IFM LW2720 User manual

Operating instructions
Electronic level sensor
LW2720
11372800 / 0002 / 2021
GB

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Contents
1 Preliminary note.............................................................. 4
1.1 Symbols used........................................................... 4
1.2 Warnings used.......................................................... 4
2 Safety instructions............................................................ 5
3 Intended use ................................................................ 6
3.1 Application area......................................................... 6
3.1.1 Application examples.................................................. 6
3.2 Restriction of the application area ........................................... 7
4 Items supplied ............................................................... 8
5 Function.................................................................... 9
5.1 Measuring principle ...................................................... 9
5.1.1 Reflectivity, effect of dielectric constant. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
5.1.2 Foam and turbulence.................................................. 10
5.1.3 Influence of vessel characteristics and installation . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
5.2 IO-Link................................................................ 10
5.3 Outputs ............................................................... 10
5.3.1 Analogue output ..................................................... 10
5.3.2 Switching function.................................................... 11
5.3.3 Defined state in the event of a fault (alert mode). . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
5.3.4 Simulation function ................................................... 13
5.3.5 Damping function .................................................... 13
5.4 Output response in different operating states. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
6 Mounting ................................................................... 14
6.1 Mounting position........................................................ 14
6.2 Inclination.............................................................. 15
6.3 Non-metallic tanks....................................................... 15
6.4 Beam angle and beam width............................................... 15
6.5 Nozzle requirements ..................................................... 16
6.6 Notes for hygienic applications.............................................. 16
6.6.1 Notes on the use according to EHEDG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
6.6.2 Notes on the use according to 3-A® . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6.7 Mounting in a threaded connection .......................................... 17
6.8 Mounting preparations.................................................... 17
6.8.1 Remove the protective cap............................................. 17
6.8.2 Place the O-ring, grease the thread . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
6.8.3 Premount the adapter for pipe fittings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
6.8.4 Install the welding aid ................................................. 19
6.9 Mount the unit in the tank.................................................. 21
6.9.1 Mount the unit with Tri Clamp adapter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
6.9.2 Mount the unit with pipe fitting........................................... 22
6.9.3 Mount the unit with VARIVENT® adapter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
6.9.4 Install the weld-in adapter on the unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
6.9.5 Mount the unit with G1 connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
7 Electrical connection .......................................................... 25
8 Parameter setting............................................................. 26
8.1 Parameter setting via PC and IO-Link master . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
8.2 Parameter setting during operation .......................................... 26
8.3 Adjustable parameters.................................................... 27
8.4 System commands....................................................... 31
8.5 Example parameter setting ................................................ 31
9 Operation................................................................... 33
9.1 Function check.......................................................... 33
9.1.1 Detection quality check................................................ 33
9.2 Diagnostic messages, cause, troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
10 Troubleshooting.............................................................. 35

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10.1 Troubleshooting incorrect level readings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
10.1.1 Level too high / too low................................................ 35
10.1.2 Measured value is stuck............................................... 35
10.1.3 Measured value drops when level close to antenna . . . . . . . . . . . . . . . . . . . . . . . . . . 36
10.1.4 Measured value fluctuates.............................................. 37
10.1.5 Measured value is occasionally unstable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
10.1.6 Lagging of measured value during rapid level changes . . . . . . . . . . . . . . . . . . . . . . . 38
10.1.7 Measured value correct at 0% (4mA) but incorrect at 100% (20mA) . . . . . . . . . . . . 39
10.1.8 Incorrect measured value when level is above 50% . . . . . . . . . . . . . . . . . . . . . . . . . . 39
10.1.9 Measured value drops to zero close to tank bottom . . . . . . . . . . . . . . . . . . . . . . . . . . 39
10.1.10 Level measurement is lost in an empty tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
10.1.11 Alert mode when level close to tank bottom . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
11 Maintenance, repair and disposal ................................................ 42
12 Factory setting............................................................... 43
13 Appendix ................................................................... 44
13.1 Approvals and certificates ................................................. 44
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1 Preliminary note
You will find instructions, technical data, approvals and further information using the QR code on the
unit / packaging or at www.ifm.com.
1.1 Symbols used
Requirement
Instructions
Reaction, result
[...] Designation of keys, buttons or indications
Cross-reference
Important note
Non-compliance may result in malfunction or interference.
Information
Supplementary note
1.2 Warnings used
CAUTION
Warning of personal injury
wSlight reversible injuries may result.

