 51
9.2 Calculation of the total deviation..................................................................................... 61
9.3 Practical example........................................................................................................... 61
9.4 Dimensions .................................................................................................................... 64
9.5 Industrial property rights................................................................................................. 73
9.6 Trademark ...................................................................................................................... 73
Safety instructions for Ex areas
Take note of the Ex specic safety instructions for Ex applications.
These instructions are attached as documents to each instrument
with Ex approval and are part of the operating instructions manual.
Editing status: 2017-05-17

4
1 About this document
VEGABAR 82 • Slave sensor for electronic dierential pressure
45050-EN-170522
1 About this document
1.1 Function
This operating instructions manual provides all the information you
need for mounting, connection and setup as well as important instruc-
tions for maintenance, fault rectication, the exchange of parts and
the safety of the user. Please read this information before putting the
instrument into operation and keep this manual accessible in the im-
mediate vicinity of the device.
1.2 Target group
This operating instructions manual is directed to trained specialist
personnel. The contents of this manual should be made available to
these personnel and put into practice by them.
1.3 Symbols used
Information, tip, note
This symbol indicates helpful additional information.
Caution: If this warning is ignored, faults or malfunctions can result.
Warning: If this warning is ignored, injury to persons and/or serious
damage to the instrument can result.
Danger: If this warning is ignored, serious injury to persons and/or
destruction of the instrument can result.
Ex applications
This symbol indicates special instructions for Ex applications.
• List
The dot set in front indicates a list with no implied sequence.
→ Action
This arrow indicates a single action.
1 Sequence of actions
Numbers set in front indicate successive steps in a procedure.
Battery disposal
This symbol indicates special information about the disposal of bat-
teries and accumulators.

5
2 For your safety
VEGABAR 82 • Slave sensor for electronic dierential pressure
45050-EN-170522
2 For your safety
2.1 Authorised personnel
All operations described in this operating instructions manual must
be carried out only by trained specialist personnel authorised by the
plant operator.
During work on and with the device the required personal protective
equipment must always be worn.
2.2 Appropriate use
VEGABAR 82 is a slave sensor for electronic dierential pressure
measurement.
You can nd detailed information about the area of application in
chapter "Product description".
Operational reliability is ensured only if the instrument is properly
used according to the specications in the operating instructions
manual as well as possible supplementary instructions.
2.3 Warning about incorrect use
Inappropriate or incorrect use of this product can give rise to applica-
tion-specic hazards, e.g. vessel overll through incorrect mounting
or adjustment. Thus damage to property, to persons or environmental
contamination can be caused. Also the protective characteristics of
the instrument can be inuenced.
2.4 General safety instructions
This is a state-of-the-art instrument complying with all prevailing
regulations and directives. The instrument must only be operated in a
technically awless and reliable condition. The operator is responsi-
ble for the trouble-free operation of the instrument. When measuring
aggressive or corrosive media where a malfunction of the instrument
can cause a danger, the operator has to convince himself on the cor-
rect function of the instrument by taking suitable measures.
During the entire duration of use, the user is obliged to determine the
compliance of the necessary occupational safety measures with the
current valid rules and regulations and also take note of new regula-
tions.
The safety instructions in this operating instructions manual, the na-
tional installation standards as well as the valid safety regulations and
accident prevention rules must be observed by the user.
For safety and warranty reasons, any invasive work on the device
beyond that described in the operating instructions manual may be
carried out only by personnel authorised by the manufacturer. Arbi-
trary conversions or modications are explicitly forbidden. For safety
reasons, only the accessory specied by the manufacturer must be
used.

