Siemens SITRANS LG270 User manual

Operating Instructions • 03/2014
Guided Wave Radar
SITRANS LG270
Modbus and Levelmaster protocol
Rod and cable probe

2PBD-51041066SITRANS LG270 - Operating Instructions
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PBD-51041066 SITRANS LG270 - Operating Instructions
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Contents
1About this document
1.1 Function ........................................................................................................................... 5
1.2 Target group ..................................................................................................................... 5
1.3 Symbols used................................................................................................................... 5
2For your safety
2.1 Authorised personnel ....................................................................................................... 6
2.2 Appropriate use................................................................................................................ 6
2.3 Warning about incorrect use............................................................................................. 6
2.4 General safety instructions............................................................................................... 6
2.5 CE conformity................................................................................................................... 6
2.6 NAMUR recommendations .............................................................................................. 7
2.7 Environmental instructions ............................................................................................... 7
3Product description
3.1 Conguration.................................................................................................................... 8
3.2 Principle of operation........................................................................................................ 9
3.3 Packaging, transport and storage................................................................................... 12
3.4 Accessories and replacement parts ............................................................................... 12
4Mounting
4.1 General instructions ....................................................................................................... 14
4.2 Mounting instructions ..................................................................................................... 15
5 Connecting to power supply and bus system
5.1 Preparing the connection ............................................................................................... 23
5.2 Connecting..................................................................................................................... 24
5.3 Wiring plan ..................................................................................................................... 26
5.4 Double chamber housing with DIS-ADAPT .................................................................... 27
5.5 Supplementary electronics............................................................................................. 28
5.6 Switch-on phase............................................................................................................. 28
6 Set up the sensor with the display and adjustment module
6.1 Adjustment volume......................................................................................................... 29
6.2 Insert display and adjustment module............................................................................ 29
6.3 Adjustment system......................................................................................................... 30
6.4 Parameter adjustment - Quick setup .............................................................................. 31
6.5 Parameter adjustment - Extended adjustment................................................................ 33
6.6 Saving the parameter adjustment data........................................................................... 52
7 Setting up sensor and Modbus interface with PACTware
7.1 Connect the PC.............................................................................................................. 54
7.2 Parameter adjustment with PACTware............................................................................ 55
7.3 Set up with the quick setup............................................................................................. 56
7.4 Saving the parameter adjustment data........................................................................... 61
8 Diagnostics and service
8.1 Maintenance .................................................................................................................. 62
8.2 Diagnosis memory ......................................................................................................... 62
8.3 Status messages............................................................................................................ 63
8.4 Rectify faults................................................................................................................... 67
8.5 Exchanging the electronics module................................................................................ 69

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8.6 Exchange or shorten cable/rod ...................................................................................... 70
8.7 Software update ............................................................................................................. 72
8.8 How to proceed if a repair is needed.............................................................................. 72
9 Dismounting
9.1 Dismounting steps.......................................................................................................... 73
9.2 Disposal ......................................................................................................................... 73
10 Supplement
10.1 Technical data ................................................................................................................ 74
10.2 Basics Modbus............................................................................................................... 84
10.3 Modbus register ............................................................................................................. 86
10.4 Modbus RTU commands ............................................................................................... 88
10.5 Levelmaster commands ................................................................................................. 91
10.6 CongurationoftypicalModbushosts ........................................................................... 95
10.7 Dimensions .................................................................................................................. 100
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: 2014-03-17

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PBD-51041066 SITRANS LG270 - Operating Instructions
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1About 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.
1Sequence 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.

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2For 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
SITRANS LG270 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.

7PBD-51041066 SITRANS LG270 - Operating Instructions
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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"

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3Product description
3.1 Conguration
Thetypelabelcontainsthemostimportantdataforidenticationand
use of the instrument:
2
1
5
3
6
4
7
8
11
12
13
10
9
1
Fig. 1: Layout of the type label (example)
1 Instrument type
2 Product code
3 Process and ambient temperature, process pressure
4 Process pressure
5 Signal output electronics
6 Voltage supply
7 Protection rating
8 Order number
9 Identicationcode
10 Serial number of the instrument
11 Symbol of the device protection class
12 Reminder to observe the instrument documentation
13 ID numbers, instrument documentation
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
Type label
Electronics design

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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 manual "Plug connector for con-
tinuously measuring sensors"(optional)
– Ex-specic"Safety instructions"(withExversions)
– ifnecessary,furthercerticates
3.2 Principle of operation
The SITRANS LG270 is a level sensor with cable or rod probe for
continuous level or interface measurement, particularly suitable for
applicationsinhightemperaturesupto+450°C(842°F).
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.
Scope of this operating
instructions manual
Versions
Scope of delivery
Application area
Functional principle -
level measurement

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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.
Functional principle - in-
terface measurement

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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.siemens.com/sitranslg.
•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

12 PBD-51041066SITRANS LG270 - Operating Instructions
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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 LG Local Display Interface is
used for measured value indication, adjustment and diagnosis. It can
be inserted into the sensor and removed at any time.
Youcanndadditionalinformationintheoperatinginstructions
manual "LG Local Display Interface"(Document-ID43838).
The LG Remote Interface is an external display and adjustment unit
for sensors with single chamber housing and Ex-d double chamber
housing.
It is suitable for measured value indication and adjustment of sensors
and is connected to the sensor with a four-wire standard cable up to
50m(164ft)long.
Output signal
Packaging
Transport
Transport inspection
Storage
Storage and transport
temperature
Display and adjustment
module
External display and
adjustment unit

13PBD-51041066 SITRANS LG270 - Operating Instructions
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Youcanndadditionalinformationintheoperatinginstructions
manual "LG Remote Interface".
The adapter "DIS-ADAPT" is an accessory part for sensors with dou-
ble chamber housings. It enables the connection of the exterbal dis-
play and adjustment unit to the sensor housing via an M12 x 1 plug.
Youcanndfurtherinformationinthesupplementaryinstructions
"Adapter DISADAPT".
The electronics module SITRANS series LG is a replacement part for
TDRsensorsofSITRANSseriesLG.Thereisadierentversionavail-
able for each type of signal output.
Youcanndfurtherinformationintheoperatinginstructionsmanual
"Electronics module SITRANS series LG".
The electronics module Modbus is a replacement part for TDR sen-
sors of SITRANS series LG.
Youcanndfurtherinformationintheoperatinginstructionsmanual
"Electronics module Modbus SITRANS series LG".
If you are using an instrument with rod version, you can extend the
rod probe individually with curved segments and rod extensions of
dierentlengths.
Allextensionsusedmustnotexceedatotallengthof6m(19.7ft).
The extensions are available in the following lengths:
Rod: ø 16 mm (0.63 in)
•Basicsegments:20…5900mm(0.79…232in)
•Rodsegments:20…5900mm(0.79…232in)
•Curvedsegments:100x100mm(3.94…3.94in)
Youcanndfurtherinformationintheoperatinginstructionsmanual
"Rod extension SITRANS series LG".
If you mount the SITRANS LG270 in a bypass tube or standpipe, you
have to avoid contact to the bypass tube by using a spacer at the
probe end.
Youcanndadditionalinformationintheoperatinginstructions
manual "Centering".
DIS-ADAPT
Electronics module
Electronics module,
Modbus
Rod extension
Spacer

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4Mounting
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

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4.2 Mounting instructions
Mount SITRANS LG270 in such a way that the distance to vessel
installationsortothevesselwallisatleast300mm(12in).Innon-
metallic vessels, the distance to the vessel wall should be at least
500mm(19.7in).
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
Plastic vessel/Glass vessel
The guided microwave principle requires a metallic surface on the
processtting.Therefore,inplasticvessels,etc.,useaninstru-
mentversionwithange(fromDN50)orplaceametalsheet
(ø>200mm/8in)beneaththeprocessttingwhenscrewingitin.
Makesurethattheplatehasdirectcontactwiththeprocesstting.
When installing rod or cable probes in vessels without metal walls,
e.g.inplasticvessels,themeasuredvaluecanbeinuencedby
strongelectromagneticelds(emittedinterferenceaccordingto
EN61326:classA).Inthiscase,useaprobewithcoaxialversion.
Installation position
Type of vessel

16 PBD-51041066SITRANS LG270 - Operating Instructions
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1 2
Fig. 6: Installation in non-metallic vessel
1 Flange
2 Metal sheet
Ifpossible,avoidsockets.Mountthesensorushwiththevesseltop.
If this is not possible, use short sockets with small diameter.
Higher sockets or sockets with a bigger diameter can generally be
used.Theycan,however,increasetheupperblockingdistance(dead
band).Checkifthisisrelevantforyourmeasurement.
In such cases, always carry out a false signal suppression after instal-
lation.Yo u canndfurtherinformationunder"Setup procedure".
h
d
dh
DN40...DN150
>DN150... DN200 150
100
_
<
_
<
Fig. 7: Mounting socket
Whenweldingthesocket,makesurethatthesocketisushwiththe
vessel top.
Socket

17PBD-51041066 SITRANS LG270 - Operating Instructions
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1 2
Fig.8:Socketmustbeinstalledush
1 Unfavourable installation
2 Socketush-optimuminstallation
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.9:Mountingofthesensorwithinowingmedium
The reference plane for the measuring range of the sensors is the
sealingsurfaceofthethreadorange.
Welding work
Inowingmedium
Measuring range

18 PBD-51041066SITRANS LG270 - Operating Instructions
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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).Thelengthofthecable
can be used all the way to the end only when measuring conductive
products.Theseblockingdistancesfordierentmediums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.
Standpipes or bypass tubes are normally metal tubes with a diameter
of30…200mm(1.18…7.87in).Inmeasurementtechnology,such
a tube corresponds to a coax probe. It does not matter if the stand-
pipe is perforated or slotted for better mixing. Lateral inlets in bypass
tubesalsodonotinuencethemeasurement.
Measuring probes can be mounted in bypass tubes up to DN 200.
For bypass tubes, select the probe length such that the blocking
distance(deadband)oftheprobeisaboveorbelowthelaterallling
openings.You can thus measure the complete range of the medium in
the bypass tube. When designing the bypass tube, keep the blocking
distance of the probe in mind and select the length above the upper
lateralllingopeningaccordingly.
Microwaves can penetrate many plastics. For process technical rea-
sons, plastic standpipes are problematic. If durability is no problem,
then we recommend the use of metal standpipes.
When the SITRANS LG270 is used in standpipes or bypass tubes,
contact with the tube wall must be avoided. We recommend for this
purpose a cable probe with centering weight.
With rod probes, a spacer is generally not required. However, if there
is a risk of the rod probe being pressed against the tube wall by in-
owingmedium,youshouldmountaspacerattheprobeendtoavoid
contact with the tube wall. In the case of cable probes, the cable can
be strained.
Keep in mind that buildup can form on the spacers. Strong buildup
caninuencethemeasurement.
Pressure
Standpipes or bypass
tubes

19PBD-51041066 SITRANS LG270 - Operating Instructions
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12
Fig. 10: Position of the spacer or centering weight
1 Rod probe with spacer (steel)
2 Cable probe with centering weight
Note:
Measurement in a standpipe is not recommended for extremely
adhesive products.
Instructions for the measurement:
•The 100 % point should not be above the upper tube connection
to the vessel
•The 0 % point should not be below the lower tube connection to
the vessel
•A false signal suppression with installed sensor is generally rec-
ommended to achieve maximum possible accuracy.
Instruments for a temperature range up to 280 °C or up to 450 °C
haveadistancepiecebetweenprocessttingandelectronicshous-
ing. Ths distance piece is used for thermal decoupling of the electron-
ics against high process temperatures.
Information:
Thedistancepiecemustonlybeincorporateduptomax.50mm(2in)
in the vessel isolation. Only then, a reliable temperature decoupling is
guaranteed.
Mounting in the vessel
insulation

20 PBD-51041066SITRANS LG270 - Operating Instructions
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1
2
Fig. 11: Mounting the instrument on insulated vessels.
1 Temperature insulation
2 Ambient temperature on the housing
If there is a risk of the cable probe touching the vessel wall during
operation due to product movements or agitators, etc., the measuring
probeshouldbesecurelyxed.
Thereisaninsidethread(M8)inthegravityweight,e.g.foraneye-
bolt(optional).
Make sure that the probe cable is not completely taut. Avoid tensile
loads on the cable.
Avoidundenedvesselconnections,i.e.theconnectionmustbe
eithergroundedreliablyorisolatedreliably.Anyundenedchangeof
this requirement can lead to measurement errors.
If there is a danger of the rod probe touching the vessel wall, then the
probe must be fastened at the bottom end.
Keep in mind that below the fastening, a measurement is not possible.
Fasten