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2 Safety instructions
• The unit described is a subcomponent for integration into a system.
– The system architect is responsible for the safety of the system.
– The system architect undertakes to perform a risk assessment and to create documentation in
accordance with legal and normative requirements to be provided to the operator and user of
the system. This documentation must contain all necessary information and safety instructions
for the operator, the user and, if applicable, for any service personnel authorised by the
architect of the system.
• Read this document before setting up the product and keep it during the entire service life.
• The product must be suitable for the corresponding applications and environmental conditions
without any restrictions.
• Only use the product for its intended purpose (Ò Intended use).
• Only use the product for permissible media (Ò Technical data).
• If the operating instructions or the technical data are not adhered to, personal injury and/or damage
to property may occur.
• The manufacturer assumes no liability or warranty for any consequences caused by tampering with
the product or incorrect use by the operator.
• Installation, electrical connection, set-up, operation and maintenance of the product must be
carried out by qualified personnel authorised by the machine operator.
• Protect units and cables against damage.
• The standards the unit complies with include TLPR and CISPR 11. Further standards and
specifications: Ò data sheet.
Radiated microwave energy:
The microwave energy radiated by the unit is much below that of mobile phones.
Maximum radiated energy: 2 mW.
According to the current state of science the operation of the unit can be classified to be
harmless to human health.
CAUTION
With high process temperatures, parts of the unit may heat up.
wRisk of burns
uDo not touch the unit.
uProtect the housing against contact with flammable substances and unintentional
contact.
uAllow the unit and process adapter to cool down before maintenance.
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3 Intended use
The unit continuously monitors the level of liquids in tanks without contact. Bulk materials are detected
depending on their properties (conical heaps, grain size, dielectric constant, etc.).
3.1 Application area
Non-contacting radar technology is ideally suited for food and beverage applications as it is
maintenance-free, has a top-down installation that reduces the risk of leakages, and is unaffected by
process conditions such as density, viscosity, temperature, pressure and pH.
The unit combines the innovative 80 GHz technology with the FMCW method and smart algorithms to
maximise measurement accuracy and reliability, even in small tanks and challenging fast-filling/ fast-
emptying vessels.
3.1.1 Application examples
Storage tank:
Provides insight into the tank and ensures production runs smoothly
without interruption.
Mixing tank:
Ensures correct filling and storage levels in tanks with agitators.
Batch filling:
Optimises the batch filling process.

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CIP process:
The unit withstands standard CIP routines and SIP routines up to
140°C.
Optimisation of cleaning agent storage.
3.2 Restriction of the application area
• The unit is not suitable for some bulk materials (e.g. coffee beans) due to their often very low
dielectric constant.
• Detection of bulk materials with a higher dielectric constant (e.g. grist due to its higher moisture
content) may be possible. See: Reflectivity, effect of dielectric constant (Ò/9)
uCheck the function by performing an application test.
• The unit is a TLPR device. TLPR (Tank Level Probing Radar) equipment are devices for level
measurement in a closed space only (i.e. metallic, reinforced concrete or fibreglass tanks, or
similar enclosure structures made of comparable attenuating material).
uInstallation must be carried out in accordance with the requirements of the following
standard: ETSI EN 302 372 (TLPR), Annex E
• Use preferably in metal tanks. When used in electrically non-conductive tanks (e.g. fibreglass
tanks):
– there may be deterioration caused by electromagnetic interference from other devices (noise
immunity according to EN 61326-1). Corrective measures: Non-metallic tanks (Ò/15)
– or if the mounting position is unfavourable, nearby objects outside the tank may cause
disturbing echoes.
Incorrect measurements may be caused by the following media:
• heavily foaming or turbulent surfaces.
• media which are very inhomogeneous, separate from each other thus forming separation layers
(e.g. oil layer on water).
uCheck the function by performing an application test.
uInstallation in a steady area.
wIn case of permanent signal loss, the unit generates an error message and switches the outputs to
a defined state.
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4 Items supplied
• LW2720 level sensor.
• Product information with safety instructions and reference to the complete operating instructions at
www.ifm.com.
In addition, the following is necessary for installation and operation:
• Mounting material (Ò Accessories)
Only use accessories from ifm electronic gmbh! The optimum function is not ensured when
using components from other manufacturers.
Available accessories: www.ifm.com.

