Vega VEGAPULS 61 User manual

Operating Instructions
Radar sensor for continuous level
measurement of liquids
VEGAPULS 61
Modbus and Levelmaster protocol
Approval according to LPR radio standard
Document ID: 41717

2
Contents
VEGAPULS 61 • Modbus and Levelmaster protocol
41717-EN-160224
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 CE conformity................................................................................................................... 6
2.6 NAMUR recommendations .............................................................................................. 6
2.7 Radio license for Europe .................................................................................................. 6
2.8 Radio license for USA/Canada......................................................................................... 7
2.9 Environmental instructions ............................................................................................... 7
3 Product description
3.1 Conguration.................................................................................................................... 8
3.2 Principle of operation........................................................................................................ 9
3.3 Packaging, transport and storage..................................................................................... 9
3.4 Accessories and replacement parts ............................................................................... 10
4 Mounting
4.1 General instructions ....................................................................................................... 12
4.2 Collaroradapterange.................................................................................................. 13
4.3 Mounting preparations, mounting strap.......................................................................... 13
4.4 Mounting instructions ..................................................................................................... 14
4.5 Measurement setup - Pipes ........................................................................................... 20
4.6 Measurement setup - Flow............................................................................................. 25
5 Connecting to power supply and bus system
5.1 Preparing the connection ............................................................................................... 27
5.2 Connecting..................................................................................................................... 28
5.3 Wiring plan, double chamber housing ............................................................................ 30
5.4 Double chamber housing with DISADAPT ..................................................................... 31
5.5 Switch-on phase............................................................................................................. 32
6 Set up the sensor with the display and adjustment module
6.1 Adjustment volume......................................................................................................... 33
6.2 Insert display and adjustment module............................................................................ 33
6.3 Adjustment system......................................................................................................... 34
6.4 Measured value indication - Selection national language............................................... 35
6.5 Parameter adjustment .................................................................................................... 35
6.6 Saving the parameter adjustment data........................................................................... 53
7 Setting up sensor and Modbus interface with PACTware
7.1 Connect the PC.............................................................................................................. 54
7.2 Parameter adjustment .................................................................................................... 55
7.3 Saving the parameter adjustment data........................................................................... 57
8 Diagnosis, asset management and service
8.1 Maintenance .................................................................................................................. 58

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Contents
VEGAPULS 61 • Modbus and Levelmaster protocol
41717-EN-160224
8.2 Measured value and event memory ............................................................................... 58
8.3 Asset Management function........................................................................................... 59
8.4 Rectify faults................................................................................................................... 62
8.5 Exchanging the electronics module................................................................................ 65
8.6 Software update ............................................................................................................. 66
8.7 How to proceed if a repair is necessary.......................................................................... 66
9 Dismount
9.1 Dismounting steps.......................................................................................................... 67
9.2 Disposal ......................................................................................................................... 67
10 Supplement
10.1 Technical data ................................................................................................................ 68
10.2 Basics Modbus............................................................................................................... 73
10.3 Modbus register ............................................................................................................. 75
10.4 Modbus RTU commands ............................................................................................... 77
10.5 Levelmaster commands ................................................................................................. 80
10.6 CongurationoftypicalModbushosts ........................................................................... 84
10.7 Radio astronomy stations............................................................................................... 88
10.8 Dimensions .................................................................................................................... 89
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: 2016-01-29

4
1 About this document
VEGAPULS 61 • Modbus and Levelmaster protocol
41717-EN-160224
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andfaultrectication.Pleasereadthisinforma-
tion before putting the instrument into operation and keep this manual
accessible in the immediate 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
VEGAPULS 61 • Modbus and Levelmaster protocol
41717-EN-160224
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
VEGAPULS 61 is a sensor for continuous level 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 the instrument can give rise to
application-specichazards,e.g.vesseloverllordamagetosystem
components through incorrect mounting or adjustment. Also the pro-
tective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 guidelines. The instrument must only be operated in a
technicallyawlessandreliablecondition.Theoperatorisresponsible
for the trouble-free operation of the instrument.
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.
The safety approval markings and safety tips on the device must also
be observed.
Depending on the instrument version, the emitting frequencies are in
the C, K or W band range.The low emitting frequencies are far below
the internationally approved limit values. When used correctly, the
device poses no danger to health.

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2 For your safety
VEGAPULS 61 • Modbus and Levelmaster protocol
41717-EN-160224
2.5 CE conformity
ThedevicefulllsthelegalrequirementsoftheapplicableECguide-
lines.ByaxingtheCEmarking,weconrmsuccessfultestingofthe
product.
YoucanndtheCECerticateofConformityinthedownloadsection
of our homepage.
Electromagnetic compatibility
Instruments with plastic housing are designed for use in an industrial
environment. Nevertheless, electromagnetic interference from electri-
cal conductors and radiated emissions must be taken into account,
as is usual with class A instruments according to EN 61326-1. If the
instrumentisusedinadierentenvironment,theelectromagnetic
compatibility to other instruments must be ensured by suitable meas-
ures.
2.6 NAMUR recommendations
NAMUR is the automation technology user association in the process
industry in Germany.The published NAMUR recommendations are
acceptedasthestandardineldinstrumentation.
ThedevicefulllstherequirementsofthefollowingNAMURrecom-
mendations:
• NE 21 – Electromagnetic compatibility of equipment
• NE53–Compatibilityofelddevicesanddisplay/adjustment
components
• NE107–Self-monitoringanddiagnosisofelddevices
For further information see www.namur.de.
2.7 Radio license for Europe
The instrument meets the LPR (Level Probing Radar) radio standard
EN 302729-1/2.
It is approved for unrestricted use inside and outside of closed ves-
sels in countries of the EU and EFTA that have implemented this
standard:
Austria, Belgium, Bulgaria, Germany, Denmark, Estonia, France,
Greece, Great Britain, Ireland, Island, Italy, Liechtenstein, Lithuania,
Latvia, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania,Sweden,Switzerland,Slovakia,Slovenia,Spain,Czech
Republik and Cyprus.
NotincludedintheCEconrmitydeclarationarethecountriesFin-
land and Hungary implementing this radio standard at a later date.
For operation outside of closed vessels, the following conditions must
befullled:
• Theinstallationmustbecarriedoutbytrainedqualiedpersonnel
• The instrument must be stationary mounted and the antenna
directed vertically downward

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2 For your safety
VEGAPULS 61 • Modbus and Levelmaster protocol
41717-EN-160224
• The mounting location must be at least 4 km away from radio
astronomy stations, unless special permission was granted by the
responsible national approval authority
• When installed within 4 to 40 km of a radio astronomy station,
the instrument must not be mounted higher than 15 m above the
ground.
Youcanndalistoftherespectiveradioastronomystationsinchap-
ter "Supplement".
2.8 Radio license for USA/Canada
The instrument is in conformity with part 15 of the FCC regulations.
Take note of the following two regulations:
• This device may not cause interference, and
• This device must accept any interference, including interference
that may cause undesired operation of the device
Modicationsnotexpresslyapprovedbythemanufacturerwillleadto
expiry of the operating licence according to FCC/IC.
The instrument is in conformity with RSS-210 of the IC regulations.
The instrument may only be used in closed vessels made of metal,
concrete,orbre-reinforcedplastic.
2.9 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llthisobligationbyobservingtheenvironmental
instructions in this manual:
• Chapter "Packaging, transport and storage"
• Chapter "Disposal"

8
3 Product description
VEGAPULS 61 • Modbus and Levelmaster protocol
41717-EN-160224
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
15
13
14
12
11
5
3
6
4
7
8
10
9
Fig. 1: Layout of the type label (example)
1 Instrument type
2 Product code
3 Approvals
4 Power supply and signal output, electronics
5 Protection rating
6 Measuring range
7 Process and ambient temperature, process pressure
8 Material, wetted parts
9 Hardware and software version
10 Order number
11 Serial number of the instrument
12 Data-Matrix-Code for smartphone app
13 Symbol of the device protection class
14 ID number, instrument documentation
15 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 "VEGA Tools" and "Instrument search". 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

9
3 Product description
VEGAPULS 61 • Modbus and Levelmaster protocol
41717-EN-160224
This operating instructions manual applies to the following instrument
versions:
• Sensor electronics: Hardware from 1.0.0, software from 4.4.0
• Modbus electronics: Hardware from 1.0.0, software from 4.4.0
The scope of delivery encompasses:
• Radar sensor
• Mountingstrapwithxingmaterial(optional)
• Documentation
– Quick setup guide VEGAPULS 61
– Instructions for optional instrument features
– Ex-specic"Safety instructions" (with Ex versions)
– Ifnecessary,furthercerticates
• DVD "Software", included therein
– PACTware/DTM Collection
– Driver software
Information:
In the operating instructions manual, the optional instrument features
are described.The respective scope of delivery results from the order
specication.
3.2 Principle of operation
The VEGAPULS 61 is a radar sensor for continuous level measure-
ment of liquids under simple process conditions.
The instrument is ideal also for all applications in the water and waste
water industry. It is particularly suitable for level measurement in water
treatment,inpumpstationsaswellasstormwateroverowtanks,for
owmeasurementinopenumesandforgaugemeasurement.
The antenna of the radar sensor emits short radar pulses with a
durationofapprox.1ns.Thesepulsesarereectedbytheproduct
and received by the antenna as echoes.The transit time of the radar
pulses from emission to reception is proportional to the distance and
hence to the level.The determined level is converted into an appropri-
ate output signal and outputted as measured value.
3.3 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.
Scope of this operating
instructions manual
Scope of delivery
Application area
Functional principle
Packaging
Transport

10
3 Product description
VEGAPULS 61 • Modbus and Levelmaster protocol
41717-EN-160224
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.
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 %
3.4 Accessories and replacement parts
The display and adjustment module PLICSCOM is used for measured
value indication, adjustment and diagnosis. It can be inserted into the
sensor and removed at any time.
Youcanndfurtherinformationintheoperatinginstructions"Display
and adjustment module PLICSCOM" (Document-ID 27835).
The interface adapter VEGACONNECT enables the connection of
communication-capable instruments to the USB interface of a PC. For
parameter adjustment of these instruments, the adjustment software
PACTware with VEGA-DTM is required.
Youcanndfurtherinformationintheoperatinginstructions"Interface
adapter VEGACONNECT" (Document-ID 32628).
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".
Electronics module "VEGAPULS series 60" is a replacement part for
radarsensorsofVEGAPULSseries60.Adierentversionisavailable
for each type of signal output.
Youcanndfurtherinformationintheoperatinginstructions"Elec-
tronics module VEGAPULS series 60" (Document-ID 36801).
Transport inspection
Storage
Storage and transport
temperature
PLICSCOM
VEGACONNECT
Protective cap
Flanges
Electronics module

11
3 Product description
VEGAPULS 61 • Modbus and Levelmaster protocol
41717-EN-160224
The supplementary electronics is a replacement part for sensors with
signal output Modbus.
Youcanndfurtherinformationintheoperatinginstructions"Supple-
mentary electronics Modbus" (Document-ID 41864).
The antenna impedance cone is a replacement part used for optimum
transmission of microwaves and for sealing against the process.
Youndfurtherinformationintheoperatinginstructions"Antenna
impedance cone VEGAPULS 62 and 68" (Document-ID 31381).
Supplementary electron-
ics Modbus
Antenna impedance cone

12
4 Mounting
VEGAPULS 61 • Modbus and Levelmaster protocol
41717-EN-160224
4 Mounting
4.1 General instructions
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.
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 humidity is
expected (e.g. through cleaning processes) and on cooled or heated
vessels.
Make sure 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 are particularly:
• 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.
Metric threads
In the case of instrument housings with metric thread, the cable
glands are screwed in at the factory.They are sealed with plastic
plugs as transport protection.
You have to remove these plugs before electrical connection.
NPT thread
In the case of instrument housings with self-sealing NPT threads, it is
not possible to have the cable entries screwed in at the factory. The
free openings for the cable glands are therefore covered with red dust
protection caps as transport protection.The dust protection caps do
notprovidesucientprotectionagainstmoisture.
Screwing in
Protection against mois-
ture
Suitability for the process
conditions
Cable glands

13
4 Mounting
VEGAPULS 61 • Modbus and Levelmaster protocol
41717-EN-160224
Prior to setup you have to replace these protective caps with ap-
proved cable glands or close the openings with suitable blind plugs.
4.2 Collaroradapterange
Formountingtheinstrumentonasocket,acombicompressionange
forDN80(ASME3"orJIS80)isalsoavailableforretrotting.Option-
ally,theinstrumentcanbealsoequippedwithanadapterangefrom
DN 100 (ASME 4" or JIS 100).
With the housing versions plastic, aluminium single chamber and
stainlesssteel,thecollarangecanbeplaceddirectlyoverthehous-
ing. With the aluminium double chamber housing, retroactive mount-
inginthiswayisnotpossible-themountingtypemustbespecied
with the order.
Youcannddrawingsofthesemountingoptionsinchapter"Dimen-
sions".
Fig. 2: Flange mounting of the radar sensor
4.3 Mounting preparations, mounting strap
The mounting strap enables simple mounting on the vessel wall or
silo top. It is suitable for wall, ceiling or boom mounting. Especially in
openvesselsthisisaveryeasyandeectivewaytoalignthesensor
to the bulk solid surface.
The strap is supplied unassembled and must be screwed to the
sensor before setup with three hexagon socket screws M5 x 10 and
spring washers. Max. torque, see chapter "Technical data". Required
tools:Allenwrenchsize4.
There are two ways to screw the strap onto the sensor. Depending
on the selected version, the sensors can be swivelled in the strap as
follows:

14
4 Mounting
VEGAPULS 61 • Modbus and Levelmaster protocol
41717-EN-160224
• Single chamber housing
– Angleofinclination180°,innitelyvariable
– Angle of inclination in three steps 0°, 90° and 180°
• Double chamber housing
– Angleofinclination90°,innitelyvariable
– Angle of inclination in two steps 0° and 90°
Fig. 3: Adjustment of the angle of inclination
Fig. 4: Turning by fastening in the centre
4.4 Mounting instructions
For tight installation of the version with plastic horn antenna with com-
pressionoradapterange,thefollowingconditionsmustbefullled:
1. Usesuitableatseal,e.g.ofEPDMwithShorehardness25or50
2. Makesurethenumberofangescrewscorrespondstothenum-
berofangeholes
3. Tighten all screws with the torque stated in the technical data
The emitted radar impulses of the radar sensor are electromagnetic
waves. The polarisation is the direction of the electrical wave compo-
nent.Byturningtheinstrumentintheconnectionangeormounting
boss,thepolarisationcanbeusedtoreducetheeectsoffalse
echoes.
Thepositionofthepolarisationismarkedontheprocessttingofthe
instrument.
Tight installation of the
plastic horn antenna
Polarisation

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4 Mounting
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12
Fig. 5: Position of the polarisation
1 Marking with version with plastic horn antenna
2 Marking with version with encapsulated antenna system
When mounting the sensor, keep a distance of at least 200 mm
(7.874 in) to the vessel wall. If the sensor is installed in the center of
dished or round vessel tops, multiple echoes can arise.These can,
however, be suppressed by an appropriate adjustment (see chapter
"Setup").
If you cannot maintain this distance, you should carry out a false
signal storage during setup.This applies particularly if buildup on the
vessel wall is expected. In such cases, we recommend repeating the
false signal storage at a later date with existing buildup.
> 200 mm
(7.87
")
Fig. 6: Mounting of the radar sensor on round vessel tops
In vessels with conical bottom it can be advantageous to mount the
sensor in the center of the vessel, as measurement is then possible
down to the lowest point of the vessel bottom.
Installation position

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Fig. 7: Mounting of the radar sensor on vessels with conical bottom
Donotmounttheinstrumentsinorabovethellingstream.Makesure
thatyoudetecttheproductsurface,nottheinowingproduct.
Fig. 8: Mounting of the radar sensor with inowing medium
The socket piece should be dimensioned in such a way that the an-
tenna end protrudes at least 10 mm (0.4 in) out of the socket.
Inowingmedium
Socket with encapsulated
antenna system

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ca. 10 mm
Fig. 9: Recommended socket mounting
Ifthereectivepropertiesofthemediumaregood,youcanmount
VEGAPULS 61 on sockets which are higher than the length of the
antenna.Youwillndrecommendedvaluesforsocketheightsinthe
following illustration.The socket end should be smooth and burr-free,
if possible also rounded. After installation you must carry out a false
echo storage.
d
h
Fig. 10: Deviating socket dimensions
The below charts specify the max. socket length h depending on the
diameter d.
Socket diameter d Socket length h
40 mm ≤200mm
50 mm ≤250mm
80 mm ≤300mm
100 mm ≤400mm
150 mm ≤500mm
Socket diameter d Socket length h
1½" ≤7.9in
2" ≤9.9in
3" ≤11.8in

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Socket diameter d Socket length h
4" ≤15.8in
6" ≤19.7in
AcorrespondingcollarangeforDN80(ASME3"orJIS80)aswell
asasuitableadapterangeareavailableformountingVEGAPULS
61.
With the housing versions plastic, aluminium single chamber and
stainlesssteel,thecollarangecanbeplaceddirectlyoverthehous-
ing. With the aluminium double chamber housing, retroactive mount-
inginthiswayisnotpossible-themountingtypemustbespecied
with the order.
Information:
The mounting socket should be as short as possible and its end
rounded.This reduces false echoes from the vessel mounting socket.
Fig. 11: Recommended socket mounting
Ifthemediumhasgoodreectiveproperties,VEGAPULS61can
also be mounted on a longer socket piece. Recommended values
forsocketheightsarespeciedinthefollowingillustration.Youmust
carry out a false echo storage afterwards.
d
h
The below charts specify the max. socket length h depending on the
diameter d.
Socket diameter d Socket length h
80 mm ≤300mm
Socket with plastic horn
antenna

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Socket diameter d Socket length h
100 mm ≤400mm
150 mm ≤500mm
Socket diameter d Socket length h
3" ≤11.8in
4" ≤15.8in
6" ≤19.7in
In liquids, direct the sensor as perpendicular as possible to the prod-
uct surface to achieve optimum measurement results.
Fig. 13: Alignment in liquids
The mounting location of the radar sensor should be a place where no
otherequipmentorxturescrossthepathoftheradarsignals.
Vessel installations, such as e.g. ladders, limit switches, heating spi-
rals, struts, etc., can cause false echoes and impair the useful echo.
Make sure when planning your measuring point that the radar sensor
has a "clear view" to the measured product.
In case of existing vessel installations, a false echo storage should be
carried out during setup.
If large vessel installations such as struts or supports cause false
echoes, these can be attenuated through supplementary measures.
Small,inclinedsheetmetalbaesabovetheinstallationsscatterthe
radarsignalsandpreventdirectinterferingreections.
Fig. 14: Cover at, large-area proles with deectors
If there are agitators in the vessel, a false signal storage should be
carried out with the agitators in motion.This ensures that the interfer-
ingreectionsfromtheagitatorsaresavedwiththebladesindierent
positions.
Sensor orientation
Vessel installations
Agitators

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Fig. 15: Agitators
Throughtheactionoflling,stirringandotherprocessesinthevessel,
compact foam can form on the product surface, damping the emitted
signals considerably.
If foams are causing measurement errors, the biggest possible radar
antennas, the electronics with increased sensitivity or low frequency
radar sensors (C band) should be used.
As an alternative, sensors with guided microwave can be used. These
areunaectedbyfoamgenerationandarebestsuitedforsuchap-
plications.
4.5 Measurement setup - Pipes
Byusingasurgepipeinthevessel,theinuenceofvesselinstalla-
tions and turbulence can be excluded. Under these prerequisites, the
measurementofproductswithlowdielectricvalues(εrvalue≤1.6)is
possible.
Note the following illustrations and instructions for measurement in a
surge pipe.
Information:
Measurement in a surge pipe is not recommended for extremely
adhesive products.
Foam generation
Measurement in a surge
pipe