6
2 For your safety
VEGABAR 82 • Slave sensor for electronic dierential pressure
45050-EN-170522
To avoid any danger, the safety approval markings and safety tips on
the device must also be observed and their meaning looked up in this
operating instructions manual.
2.5 EU conformity
The device fulls the legal requirements of the applicable EU direc-
tives. By axing the CE marking, we conrm the conformity of the
instrument with these directives.
You can nd the EU conformity declaration on our website under
www.vega.com/downloads.
2.6 Permissible process pressure
For safety reasons, the instrument must only be operated within the
permissible process conditions. You can nd detailed information on
the process conditions in chapter "Technical data" as well as on the
type label.
The permissible process pressure range is specied on the type label
with "Process pressure", see chapter "Conguration". This applies
even if a measuring cell with a measuring range (order-related) higher
than the permissible pressure range of the process tting is installed.
A temperature derating, e.g. with anges, can limit the permissible
process pressure range.
2.7 Installation and operation in the USA and
Canada
This information is only valid for USA and Canada. Hence the follow-
ing text is only available in the English language.
Installations in the US shall comply with the relevant requirements of
the National Electrical Code (ANSI/NFPA 70).
Installations in Canada shall comply with the relevant requirements of
the Canadian Electrical Code
2.8 Environmental instructions
Protection of the environment is one of our most important duties.
That is why we have introduced an environment management system
with the goal of continuously improving company environmental pro-
tection. The environment management system is certied according
to DIN EN ISO 14001.
Please help us full this obligation by observing the environmental
instructions in this manual:
• Chapter "Packaging, transport and storage"
• Chapter "Disposal"

7
3 Product description
VEGABAR 82 • Slave sensor for electronic dierential pressure
45050-EN-170522
3 Product description
3.1 Conguration
The type label contains the most important data for identication and
use of the instrument:
2
1
13
14
12
10
11
5
3
6
4
7
8
9
Fig. 1: Layout of the type label (example)
1 Instrument type
2 Product code
3 Field for approvals
4 Power supply and signal output, electronics
5 Protection rating
6 Measuring range
7 Permissible process pressure
8 Material, wetted parts
9 Order number
10 Serial number of the instrument
11 Data matrix code for smartphone app
12 Symbol of the device protection class
13 ID numbers, instrument documentation
14 Reminder to observe the instrument documentation
The type label contains the serial number of the instrument. With it
you can nd the following instrument data on our homepage:
• Product code (HTML)
• Delivery date (HTML)
• Order-specic instrument features (HTML)
• Operating instructions and quick setup guide at the time of ship-
ment (PDF)
• Order-specic sensor data for an electronics exchange (XML)
• Test certicate (PDF) - optional
Go to "www.vega.com", "Instrument search (serial number)". Enter
the serial number.
Alternatively, you can access the data via your smartphone:
• Download the smartphone app "VEGA Tools" from the "Apple App
Store" or the "Google Play Store"
• Scan the Data Matrix code on the type label of the instrument or
• Enter the serial number manually in the app
Type label
Serial number - Instru-
ment search

8
3 Product description
VEGABAR 82 • Slave sensor for electronic dierential pressure
45050-EN-170522
This operating instructions manual applies to the following instrument
versions:
• Hardware from 1.0.0
• Software version from 1.0.0
Note:
You can nd the hardware and software version of the instrument as
follows:
• On the type plate of the electronics module
• In the adjustment menu under "Info"
The scope of delivery encompasses:
• Pressure transmitter VEGABAR 82 - Slave sensor
• Ready-made connection cable, unassembled cable gland
• Documentation
– Quick setup guide VEGABAR 82
– Characteristics test certicate
– Instructions for optional instrument features
– Ex-specic "Safety instructions" (with Ex versions)
– If necessary, further certicates
• DVD "DTM Collection", included therein
– PACTwa re
– DTM Collection
– Instrument master les (GSD) for Probus PA
– FDT certicates
Note:
Optional instrument features are also described in this operating
instructions manual. The respective scope of delivery results from the
order specication.
3.2 Principle of operation
The VEGABAR 82 slave sensor is combined with a sensor from the
instrument series for electronic dierential pressure measurement.
Scope of this operating
instructions manual
Scope of delivery
Electronicdierential
pressure