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5 Function
5.1 Measuring principle
The measuring principle of the unit is Frequency Modulated Continuous Wave (FMCW). The unit
continuously emits electromagnetic waves in the GHz range with a constantly varying frequency
towards the medium surface. Since the transmitter continuously changes the frequency of the
transmitted signal, there will be a difference in frequency between the transmitted and the reflected
signals (Ò Fig. Measuring principle). The frequency of the reflected signal is subtracted from the
frequency of the signal transmitted at that moment, resulting in a low frequency signal which is
proportional to the distance to the medium surface. This signal is further processed to obtain fast,
reliable, and highly accurate level measurements.
d
fin
fmax
fmin
fout
fin fout
t
f
A
C
D
B
Fig.1: Measuring principle
Δf ~ d = distance
A: frequency (GHz)
B: time (s)
C: transmitted signal
D: reflected signal
Due to the 80GHz technology used, the unit generates a very focused signal beam (beam angle
approx. 10°). This extends the range of possible applications and enables installation even in small
tanks and confined spaces (e.g. in tanks with agitators, heating coils, etc.).
5.1.1 Reflectivity, effect of dielectric constant
The reflectivity of the medium has a substantial effect on the reflected signal (echo amplitude). The
reflectivity is directly dependent on the dielectric constant of the medium. A high dielectric constant
provides better reflectivity, thus improving the performance of the level measurement. This also
indirectly affects the maximum achievable level measuring range. Minimum dielectric constant: Ò
Data sheet
Dielectric constant (also: relative permittivity) of some media
Air (reference quantity) 1
Water ≈ 80
Salt water ≈ 32
Water, demineralised ≈ 30
Beer brew ≈ 25
Vinegar ≈ 24
Maize starch ≈ 18
Coarse soya flour, 19% moisture ≈ 18
Coarse soya flour, dry (application test recommended) ≈ 3
Vegetable oil (application test recommended) ≈ 2…4
Grist (application test recommended) ≈ 2…3
Malt (application test recommended) ≈ 2…3
Skimmed milk powder (application test recommended) ≈ 2
Palm oil (not detected reliably) ≈ 1.8
Coffee beans (not detected reliably) ≈ 1.5
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5.1.2 Foam and turbulence
Foaming liquids or turbulence may cause weak and varying echo amplitudes. Surface turbulence is
not normally a problem unless it is excessive.
Measurement in foamy applications depends largely on the foam properties. If the foam is light and
airy, the actual level is measured. For heavy and dense foam, the unit may measure the level of the
foam’s upper surface.
5.1.3 Influence of vessel characteristics and installation
The unit should be mounted so that objects such as heating coils, ladders and agitators are not in the
radar signal path. These objects may cause false echoes which can affect the measurement and lead
to measurement errors. However, the unit has built-in functions designed to reduce the influence from
disturbing objects where such objects cannot be totally avoided. Vertical and inclined structures cause
minimal effect since the radar signal is scattered rather than directed back to the antenna.
5.2 IO-Link
The unit has an IO-Link communication interface which requires an IO-Link capable module (IO-Link
master).
The IO-Link interface enables direct access to the process and diagnostic data and provides the
possibility to set the parameters of the unit during operation.
In addition, communication is possible via a point-to-point connection with a USB IO-Link master.
The IODDs necessary for the configuration of the unit, detailed information about process data
structure, diagnostic information, parameter addresses and the necessary information about the
required IO-Link hardware and software can be found at www.ifm.com.
5.3 Outputs
The unit generates output signals according to the parameter setting. Two outputs are available:
• OUT1: switching output / IO-Link
• OUT2: analogue output 4...20 mA or switching output (configurable)
5.3.1 Analogue output
The unit provides an analogue signal proportional to the level (according to NAMUR NE43, DIN IEC
60381-1) or a switching signal on output OUT2. The analogue output can be configured.
• Parameter [ou2] = [I] sets output OUT2 as analogue output.
• Parameter [ASP2] sets at which measured value 4mA are provided.
• Parameter [AEP2] sets at which measured value 20mA are provided.
• If [ASP2] is set lower than [AEP2], a rising curve results; if [ASP2] is set higher than [AEP2], a
dropping curve results (Ò Fig. Analogue output).
Minimum distance between [ASP2] and [AEP2] = 20 % of the active zone

