Vega VEGAFLEX 81 User manual

Operating Instructions
TDR sensor for continuous level and
interface measurement of liquids
VEGAFLEX 81
Modbus and Levelmaster protocol
Coax probe
Document ID: 42283

2
Contents
VEGAFLEX 81 • Modbus and Levelmaster protocol
42283-EN-140430
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................................................................................................................... 5
2.6 NAMUR recommendations .............................................................................................. 6
2.7 Environmental instructions ............................................................................................... 6
3 Product description
3.1 Conguration.................................................................................................................... 7
3.2 Principle of operation........................................................................................................ 9
3.3 Packaging, transport and storage................................................................................... 11
3.4 Accessories and replacement parts ............................................................................... 11
4 Mounting
4.1 General instructions ....................................................................................................... 14
4.2 Mounting instructions ..................................................................................................... 15
5 Connecting to power supply
5.1 Preparing the connection ............................................................................................... 18
5.2 Connecting..................................................................................................................... 18
5.3 Wiring plan, double chamber housing ............................................................................ 21
5.4 Double chamber housing with DIS-ADAPT .................................................................... 22
5.5 Supplementary electronics............................................................................................. 23
5.6 Switch-on phase............................................................................................................. 23
6 Set up the sensor with the display and adjustment module
6.1 Adjustment volume......................................................................................................... 25
6.2 Insert display and adjustment module............................................................................ 25
6.3 Adjustment system......................................................................................................... 26
6.4 Parameter adjustment - Quick setup .............................................................................. 27
6.5 Parameter adjustment - Extended adjustment................................................................ 29
6.6 Saving the parameter adjustment data........................................................................... 48
7 Setting up sensor and Modbus interface with PACTware
7.1 Connect the PC.............................................................................................................. 50
7.2 Parameter adjustment with PACTware............................................................................ 51
7.3 Set up with the quick setup............................................................................................. 52
7.4 Saving the parameter adjustment data........................................................................... 57
8 Diagnostics and service
8.1 Maintenance .................................................................................................................. 58
8.2 Diagnosis memory ......................................................................................................... 58
8.3 Status messages............................................................................................................ 59
8.4 Rectify faults................................................................................................................... 63
8.5 Exchanging the electronics module................................................................................ 66

3
Contents
VEGAFLEX 81 • Modbus and Levelmaster protocol
42283-EN-140430
8.6 Software update............................................................................................................. 67
8.7 How to proceed if a repair is needed.............................................................................. 67
9 Dismounting
9.1 Dismounting steps.......................................................................................................... 68
9.2 Disposal ......................................................................................................................... 68
10 Supplement
10.1 Technical data ................................................................................................................ 69
10.2 Basics Modbus............................................................................................................... 77
10.3 Modbus register ............................................................................................................. 79
10.4 Modbus RTU commands ............................................................................................... 81
10.5 Levelmaster commands ................................................................................................. 84
10.6 CongurationoftypicalModbushosts ........................................................................... 88
10.7 Dimensions .................................................................................................................... 92
Safety instructions for Ex areas
PleasenotetheEx-specicsafetyinformationforinstallationandop-
eration in Ex areas. These safety instructions are part of the operating
instructions manual and come with the Ex-approved instruments.
Editing status: 2014-03-31

4
1 About this document
VEGAFLEX 81 • Modbus and Levelmaster protocol
42283-EN-140430
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
VEGAFLEX 81 • Modbus and Levelmaster protocol
42283-EN-140430
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
VEGAFLEX 81 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.
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.
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.