9
3 Product description
VEGABAR 82 • Slave sensor for electronic dierential pressure
45050-EN-170522
1
2
Fig. 2: Example, electronic dierential pressure for level measurement in pres-
surized vessel
1 VEGABAR 82
2 VEGABAR 82, slave sensor
The sensors are connected via a screened four-wire cable. The
measured value from the slave sensor is read in and factored into the
calculations. Power supply and parameter adjustment are carried out
through the master sensor.
Information:
The version "Relative pressure climate-compensated" is not suitable.
You can nd further information in chapter "Combination Master -
Slave " of this operating instructions.
The electronic dierential pressure measurement is suitable for the
measurement of the following process variables:
• Level
• Flow
• Dierential pressure
• Density
• Interface
• Level, density-compensated
VEGABAR 82 is suitable for applications in virtually all industries. It is
used for the measurement of the following pressure types.
Measured variables
Application area

10
3 Product description
VEGABAR 82 • Slave sensor for electronic dierential pressure
45050-EN-170522
• Gauge pressure
• Absolute pressure
• Vacuum
Measured products are gases, vapours and liquids.
Depending on the process tting and measurement setup, measured
products can be also viscous or contain abrasive substances.
The sensor element is the CERTEC®measuring cell with robust
ceramic diaphragm. The process pressure deects the ceramic
diaphragm and causes a capacitance change in the measuring cell.
This capacitance change is converted into an electrical signal and
outputted as measured value via the output signal.
16 µm
1
2
3
Fig. 3: Conguration of the CERTEC® measuring cell
1 Process diaphragm
2 Glass joint
3 Base element
The measuring cell is available in two sizes:
• CERTEC® (ø 28 mm) with large process and ange connections
as well as with measuring ranges 25 mbar and 100 bar
• Mini-CERTEC® (ø 17.5 mm) with small process ttings
A temperature sensor in the ceramic diaphragm of the CERTEC®or
on the ceramic base of the Mini-CERTEC®measuring cell detects the
actual process temperature. The temperature value is outputted via:
• The display and adjustment module
• The current output or the additional current output
• The digital signal output
Extreme process temperature jumps are also immediately detected
by the CERTEC® measuring cell. The values are compared with that
of an additional temperature measurement on the ceramic base body.
Within only a few measuring cycles the intelligent sensor electronics
compensates unavoidable measurement deviations due to tempera-
ture shocks. Such shocks cause (depending on the set damping) only
slight, brief changes to the output signal.
Measured products
Measuring system pres-
sure
Measuring system tem-
perature

11
3 Product description
VEGABAR 82 • Slave sensor for electronic dierential pressure
45050-EN-170522
The measuring cell design depends on the selected pressure type.
Relative pressure: the measuring cell is open to the atmosphere.
The ambient pressure is detected in the measuring cell and compen-
sated. It thus has no inuence on the measured value.
Absolute pressure: the measuring cell is evacuated and encapsu-
lated. The ambient pressure is not compensated and does hence
inuence the measured value.
The following presentations show examples for the installation of the
ceramic measuring cell into the process tting and the dierent seal
concepts.
The recessed installation is particularly suitable for applications with
gases, vapours and clear liquids. The measuring cell seal is posi-
tioned laterally as well as in addition in front.
1
2
5
6
3
4
Fig. 4: Recessed installation of the measuring cell (example: manometer con-
nection G½)
1 Measuring cell
2 Seal for the measuring cell
3 Additional, front seal for measuring cell
4 Diaphragm
5 Process tting
6 Seal for the process tting
The front-ush installation is particularly suitable for applications with
viscous and abrasive media and in case of buildup. The measuring
cell seal is positioned laterally.
Pressure types
Seal concepts
Recessed installation
Front-ushmountingwith
single seal

12
3 Product description
VEGABAR 82 • Slave sensor for electronic dierential pressure
45050-EN-170522
2
3
4
1
5
Fig. 5: Front-ush installation of the measuring cell (example: thread G1½)
1 Seal for the process tting
2 Measuring cell
3 Seal for the measuring cell
4 Process tting
5 Diaphragm
The completely front-ush mounting is particularly suitable for ap-
plications in the paper industry. The diaphragm is in the pulp ow, is
hence cleaned and protected against buildup.
1
2
3
4
5
Fig. 6: Front-ush installation of the measuring cell (example: M30 x 1.5)
1 Measuring cell
2 Seal for the measuring cell
3 Seal for the process tting
4 Process tting
5 Diaphragm
The front-ush installation is particularly suitable for applications with
viscous media. The additional, front sealing protects the glass joint
of the measuring cell against chemical attack and the measuring cell
electronics against diusion of aggressive gases from the process.
Completelyfront-ush
mounting with single seal
Front-ushmountingwith
double seal