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100%
(20mA)
0%
(4mA)
D
C
A
B
2
1
I [mA]
L
20
4
ASP2
(AEP2)
AEP2
(ASP2)
Fig.2: Analogue output
A: blind zone I: current
B: zone with reduced accuracy L: level
C: recommended measuring range 1: rising curve ([ASP2]<[AEP2])
D: zero point = reference point 2: dropping curve ([ASP2]>[AEP2])
Note the tolerances and accuracies during the evaluation of the analogue signal
(Ò Data sheet).
5.3.2 Switching function
Via switching output OUT1 (factory setting) or additionally via OUT2 (can be set) the unit signals that a
set limit level has been reached or that the level is below the limit. The following switching functions
can be selected:
• hysteresis function / normally open or normally closed (Ò Fig. Single-point mode and fig. Two-point
mode)
• window function / normally open or normally closed (Ò Fig. Window function)
The hysteresis function can be applied in single-point mode and in two-point mode. Functionally, both
modes are the same; only the setting method differs.
The explanations below refer to output OUT1.
Hysteresis function single-point mode:
u[SSC1 Config. Mode] must be set to [Single point].
uFirst the set point [SSC1 Param. SP1] is set, then the hysteresis [SSC1 Config. Hysteresis] with the
requested difference (Ò Fig. Single-point mode).
The normally open or normally closed function is set by [SSC1 Config. Logic]:
[no] = normally open / [nc] = normally closed.
Hysteresis function two-point mode:
u[SSC1 Config. Mode] must be set to [Two point].
u[SSC1 Param. SP1] sets the set point and [SSC1 Param. SP2] sets the reset point (Ò Fig. Two-
point mode).
u[SSC1 Param. SP1] must be greater than [SSC1 Param. SP2].
The normally open or normally closed function is set by [SSC1 Config. Logic]:
[no] = normally open / [nc] = normally closed.
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L
SP1 HY
no
nc
t
Fig.3: Single-point mode
L
SP1
SP2
no
nc
t
Fig.4: Two-point mode
L: level
t: time
HY: hysteresis
Window function:
u[SSC1 Config. Mode] must be set to [Window].
The width of the window can be set by means of the difference between [SSC1 Param. SP1] and
[SSC1 Param. SP2] (Ò Fig. Window function).
u[SSC1 Param. SP1] must be greater than [SSC1 Param. SP2].
The normally open or normally closed function is set by [SSC1 Config. Logic]: [no] = normally open /
[nc] = normally closed.
If desired, a hysteresis can be set at the window limits using [SSC1 Config. Hysteresis].
L
SP1
SP2
no
nc
t
W
Fig.5: Window function
L: level
t: time
W: window
The limit values [SSCx Param. SPx] are always absolute to the zero point = reference point (Fig.
Analogue output). The hystereses [SSCx Config. Hysteresis] are always relative to the limit values.
For the switching outputs, a switch-on and switch-off delay of max. 60s can be set (e.g. for especially
long pump cycles). The switch-on delay always refers to the limit value, the switch-off delay always
refers to the hysteresis.
5.3.3 Defined state in the event of a fault (alert mode)
For output OUT2, a state in the event of a fault can be defined.
If a fault is detected or if the signal quality is below a minimum value, the unit changes into the alert
mode and output OUT2 passes into a defined state according to NAMUR recommendation (NE43).
For this case, the response of the output can be set via the parameter [FOU2].
The unit can pass into the alert mode with delay. This can be useful if short-term errors occur or the
signal is reduced briefly (below the minimum value), e.g. due to turbulence or foam formation. The
delay time can be set (parameter [Alert mode delay time]). During the delay time the last measured
value is frozen. If the measured signal is received again in sufficient strength within the delay time, the