6
2 For your safety
VEGAFLEX 81 • Modbus and Levelmaster protocol
42283-EN-140430
Electromagnetic compatibility
Instruments in four-wire or Ex-d-ia version are designed for use in an
industrial environment. Nevertheless, electromagnetic interference
from electrical 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electromag-
netic compatibility to other instruments must be ensured by suitable
measures.
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 43 – Signal level for malfunction information from measuring
transducers
•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 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"

7
3 Product description
VEGAFLEX 81 • Modbus and Levelmaster protocol
42283-EN-140430
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
15
16
12
11
5
3
6
4
7
8
9
10
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 Probe length
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 Symbol of the device protection class
13 ID numbers, instrument documentation
14 Reminder to observe the instrument documentation
15 NotiedauthorityforCEmarking
16 Approval directives
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"
Type label
Serial number - Instru-
ment search

8
3 Product description
VEGAFLEX 81 • Modbus and Levelmaster protocol
42283-EN-140430
•Scan the Data Matrix code on the type label of the instrument or
•Enter the serial number manually in the app
Theinstrumentcontainstwodierentelectronicsinitshousingcham-
bers:
•The Modbus electronics for power supply and communication with
the Modbus-RTU
•The sensor electronics for the actual measuring tasks
2
1
Fig. 2: Position of Modbus and sensor electronics
1 Modbus electronics
2 Sensor electronics
This operating instructions manual applies to the following instrument
versions:
•Hardware from 1.0.0
•Software from 1.0.0
•OnlyforinstrumentversionswithoutSILqualication
This electronics version can be determined via the product code on
the type label as well as on the electronics.
•Standard electronics: Type FX80HK.-
The scope of delivery encompasses:
•Sensor
•Documentation
– this operating instructions manual
– Testcerticatemeasuringaccuracy(optional)
– Operating instructions manual "Display and adjustment mod-
ule" (optional)
– Supplementary instructions "GSM/GPRSradiomodule"
(optional)
– Supplementary instructions manual "Heating for display and
adjustment module" (optional)
– Supplementary instructions manual "Plug connector for con-
tinuously measuring sensors" (optional)
– Ex-specic"Safety instructions" (with Ex versions)
– ifnecessary,furthercerticates
Electronics design
Scope of this operating
instructions manual
Versions
Scope of delivery

9
3 Product description
VEGAFLEX 81 • Modbus and Levelmaster protocol
42283-EN-140430
3.2 Principle of operation
The VEGAFLEX 81 is a level sensor with coax probe for continuous
level or interface measurement, suitable for applications in liquids.
High frequency microwave pulses are guided along a steel cable or
a rod. Upon reaching the product surface, the microwave pulses are
reected.Therunningtimeisevaluatedbytheinstrumentandoutput-
ted as level.
d
h
1
Fig. 3: Level measurement
1 Sensorreferenceplane(sealsurfaceoftheprocesstting)
d Distancetotheinterface(HARTvalue1)
h Height - Level
Probe end tracking
To increase sensitivity, the probe is equipped with probe end tracking.
In products with a low dielectric constant, this function is very helpful.
This is the case, for example, in plastic granules, packing chips or in
vesselswithuidizedproducts.
Between a dielectric constant of 1.5 and 3, the function switches on, if
required. As soon as the level echo can no longer be detected, probe
end tracking is automatically activated. The measurement is contin-
ued with the last calculated dielectric constant.
The accuracy thus depends on the stability of the dielectric constant.
If you measure a medium with a dielectric constant below 1.5, probe
end tracking is always active. In this case, you have to enter the
dielectric constant of the medium. A stable dielectric constant is very
important here.
High frequency microwave impulses are guided along a steel cable or
rod. Upon reaching the product surface, a part of the microwave im-
pulsesisreected.Theotherpartpassesthroughtheupperproduct
andisreectedbytheinterface.Therunningtimestothetwoproduct
layers are processed by the instrument.
Application area
Functional principle -
level measurement
Functional principle - in-
terface measurement