13
3 Product description
VEGABAR 82 • Slave sensor for electronic dierential pressure
45050-EN-170522
1
2
3
4
5
Fig. 7: Front-ush installation of the measuring cell with double seal (example:
ange connection with extension)
1 Measuring cell
2 Seal for the measuring cell
3 Process tting
4 Additional, front seal for measuring cell
5 Diaphragm
The front-ush, hygienic installation of the measuring cell is particu-
larly suitable for food applications. The sealings are installed gap-free.
The form seal of the measuring cell protects also the glass joint.
1
2
3
4
5
Fig. 8: Hygienic installation of the measuring cell (example: hygienic tting with
compression nut)
1 Measuring cell
2 Form seal for the measuring cell
3 Gap-free seal for process tting
4 Process tting
5 Diaphragm
The front-ush, hygienic installation of the measuring cell acc. to 3A
is particularly suitable for food applications. The sealings are installed
gap-free. The additional front sealing for the measuring cell protects
also the glass joint. A hole in the process tting is used for leakage
detection.
Installation in hygienic
tting
Installation in hygienic
ttingacc.to3-A

14
3 Product description
VEGABAR 82 • Slave sensor for electronic dierential pressure
45050-EN-170522
1
6
2
3
4
5
Fig. 9: Hygienic installation of the measuring cell acc. to 3-A (example: Clamp
connection)
1 Measuring cell
2 Seal for the measuring cell
3 Process tting
4 Additional, front seal for measuring cell
5 Diaphragm
5 Hole for leakage detection
3.3 Supplementary cleaning procedures
The VEGABAR 82 is also available in the version "Oil, grease and
silicone-free". These instruments have passed through a special
cleaning procedure to remove oil, grease and paint-wetting impair-
ment substances (PWIS).
The cleaning is carried out on all wetted parts as well as on surfaces
accessible from outside. To keep the purity level, the instruments are
immediately packed in plastic foil after the cleaning process. The
purity level remains as long as the instrument is kept in the closed
original packaging.
Caution:
The VEGABAR 82 in this version may not be used in oxygen ap-
plications. For this purpose, instruments are available in the special
version "Oil and grease-free for oxygen applications".
3.4 Packaging, transport and storage
Your instrument was protected by packaging during transport. Its
capacity to handle normal loads during transport is assured by a test
based on ISO 4180.
The packaging of standard instruments consists of environment-
friendly, recyclable cardboard. For special versions, PE foam or PE
foil is also used. Dispose of the packaging material via specialised
recycling companies.
Transport must be carried out in due consideration of the notes on the
transport packaging. Nonobservance of these instructions can cause
damage to the device.
The delivery must be checked for completeness and possible transit
damage immediately at receipt. Ascertained transit damage or con-
cealed defects must be appropriately dealt with.
Packaging
Transport
Transport inspection

15
3 Product description
VEGABAR 82 • Slave sensor for electronic dierential pressure
45050-EN-170522
Up to the time of installation, the packages must be left closed and
stored according to the orientation and storage markings on the
outside.
Unless otherwise indicated, the packages must be stored only under
the following conditions:
• Not in the open
• Dry and dust free
• Not exposed to corrosive media
• Protected against solar radiation
• Avoiding mechanical shock and vibration
• Storage and transport temperature see chapter "Supplement -
Technical data - Ambient conditions"
• Relative humidity 20 … 85 %
With an instrument weight of more than 18 kg (39.68 lbs) suitable and
approved equipment must be used for lifting and carrying.
3.5 Accessories and replacement parts
The protective cover protects the sensor housing against soiling and
intense heat from solar radiation.
You will nd additional information in the supplementary instructions
manual "Protective cover" (Document-ID 34296).
Screwed anges are available in dierent versions according to the
following standards: DIN 2501, EN 1092-1, BS 10, ASME B 16.5,
JIS B 2210-1984, GOST 12821-80.
You can nd additional information in the supplementary instructions
manual "Flanges according to DIN-EN-ASME-JIS".
Welded sockets are used to connect the sensors to the process.
You can nd further information in the supplementary instructions
"Welded socket VEGABAR series 80" (Document-ID 48094).
The electronics module VEGABAR series 80 is a replacement part
for pressure transmitters of VEGABAR series 80. There is a dierent
version available for each type of signal output.
You can nd further information in the operating instructions "Elec-
tronics module VEGABAR series 80" (Document-ID 45054).
Storage
Storage and transport
temperature
Lifting and carrying
Protective cover
Flanges
Welded socket
Electronics module