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unit continues to work in normal operation. If, however, it is not received again in sufficient strength
within the delay time, the unit passes into the alert mode and output OUT2 changes into the defined
state.
In case of heavy foam build-up and turbulence, consider the option of creating a steady area.
5.3.4 Simulation function
Various levels can be simulated for set-up, maintenance or interference reduction. The duration of the
simulation can be selected (1min...1h). The simulation can be started manually and runs until it is
stopped manually or the set time elapses. During the simulation the outputs respond according to the
simulated process values
5.3.5 Damping function
With unsteady level (e.g. turbulence, wave movements), the output response can be damped. During
damping the determined level values are smoothed by means of a mean filter; the result is a steady
curve.
Damping can be set by means of the parameter [dAP].
[dAP] indicates in seconds after what time 63 % of the final value is reached in the event of a sudden
jump. After 5x[dAP] almost 100 % has been reached.
5.4 Output response in different operating states
OUT1 OUT2*
Initialisation OFF OFF
Normal operation according to the level and [ou1] and
[SSC1...] settings
according to the level and [ou2], [ASP2]
and [AEP2] settings
Fault/ alert mode OFF <3.6mA at [FOU2] = [OFF]
>21mA at [FOU2] = [On]
* If analogue output [ou2] = [I] has been selected.
If the switching function has been selected: see column OUT1.
Additional information about the analogue output
Full signal With rising curve 20...20.5 mA
With dropping curve 4...3.8 mA
Empty signal With rising curve 4...3.8 mA
With dropping curve 20...20.5 mA
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6 Mounting
CAUTION
With high process temperatures, parts of the unit may heat up.
wRisk of burns
uDo not touch the unit.
uProtect the housing against contact with flammable substances and unintentional
contact.
uAllow the unit and process adapter to cool down before maintenance.
Careful handling of the antenna
uBe careful not to scratch or otherwise damage the antenna.
Before installing and removing the unit:
uMake sure that no pressure is applied to the system. Also always take into account the
potential dangers related to extreme machine and medium temperatures.
uBefore installing the unit, observe the following mounting specifications.
6.1 Mounting position
The unit is a TLPR device. TLPR (Tank Level Probing Radar) equipment are devices for level
measurement in a closed space only (i.e. metallic, reinforced concrete or fibreglass tanks, or
similar enclosure structures made of comparable attenuating material).
uUse preferably in metal tanks. When used in electrically non-conductive tanks: Non-metallic
tanks (Ò/15)
uFurther requirements: ETSI EN 302 372 (TLPR), Annex E
uObserve the following when selecting the mounting position:
• For optimal performance, the unit should be installed in locations with a clear and unobstructed
view of the medium surface.
• The unit should be mounted with as few internal structures as possible within the signal beam.
• Do not mount the unit close to or above the inlet stream (Ò Fig. Mounting).
• Do not position the unit directly above a side manway door.
D
Fig.6: Mounting
uDistance to wall (D): Dmin = 200 mm (8 inch).
uRecommended: ½ of tank radius.

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6.2 Inclination
90°
1
Fig.7: Inclination
uMount the unit vertically (90°) to ensure a good echo from the
medium surface.
uMaximum inclination (1): 3° (Fig. Inclination).
6.3 Non-metallic tanks
Non-metallic tanks are, for example, fibreglass tanks.
Nearby objects outside the tank may cause disturbing radar echoes as such materials may
allow radar waves to pass through. Corrective measures:
uThe unit should be positioned so that objects close to the tank are kept outside the signal
beam.
When installed in non-metallic tanks, there may be deterioration caused by electromagnetic
interference from other devices. Corrective measures:
uApply a shielding screen/ metal foil between the level sensor and other electrical devices.
uAdditional installation in a metal pipe. Consider the beam angle of the unit when selecting a
pipe diameter.
6.4 Beam angle and beam width
uMount the unit with as few internal structures as possible within the signal beam.
D
W
α
Fig.8: Beam angle and beam width
Beam angle (α): 10°
Beam width (W) as a function of the distance (D):
Distance (D) Beam width (W)
2 m (6.6 ft.) 0.4 m (1.2 ft.)
4 m (13.1 ft.) 0.7 m (2.3 ft.)
6 m (19.7 ft.) 1.1 m (3.5 ft.)
8 m (26.2 ft.) 1.4 m (4.6 ft.)
10 m (32.8 ft.) 1.8 m (5.8 ft.)
The signal beam may penetrate the side wall of non-metallic tanks (e.g. fibreglass tanks).
wSuch materials are largely transparent to the radar signal. Nearby objects outside the tank
may cause disturbing radar echoes.
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6.5 Nozzle requirements
uTo allow the radar waves to propagate undisturbed, the specified nozzle dimensions should be
observed (Ò Fig. Nozzle dimensions and table).
uThe inside of the nozzle must be smooth (i.e. avoid bad welding, rust, or deposit).
D
H
Fig.9: Nozzle dimensions
Maximum nozzle height (H) as a function of the nozzle diameter (D):
Nozzle diameter (D) Nozzle height (H)
40 mm (1.5 in.) 150 mm (5.9 in.)
50 mm (2 in.) 200 mm (7.9 in.)
80 mm (3 in.) 300 mm (11.8 in.)
100 mm (4 in.) 400 mm (15.8 in.)
150 mm (6 in.) 600 mm (23.6 in.)
6.6 Notes for hygienic applications
The unit withstands standard CIP routines and SIP routines up to 140°C.
uTo conform with applicable hygienic standards and food and beverage legislation and regulations,
make sure:
– the unit is installed in a closed tank.
– the unit is installed with hygienic adapter and O-ring/seal.
uIt is the responsibility of the user to ensure:
– the materials used (Ò Data sheet) are suitable for the media to be detected and the cleaning/
sanitising processes.
– the installation of the unit is drainable and cleanable.
– that the joint/clamping between the unit and the nozzle is compatible with the tank pressure and
media.
– that for the application an M12 connector with appropriate ingress protection against dirt and
moisture is used.
6.6.1 Notes on the use according to EHEDG
The unit is suited for CIP (cleaning in process) when installed correctly.
uObserve the application limits (temperature and material resistance) according to the data
sheet.
uEnsure that the installation of the unit in the system complies with EHEDG guidelines.
uUse self-draining installation.
uOnly use process adapters permitted according to EHEDG with special seals required by the
EHEDG position paper.
The gasket of the system interface must not be in contact with the sealing point of the sensor.
uIn case of structures in a tank, the installation must be flush mount. If not possible then direct water
jet cleaning and cleaning of dead spaces must be possible.
uInstall leakage ports so that they are clearly visible.