10
3 Product description
VEGAFLEX 81 • Modbus and Levelmaster protocol
42283-EN-140430
TS
d1
h1
h2
d2
1
L2
L1
L3
Fig. 4: Interface measurement
1 Sensorreferenceplane(sealsurfaceoftheprocesstting)
d1 Distancetotheinterface(HARTvalue1)
d2 Distancetothelevel(HARTvalue3)
TS Thicknessoftheuppermedium(d1-d2)
h1 Height - Interface
h2 Height - Level
L1 Lower medium
L2 Upper medium
L3 Gasphase
Upper medium (L2)
•The upper medium must not be conductive
•The dielectric constant of the upper medium or the actual distance
to the interface must be known (input required). Min. dielectric con-
stant:1.6.Yo u canndalistofdielectricconstantsonourhome
page: www.vega.com.
•The composition of the upper medium must be stable, no varying
products or mixtures
•Theuppermediummustbehomogeneous,nostratications
within the medium
•Min. thickness of the upper medium 50 mm (1.97 in)
•Clear separation from the lower medium, emulsion phase or detri-
tus layer max. 50 mm (1.97 in)
•If possible, no foam on the surface
Lower medium (L1)
•The dielectric constant must be 10 higher than the dielectric
constant of the upper medium, preferably electrically conductive.
Example: upper medium dielectric constant 2, lower medium at
least dielectric constant 12.
Gas phase (L3)
•Air or gas mixture
•Gas phase - dependent on the application, gas pahse does not
always exist (d2 = 0)
Prerequisites for inter-
face measurement

11
3 Product description
VEGAFLEX 81 • Modbus and Levelmaster protocol
42283-EN-140430
The instrument is always preset to the application "Level measure-
ment".
For the interface measurement, you can select the requested output
signal with the setup.
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.
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 or the external display and adjustment unit 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.
Output signal
Packaging
Transport
Transport inspection
Storage
Storage and transport
temperature
PLICSCOM
VEGACONNECT

12
3 Product description
VEGAFLEX 81 • Modbus and Levelmaster protocol
42283-EN-140430
Youcanndfurtherinformationintheoperatinginstructions"Interface
adapterVEGACONNECT" (Document-ID 32628).
The VEGADIS 81 is an external display and adjustment unit for VEGA
plics® sensors.
For sensors with double chamber housing the interface adapter "DIS-
ADAPT" is also required for VEGADIS 81.
Youcanndfurtherinformationintheoperatinginstructions"VE-
GADIS81" (Document-ID 43814).
The adapter "DIS-ADAPT" is an accessory part for sensors with
double chamber housings. It enables the connection of VEGADIS 81
to the sensor housing via an M12 x1 plug.
Youcanndfurtherinformationinthesupplementaryinstructions
"AdapterDISADAPT" (Document-ID 45250).
The PLICSMOBILE T61 is an external GSM/GPRS radio unit for
transmission of measured values and for remote parameter adjust-
ment of plics® sensors. The adjustment is carried out via PACTware/
DTM by using the integrated USB connection.
Youcanndfurtherinformationinthesupplementaryinstructions
"PLICSMOBILET61" (Document-ID 37700).
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, ANSI 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" (Document-ID
31088).
The electronics module VEGAFLEX series 80 is a replacement part
forTDRsensorsofVEGAFLEXseries80.Thereisadierentversion
available for each type of signal output.
Youcanndfurtherinformationintheoperatinginstructionsmanual
"ElectronicsmoduleVEGAFLEXseries80".
The electronics module Modbus is a replacement part for TDR sen-
sors of VEGAFLEX series 80.
Youcanndfurtherinformationintheoperatinginstructionsmanual
"ElectronicsmoduleModbusVEGAFLEXseries80".
The display and adjustment module can be optionally replaced by a
display and adjustment module with heating function.
You can use this display and adjustment module in an ambient tem-
perature range of -40 … +70 °C.
VEGADIS 81
DIS-ADAPT
PLICSMOBILE T61
Protective cap
Flanges
Electronics module
Electronics module,
Modbus
Display and adjustment
module with heating

13
3 Product description
VEGAFLEX 81 • Modbus and Levelmaster protocol
42283-EN-140430
Youcanndfurtherinformationintheoperatinginstructions"Display
and adjustment module with heating" (Document-ID 31708).

14
4 Mounting
VEGAFLEX 81 • Modbus and Levelmaster protocol
42283-EN-140430
4 Mounting
4.1 General instructions
Oninstrumentswithprocessttingthread,thehexagonmustbetight-
enedwithasuitablescrewdriver.Wrenchsizeseechapter"Dimen-
sions".
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 penetration through the fol-
lowing measures:
•Use the recommended cable (see chapter "Connectingtopower
supply")
•Tighten the cable gland
•Turn the housing in such a way that the cable gland points down-
ward
•Loop the connection cable downward in front of the cable gland
This applies particularly to:
•Outdoor mounting
•Installations in areas where high humidity is expected (e.g. through
cleaning processes)
•Installations on cooled or heated vessels
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
openings for the cable glands are therefore covered with red protec-
tive caps as transport protection.
Prior to setup you have to replace these protective caps with ap-
proved cable glands or close the openings with suitable blind plugs.
The suitable cable glands and blind plugs come with the instrument.
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thespecicationsoftheprocessconditionsinchapter
"Technicaldata" as well as on the type label.
Screwing in
Protection against mois-
ture
Protective caps
Suitability for the process
conditions

15
4 Mounting
VEGAFLEX 81 • Modbus and Levelmaster protocol
42283-EN-140430
4.2 Mounting instructions
During operation, the probe must not touch any installations or the
vessel wall. If necessary, fasten the probe end.
In vessels with conical bottom it can be advantageous to mount the
sensor in the center of the vessel, as measurement is then possible
nearly down to the lowest point of the bottom. Keep in mind that
measurement all the way down to the tip of the probe may not be pos-
sible. The exact value of the min. distance (lower dead band) is stated
in chapter "Technicaldata".
Fig. 5: Vessel with conical bottom
Before beginning the welding work, remove the electronics module
from the sensor. By doing this, you avoid damage to the electronics
through inductive coupling.
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.6:Mountingofthesensorwithinowingmedium
Installation position
Welding work
Inowingmedium

16
4 Mounting
VEGAFLEX 81 • Modbus and Levelmaster protocol
42283-EN-140430
The reference plane for the measuring range of the sensors is the
sealingsurfaceofthethreadorange.
Keep in mind that a min. distance must be maintained below the refer-
ence plane and possibly also at the end of the probe - measurement
in these areas is not possible (dead band). These dead bands are
listed in chapter "Technicaldata". Keep in mind for the adjustment that
the default setting for the measuring range refers to water.
Theprocessttingmustbesealedifthereisgaugeorlowpressurein
the vessel. Before use, check if the seal material is resistant against
the measured product and the process temperature.
Themax.permissiblepressureisspeciedinchapter"Technical
data" or on the type label of the sensor.
Vapours, superimposed gases, high pressures and temperature dif-
ferences can change the spreading speed of radar impulses.
There are two possibilities to correct these deviations.
Corrective value in the process control system
Inthetechnicaldataunder"Inuenceofsuperimposedgasandpres-
sureonaccuracy"youcanndatablewithdeviationvaluesinsome
typical gases or in steam.
In the control system (DCS) you can correct the measurement results
of the VEGAFLEX 81 with these values.
The prerequisite is constant temperature and pressure in the vessel.
Automatic correction via the reference distance
The VEGAFLEX 81 can be equipped optionally with a running time
correction via reference distance. The probe can carry out an auto-
matic running time correction with it.
Thereferencepointmusthencenotbeoverlled.Theupperdead
band is hence 450 mm (17.7 in).
Measuring range
Pressure
Steam boiler applications

17
4 Mounting
VEGAFLEX 81 • Modbus and Levelmaster protocol
42283-EN-140430
2
6
3
4
5
1
Fig.7:Measuringranges-VEGAFLEX81withsteamcompensation
1 Reference plane
2 Probe length L
3 Measuring range
4 Upper dead zone with steam compensation = 450 mm (17.7 in)
5 Lower dead band
6 Reference measurement distance to steam compensation

18
5 Connecting to power supply
VEGAFLEX 81 • Modbus and Levelmaster protocol
42283-EN-140430
5 Connecting to power supply
5.1 Preparing the connection
Always keep in mind the following safety instructions:
•Connect only in the complete absence of line voltage
•If overvoltage surges are expected, overvoltage arresters should
be installed
The instrument requires an operating voltage of 8 … 30 V DC. Operat-
ing voltage and digital bus signal are carried on separate two-wire
connection cables.
The instrument is connected with standard two-wire, twisted cable
suitable for RS 485. If electromagnetic interference is expected which
is above the test values of EN 61326 for industrial areas, screened
cable should be used.
For instruments with housing and cable gland, use cable with round
cross-section.To ensurethesealeectofthecablegland(IPprotec-
tion rating), you have to check for which cable outer diameter the
cable gland is suitable.
Useacableglandttingthecablediameter.
Make sure that the entire installation is carried out according to the
Fieldbusspecication.Inparticular,makesurethatthebusistermi-
nated with suitable terminating resistors.
With plastic housing, the NPT cable gland or the Conduit steel tube
must be screwed without grease into the threaded insert.
Max. torque for all housings see chapter "Technicaldata".
In systems with potential equalisation, connect the cable screen
directly to ground potential at the power supply unit, in the connection
box and at the sensor. The screen in the sensor must be connected
directly to the internal ground terminal. The ground terminal outside
on the housing must be connected to the potential equalisation (low
impedance).
In systems without potential equalisation, connect the cable screen
directly to ground potential at the power supply unit and at the sensor.
In the connection box or T-distributor, the screen of the short stub to
the sensor must not be connected to ground potential or to another
cable screen. The cable screens to the power supply unit and to the
next distributor must be connected to each other and also connected
to ground potential via a ceramic capacitor (e.g. 1 nF, 1500 V). The
low frequency potential equalisation currents are thus suppressed,
buttheprotectiveeectagainsthighfrequencyinterferencesignals
remains.
5.2 Connecting
The voltage supply and signal output are connected via the spring-
loaded terminals in the housing.
Safety instructions
Voltage supply
Connection cable
Cable gland ½ NPT
Cable screening and
grounding
Connection technology

19
5 Connecting to power supply
VEGAFLEX 81 • Modbus and Levelmaster protocol
42283-EN-140430
Connection to the display and adjustment module or to the interface
adapter is carried out via contact pins in the housing.
Information:
The terminal block is pluggable and can be removed from the
electronics. To do this, lift the terminal block with a small screwdriver
and pull it out. When reinserting the terminal block, you should hear it
snap in.
Proceed as follows:
1. Unscrew the housing cover
2. If a display and adjustment module is installed, remove it by turn-
ing it slightly to the left.
3. Loosen compression nut of the cable entry gland
4. Remove approx. 10 cm (4 in) of the cable mantle, strip approx.
1 cm (0.4 in) of insulation from the ends of the individual wires
5. Insert the cable into the sensor through the cable entry
Fig.8:Connectionsteps5and6-Singlechamberhousing
Connection procedure

20
5 Connecting to power supply
VEGAFLEX 81 • Modbus and Levelmaster protocol
42283-EN-140430
Fig.9:Connectionsteps5and6-Doublechamberhousing
6. Insert the wire ends into the terminals according to the wiring plan
Information:
Solidcoresaswellasexiblecoreswithwireendsleevesareinsert-
eddirectlyintotheterminalopenings.Incaseofexiblecoreswithout
end sleeves, press the terminal from above with a small screwdriver,
the terminal opening is then free. When the screwdriver is released,
the terminal closes again.
Youcanndfurtherinformationonthemax.wirecross-sectionunder
"Technicaldata/Electromechanicaldata"
7. Check the hold of the wires in the terminals by lightly pulling on
them
8. Connect the screen to the internal ground terminal, connect the
outer ground terminal to potential equalisation
9. Tighten the compression nut of the cable entry gland. The seal
ring must completely encircle the cable
10. Reinsert the display and adjustment module, if one was installed
11. Screw the housing cover back on
Theelectricalconnectionisnished.