16
4 Mounting
VEGABAR 82 • Slave sensor for electronic dierential pressure
45050-EN-170522
4 Mounting
4.1 General instructions
Make sure before mounting that all parts of the instrument exposed to
the process are suitable for the existing process conditions.
These are mainly:
• Active measuring component
• Process tting
• Process seal
Process conditions in particular are:
• Process pressure
• Process temperature
• Chemical properties of the medium
• Abrasion and mechanical inuences
You can nd detailed information on the process conditions in chapter
"Technical data" as well as on the type label.
The instrument is suitable for standard and extended ambient condi-
tions acc. to DIN/EN/IEC/ANSI/ISA/UL/CSA 61010-1.
Protect your instrument against moisture ingress through the following
measures:
• Use the recommended cable (see chapter "Connecting to power
supply")
• Tighten the cable gland
• When mounting horizontally, turn the housing so that the cable
gland points downward
• Loop the connection cable downward in front of the cable gland
This applies mainly to outdoor installations, in areas where high
humidity is expected (e.g. through cleaning processes) and on cooled
or heated vessels.
To maintain the housing protection, make sure that the housing lid is
closed during operation and locked, if necessary.
Make sure that the degree of contamination specied in chapter
"Technical data" meets the existing ambient conditions.
On instruments with threaded process tting, the hexagon must be
tightened with a suitable wrench. For the proper wrench size see
chapter "Dimensions".
Warning:
The housing must not be used to screw the instrument in! Applying
tightening force can damage internal parts of the housing.
If there is strong vibration at the mounting location, the instrument
version with external housing should be used. See chapter "External
housing".
Suitability for the process
conditions
Suitability for the ambient
conditions
Protection against mois-
ture
Screwing in
Vibrations

17
4 Mounting
VEGABAR 82 • Slave sensor for electronic dierential pressure
45050-EN-170522
Higher process temperatures often mean also higher ambient
temperatures. Make sure that the upper temperature limits stated in
chapter "Technical data" for the environment of the electronics hous-
ing and connection cable are not exceeded.
1
2
Fig. 10: Temperature ranges
1 Process temperature
2 Ambient temperature
4.2 Ventilation and pressure compensation
Ventilation and pressure compensation are carried out with
VEGABAR 82 via a lter element. It is air permeable and moisture-
blocking.
Caution:
The lter element causes a time-delayed pressure compensation.
When quickly opening/closing the housing cover, the measured value
can change for approx. 5 s by up to 15 mbar.
For eective ventilation, the lter element must always be free of
buildup.
Caution:
Do not use a high-pressure cleaner. The lter element could be dam-
aged, which would allow moisture into the housing.
The following paragraphs describe how the lter element is arranged
in the dierent instrument versions.
The lter element is mounted into the electronics housing. It has the
following functions:
• Ventilation of the electronics housing
• Atmospheric pressure compensation (with relative pressure meas-
uring ranges)
→ Turn the housing so that the lter element points downward after
the instrument is installed. This provides better protection against
buildup.
Temperature limits
Filter elements
Instruments in non-Ex
and Ex-ia version

18
4 Mounting
VEGABAR 82 • Slave sensor for electronic dierential pressure
45050-EN-170522
1 2 3
4 4 4
Fig. 11: Position of the lter element - non-Ex, Ex-ia version
1 Plastic, stainless steel housing (precision casting)
2 Aluminium housing
3 Stainless steel housing (electropolished)
4 Filter element
With the following instruments a blind plug is installed instead of the
lter element:
• Instruments in protection IP 66/IP 68 (1 bar) - ventilation via capil-
laries in non-detachable cable
• Instruments with absolute pressure
The lter element is integrated in the process assembly. It is located in
a rotatable metal ring and has the following function:
• Atmospheric pressure compensation (with relative pressure meas-
uring ranges)
→ Turn the metal ring in such a way that the lter element points
downward after installation of the instrument. This provides better
protection against buildup.
1
2
Fig. 12: Position of the lter element - Ex-d version
1 Rotatable metal ring
2 Filter element
Instruments with absolute pressure have a blind plug mounted
instead of the lter element.
The lter element is mounted into the electronics housing. It has the
following functions:
• Ventilation of the electronics housing
→ Turn the housing so that the lter element points downward after
the instrument is installed. This provides better protection against
buildup.
Instruments in Ex-d ver-
sion
Instruments with Second
Line of Defense

19
4 Mounting
VEGABAR 82 • Slave sensor for electronic dierential pressure
45050-EN-170522
The process assembly of instruments with Second Line of Defense
(gastight leadthrough) is completely encapsulated. An absolute pres-
sure measuring cell is used so that no ventilation is required.
1
2
Fig. 13: Position of the lter element - gastight leadthrough
1 Filter element
The lter element is mounted into the electronics housing. It has the
following functions:
• Ventilation of the electronics housing
• Atmospheric pressure compensation (with relative pressure meas-
uring ranges)
→ Turn the housing so that the lter element points downward after
the instrument is installed. This provides better protection against
buildup.
1
Fig. 14: Position of the lter element - IP 69K version
1 Filter element
Instruments with absolute pressure have a blind plug mounted
instead of the lter element.
4.3 Combination Master - Slave
In principle, any sensor combination within the instrument series is
allowed. The following requirements must be fullled:
• Conguration, Master sensor suitable for electronic dierential
pressure
• Pressure type is identical for both sensors, i.e. relative pressure/
relative pressure or absolute pressure/absolute pressure
• Master sensor measures the higher pressure
• Measurement setup as shown in the following chapters
Instruments in IP 69K
version

20
4 Mounting
VEGABAR 82 • Slave sensor for electronic dierential pressure
45050-EN-170522
The measuring range of each sensor is selected such that it ts the
measuring loop. For this, the max. recommended turn down must be
noted. See chapter "Technical data". It is absolutely necessary the the
measuring ranges of Master and Slave correspond.
Measurement result = Measured value of Master (total pres-
sure) - measured value of Slave (static pressure)
Depending on the application, individual combinations can result, see
following examples:
Data
Application: Level measurement
Medium: Water
Vessel height: 12 m, hydrostatic pressure = 12 m x 1000 kg/m3x
9.81 m/s2 = 117.7 kPa = 1.18 bar
Superimposed pressure: 1 bar
Total pressure: 1.18 bar + 1 bar = 2.18 bar
Instrument selection
Nominal measuring range Master: 2.5 bar
Nominal measuring range Slave: 1 bar
Turn Down: 2.5 bar/1.18 bar = 2.1 : 1
Data
Application: Level measurement
Medium: Water
Vessel height: 500 mm, hydrostatic pressure = 0.50 m x 1000 kg/m3x
9.81 m/s2 = 4.9 kPa = 0.049 bar
Superimposed pressure: 350 mbar = 0.35 bar
Total pressure: 0.049 bar + 0.35 bar = 0.399 bar
Instrument selection
Nominal measuring range Master: 0.4 bar
Nominal measuring range Slave: 0.4 bar
Turn Down: 0.4 bar /0.049 bar = 8.2 : 1
Data
Application: Dierential pressure measurement
Medium: Gas
Static pressure: 0.8 bar
Dierential pressure on orice: 50 mbar bar = 0.050 bar
Total pressure: 0.8 bar bar + 0.05 bar = 0.85 bar
Instrument selection
Nominal measuring range Master: 1 bar
Nominal measuring range Slave: 1 bar
Turn Down: 1 bar/0.050 bar = 20 : 1
Example - large vessel
Example - small vessel
Example-oricein
pipeline