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1
d
D
L
2
1: Leakage port
2: Seal
uTo avoid dead space adhere to the dimensions:
L<(D - d)
d = 25 mm
6.6.2 Notes on the use according to 3-A®
uMake sure that the sensor is integrated into the system according to 3-A.
uUse only adapters with 3-A qualification and marked with the 3-A symbol. Available accessories:
www.ifm.com.
The process connection must be provided with a leakage port. This is ensured when installed using
adapters with 3-A approval.
uInstall leakage ports so that they are clearly visible.
uIt is recommended to choose an installation position where the probe and the process connection
can be cleaned with a spray ball.
For use according to 3-A, special regulations apply for cleaning and maintenance.
Not suitable for systems that have to meet the criteria of E9.2 of the 3A standard 63-04.
6.7 Mounting in a threaded connection
A
Fig.10: Threaded mounting
Thread length requirements (A) for the G1 process connection on the
tank:
Required thread length (A)
Amin 8 mm (0.32 in.)
Amax 16 mm (0.63 in.)
6.8 Mounting preparations
6.8.1 Remove the protective cap
The protective cap protects the antenna from impacts during transport and storage.
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uBefore installing, carefully remove the protective cap.
uBe careful not to scratch or otherwise damage the antenna.
6.8.2 Place the O-ring, grease the thread
The matching O-ring (EPDM) is supplied with the adapter. More O-rings are available as
accessories.
uPlace the O-ring in the groove of the unit.
uLightly grease the thread of the unit with lubricating paste.
The paste must be approved for the application and compatible
with the elastomers used.

Electronic level sensor LW2720
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6.8.3 Premount the adapter for pipe fittings
uSlide the coupling nut up over the bottom of the unit.
uMake sure that the O-ring is mounted in the groove of the unit.
uScrew the adapter onto the unit until it is hand-tight.
uSecure the unit and adapter using a vice.
Use suitable vice jaws (protectors). Do not over-tighten the vice
as it might damage the adapter.
39 mm
uTighten firmly. Recommended tightening torque: 35 Nm.
Further tightening may affect the sealing. Replace the O-ring or
the entire process connection if the seal area is damaged.
6.8.4 Install the welding aid
Install the welding aid:
The welding aid absorbs heat during the welding process and can prevent warping of the weld-in
adapter.
GB

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CAUTION
During the welding operation, the adapter and the welding aid can increase in temperature
to over 65°C (149°F).
wRisk of burns
uLet the components of the welding aid and weld-in adapter cool down before removal.
uHand-tighten the weld-in adapter on the welding aid.
uInsert the clamping bolt through welding aid opening.
uMount the counter plate.
16 mm
uHand-tighten the nut.
Weld the weld-in adapter to the tank: