WIKA FLRU-SFI User manual

Operating instructions
Betriebsanleitung
EN
DE
Reed-Füllstandstransmitter zum Anschluss an
WIKA-Funkeinheit, Typ FLRU-SFI
Reed level transmitter for connection to WIKA radio unit,
model FLRU-SFI
FLRU-SFI

2
14609053.01 07/2023 EN/DE
WIKA operating instructions, model FLRU-SFI
EN
DE
© 07/2023 WIKA Alexander Wiegand SE & Co. KG
All rights reserved. / Alle Rechte vorbehalten.
WIKA®is a registered trademark in various countries.
WIKA®ist eine geschützte Marke in verschiedenen Ländern.
Prior to starting any work, read the operating instructions!
Keep for later use!
Vor Beginn aller Arbeiten Betriebsanleitung lesen!
Zum späteren Gebrauch aufbewahren!
Operating instructions model FLRU-SFI Page 3 - 34
Betriebsanleitung Typ FLRU-SFI Page 35 - 66

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Contents
Contents
1. General information 4
2. Design and function 5
2.1 Overview. . . . . . . . . . . . . . . . . . . . . . . . 5
2.2 Description . . . . . . . . . . . . . . . . . . . . . . . 6
2.3 Scope of delivery . . . . . . . . . . . . . . . . . . . . . 6
2.4 Product passport . . . . . . . . . . . . . . . . . . . . . 6
3. Safety 7
3.1 Explanation of symbols . . . . . . . . . . . . . . . . . . . 7
3.2 Intended use . . . . . . . . . . . . . . . . . . . . . . 8
3.3 Improper use . . . . . . . . . . . . . . . . . . . . . . 9
3.4 Responsibility of the operator . . . . . . . . . . . . . . . . . 10
3.5 Personnel qualification . . . . . . . . . . . . . . . . . . . 10
3.6 Personal protective equipment . . . . . . . . . . . . . . . . 11
3.7 Labelling, safety marks . . . . . . . . . . . . . . . . . . .12
3.8 Ex marking . . . . . . . . . . . . . . . . . . . . . . . 13
3.9 Special conditions for installation and operation (X conditions) . . . . . 15
3.10 Specifications and temperature limits . . . . . . . . . . . . . .15
3.11 Certified WIKA radio unit, model NETRIS®3 . . . . . . . . . . . 15
4. Transport, packaging and storage 16
4.1 Transport. . . . . . . . . . . . . . . . . . . . . . . . 16
4.2 Packaging and storage . . . . . . . . . . . . . . . . . . .16
5. Commissioning, operation 17
5.1 Mechanical mounting . . . . . . . . . . . . . . . . . . . 19
5.2 Electrical connection, digital output . . . . . . . . . . . . . . .21
5.3 Commissioning . . . . . . . . . . . . . . . . . . . . . 22
6. Faults 22
7. Maintenance, cleaning and calibration 24
7.1 Maintenance . . . . . . . . . . . . . . . . . . . . . . 24
7.2 Cleaning . . . . . . . . . . . . . . . . . . . . . . . .25
8. Dismounting, return and disposal 26
8.1 Dismounting . . . . . . . . . . . . . . . . . . . . . . 26
8.2 Return. . . . . . . . . . . . . . . . . . . . . . . . . 27
8.3 Disposal . . . . . . . . . . . . . . . . . . . . . . . .27
9. Specifications 28
10. Accessories 32
Annex : EU declaration of conformity 33

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1. General information
1. General information
■The instrument described in the operating instructions has been manufactured
using state-of-the-art technology. All components are subject to stringent quality and
environmental criteria during production. Our management systems are certified in
accordance with ISO 9001 and ISO 14001.
■These operating instructions contain important information on handling the instrument.
Working safely requires that all safety instructions and work instructions are observed.
■Observe the relevant local accident prevention regulations and general safety regula-
tions for the instrument's range of use.
■The operating instructions are part of the product and must be kept in the immediate
vicinity of the instrument and readily accessible to skilled personnel at any time. Pass
the operating instructions on to the next operator or owner of the instrument.
■Skilled personnel must have carefully read and understood the operating instructions
prior to beginning any work.
■In case of a different interpretation of the translated and the English operating instruc-
tions, the English wording shall prevail.
■The general terms and conditions contained in the sales documentation shall apply.
■Subject to technical modifications.
■Further information:
- Internet address: www.wika.de / www.wika.com
- Relevant data sheet: LM 20.13
- Additional documentation: Special documentation LoRaWAN®communication
specification, article number 14622627
- Contact: Tel.: [phone]
[e-mail]
Supplementary documentation:
▶Please follow all the documentation included within the scope of delivery.
Before commissioning the instrument, the operating instructions for the
WIKA model NETRIS®3 radio unit, article number 14521664, must also
be observed!

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2. Design and function
2.1 Overview
1Coupler connector
2Electronic unit
3Mounting thread
4Guide tube
5Float
6Adjusting collar






1. General information / 2. Design and function
Abbreviations, definitions
■Bullet
▶Instruction
1. ... x. Follow the instruction step by step
→See ... cross-references
UWI Unified WIKA Interface

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2.2 Description
Level transmitters work on the float principle with magnetic transmission. A permanent
magnet built into the float triggers, with its magnetic field, the resistance measuring chain
built into the guide tube.The entire assembly corresponds to a 3-wire potentiometer
circuit.The float changes its height with the level of the medium it is monitoring.The
measured resistance signal is proportional to the level.The measurement voltage is very
finely stepped due to the contact separation of the resistance measuring chain and is
thus virtually continuous.
Ex version
The model FLRU-SFI is suitable for use in hazardous areas.
2.3 Scope of delivery
Cross-check scope of delivery with delivery note.
2.4 Product passport
The product passport is a web application where various information about an instrument
can be retrieved by entering the 11-digit alphanumeric serial number. This includes, for
example, instrument configuration, article number, operating instructions and data sheet.
The product passport can be retrieved from the product page or directly from the corre-
sponding web application.
Web application
2. Design and function

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3. Safety
3.1 Explanation of symbols
DANGER!
... indicates a directly dangerous situation resulting in serious injury or death,
if not avoided.
WARNING!
... indicates a potentially dangerous situation that can result in serious injury
or death, if not avoided.
CAUTION!
... indicates a potentially dangerous situation that can result in light injuries or
damage to property or the environment, if not avoided.
WARNING!
... indicates a potentially dangerous situation that can result in burns, caused
by hot surfaces or liquids, if not avoided.
DANGER!
... indicates a potentially dangerous situation in the hazardous area that can
result in serious injury or death, if not avoided.
Information
... points out useful tips, recommendations and information for efficient and
trouble-free operation.
3. Safety

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3.2 Intended use
The model FLRU-SFI features an integrated transmitter with electronic signal process-
ing and is prepared for connection to the WIKA model NETRIS®3 radio unit.The instru-
ment is used for measuring the level in hazardous areas of industrial applications. Level
transmitters of this model series can be mounted directly into the process.The instru-
ment offers many application possibilities for liquid, aggressive media that are not highly
viscous or crystallising. All electrical components are protected against humidity and
designed to be vibration-resistant.The electrical connection is made via an M12 x 1
circular connector.
The model FLRU-SFI level transmitter in combination with the model NETRIS®3 radio
unit is used wherever web-based remote monitoring of the fill level is desired in addition
to on-site indication.
Only use the instrument in applications that lie within its technical performance limits. A
change in the ambient temperature can lead to a fault in the instrument function due to
the formation of condensation. Before putting it back into operation, wait for the instru-
ment temperature and the room temperature to equalise.
The operator of the plant in which the product is used must ensure the compatibility of the
materials of the wetted parts with the medium used.
The instrument must only be used with media which are not harmful to the wetted parts
over the entire range of use of the instrument.
Any change in the state of the matter or any decomposition of unstable media is not
permitted.
Do not operate the instrument in the direct vicinity of ferromagnetic environments (min.
clearance 50 mm [1.96 in]).
The instrument has been designed and built solely for the intended use described here,
and may only be used accordingly.
The technical specifications of the enclosed operating instructions and the operating
instructions for the NETRIS®3 radio unit must be observed. Improper handling or opera-
tion of the instrument outside of its technical specifications requires the instrument to be
taken out of service immediately and inspected by an authorised WIKA service engineer,
see chapter 9 “Specifications”. The manufacturer shall not be liable for claims of any type
based on operation contrary to the intended use.
Certificates and applied standards
EU-type examination certificate Certificate IECEx
BVS 23 ATEX E 012 X
EN IEC 60079-0:2018
IEC 60079-11:2023
IEC 60079-26:2021
IECEx BVS 23.0006X
IEC 60079-11:2017 (7th edition)
IEC 60079-11:2023 (7th edition)
IEC 60079-26:2021(4th edition)
3. Safety

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Assembly
For the application limits of the assembly, compliance with the specifications of the WIKA
radio unit and the specifications of the model FLRU-SFI is required.The permissible
ambient temperature range of the assembly is determined by the instrument with the
lowest temperature range.
DANGER!
Injuries through improper use
Failure to follow instructions for the assembly can result in death or serious
injury.
▶Assessment of operability by skilled personnel.
The remote monitoring of the level via radio transmission is only suitable for non-critical
and non-safety-relevant applications.
The remote monitoring function must not be used for control purposes, as it
cannot be guaranteed that data packets won't be lost during radio transmis-
sion.
3.3 Improper use
WARNING!
Changes to the instrument
Changes to the instrument can lead to hazardous situations and injuries.
▶Refrain from unauthorised modifications or changes to the instrument.
▶The instrument must only be used for the usage described here.
▶Only use the approved radio unit, see chapter
3.11 “Certified WIKA radio unit, model NETRIS®3”.
▶The maximum cable length of 3 m [9.8 ft] to the radio unit must be
observed.
WARNING!
Injuries through improper use
Improper use of the instrument can lead to hazardous situations and injuries.
▶Once the instrument has been assembled, do not carry it by the radio unit.
▶Do not use the instrument for abrasive and highly viscous or crystallising
media.
The instrument must not be used as part of a safety or emergency shutdown device
(safety accessory).
Protection against external impact
Avoid any kind of external impact. External impacts can generate sparks through friction
processes between different materials.
3. Safety

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Explosive atmosphere consisting of hybrid mixtures
The instruments must not be used in areas in which an atmosphere consisting of explo-
sive hybrid mixtures (dusts mixed with gases) can occur.
Handling of materials
Avoid exposing the instrument to any substances or ambient conditions that could
negatively affect the instrument and the materials used. Avoid handling substances that
are liable to spontaneous combustion. For a list of the materials used, see chapter 9
“Specifications”.
3.4 Responsibility of the operator
The instrument is used in the industrial sector.The operator is therefore responsible for
legal obligations regarding safety at work.
The safety instructions within these operating instructions, as well as the safety, accident
prevention and environmental protection regulations for the application area must be
maintained.
The operator is obliged to maintain the product label in a legible condition.The legibility of
the marking must be observed during time in use but at least during inspection periods of
three years. If any harm of the legibility is found please contact the manufacturer to renew
the marking.
To ensure safe working on the instrument, the operating company must ensure
■that suitable first-aid equipment is available and aid is provided whenever required.
■that the operating personnel are regularly instructed in all topics regarding work safety,
first aid and environmental protection and know the operating instructions and, in
particular, the safety instructions contained therein.
■that the instrument is suitable for the particular application in accordance with its
intended use.
■that personal protective equipment is available.
Any use beyond or different to the intended use is considered as improper use.
3.5 Personnel qualification
WARNING!
Risk of injury should qualification be insufficient
Improper handling can result in considerable injury and damage to property.
▶The activities described in these operating instructions may only be
carried out by skilled personnel who have the qualifications described
below.
▶Keep unqualified personnel away from hazardous areas.
3. Safety

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Skilled electrical personnel
Skilled electrical personnel are understood to be personnel who, based on their techni-
cal training, know-how and experience as well as their knowledge of country-specific
regulations, current standards and directives, are capable of carrying out work on electri-
cal systems and independently recognising and avoiding potential hazards.The skilled
electrical personnel have been specifically trained for the work environment they are
working in and know the relevant standards and regulations.The skilled electrical person-
nel must comply with current legal accident prevention regulations.
Special knowledge for working with instruments for hazardous areas:
The skilled personnel must have knowledge of ignition protection types, regulations and
provisions for equipment in hazardous areas.
WARNING!
Special hazards with hazardous media
Upon contact with hazardous media, e.g. oxygen, acetylene, flammable
or toxic substances, there is a danger of physical injuries and damage to
property and the environment.
▶For these media, in addition to all standard regulations, the appropriate
existing codes or regulations must also be followed.
3.6 Personal protective equipment
The personal protective equipment is designed to protect the skilled personnel from
hazards that could impair their safety or health during work.When carrying out the various
tasks on and with the instrument, the skilled personnel must wear personal protective
equipment.
Follow the instructions displayed in the work area regarding personal protective
equipment!
The requisite personal protective equipment must be provided by the operating company.
3. Safety

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Symbols
Before mounting and commissioning the instrument, ensure you read the operating
instructions!
Do not dispose of with household waste. Ensure a proper disposal in accord-
ance with national regulations.
Hot surface! Instrument can become hot.
3.7 Labelling, safety marks
Product label, model FLRU-SFI (example)
1Model
2Date of manufacture (year-month)
3Approval-related data
4Serial number, TAG number, information on
the version
3. Safety

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3. Safety
3.8 Ex marking
DANGER!
Loss of explosion protection
Non-observance of additional safety instructions may result in the loss of
explosion protection
▶Follow the requirements of the ATEX directive
▶Additionally follow the specifications of the respective national regulations
concerning Ex usage (e.g. EN 60079-10 and EN 60079-14)
The FLRU-SFI level transmitters are approved as explosion-protected equipment within
the scope of the EC directive 2014/34/EU and IECEx scheme for use in hazardous areas.
They meet the requirements for electrical equipment for hazardous areas.
Float and guide tube may be in zone 0.
The specifications in the chapter (link) in these operating instructions must be observed.
■The responsibility for classification of zones lies with the plant manager and not the
manufacturer/supplier of the equipment.
■The plant operator guarantees, and is solely responsible, that all level transmitters in
use are identifiable with respect to all safety-relevant characteristics. Damaged level
transmitters may not be used.
■Electrical screening may only be grounded at one end, and outside of the Ex area.
Special cases are described in DIN EN 60079-14:2003.
■A galvanic isolation must exist between the intrinsically safe and non-intrinsically safe
circuits.
■At the container, there is danger of an explosive atmosphere. Corresponding measures
for preventing sparking should be taken. No work is allowed in this area unless by
technically skilled staff in accordance with applicable safety regulations.

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3. Safety
Hazardous gas
atmosphere
Tempe-
rature
class
Ambient temperature
range (Ta)
Process temperature
II 1G Ex ia IIC T1 -
T6 Ga
II 1/2G Ex ia IIC T1 -
T6 Ga/Gb
II 2G Ex ia IIC T1 - T6
Gb
T6 -40 ... +50 °C
[-40 ... +122 °F]
-80 ... +71.5 °C
[-112 ... +160.7 °F]
T5 -40 ... +75 °C
[-40 ... +167 °F]
-80 ... +86.5 °C
[-112 ... +187.7 °F]
T4 -40 ... +105 °C
[-40 ... +221 °F]
-80 ... +121.5 °C
[-112 ... +250.7 °F]
T3 -40 ... +105 °C
[-40 ... +221 °F]
-80 ... +186.5 °C
[-112 ... +367.7 °F]
T2 -40 ... +105 °C
[-40 ... +221 °F]
-80 ... +200 °C
[-112 ... +392 °F]
T1 -40 ... +105 °C
[-40 ... +221 °F]
-80 ... +200 °C
[-112 ... +392 °F]
Hazardous dust/air
atmospheres
Power PiAmbient tempe-
rature range (Ta)
Process temperature
II 1D Ex ia IIIC T* Da
II 1/2D Ex ia IIIC T* Da/Db
II 2D Ex ia IIIC T* Db
330 mW -40 ... +100 °C
[-40 ... 212 °F]
-80 ... +200 °C
[-112 ... +392 °F] - 9 K 1)
1) Please take a self heating of 9 K into consideration.

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3.9 Special conditions for installation and operation (X conditions)
1. A heat input (e.g. heat return from the process or radiant heat from the environ-
ment) which exceeds the permissible ambient temperature of the housing is not
permissible and must be prevented either by suitable thermal insulation or by an
appropriately long housing elevation or by suitable on-site measures.
The heat input must be determined by calculation or by measurement by the user.
2. In dust-explosive areas, the device shall be installed in such a way that electrosta-
tic charging at the type label is excluded.
3. In dust-explosive areas with conductive dust IIIC, the intrinsically safe circuit is not
safely separated from earth/potentially earthed metal parts.
Along the intrinsically safe circuit, potential equalization must exist.
3.10 Specifications and temperature limits
Temperature load
When mounting the instrument it must be ensured that, taking into consideration the
influence of convection and heat radiation, no deviation above or below the permissible
ambient and medium temperatures can occur.
The permissible temperature ranges must not be exceeded at the instrument either. If
necessary, measures for cooling have to be taken.
3.11 Certified WIKA radio unit, model NETRIS®3
Only the NETRIS®3 certified radio unit is approved for connection to the FLRU-SFI level
transmitter with digital interface. No other radio unit may be used for an assembly.
→For a detailed description of the battery-operated, certified instrument, see the operat-
ing instructions for the model NETRIS®3, article number 14521664!
DANGER!
Danger to life due to loss of explosion protection
In addition, observe the Ex marking of the connected radio unit.
▶Only use the certified radio unit!
3. Safety

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4. Transport, packaging and storage
4.1 Transport
Check the level transmitter for any damage that may have been caused.
Obvious damage must be reported immediately.
CAUTION!
Damage through improper transport
With improper transport, a high level of damage to property can occur.
▶Once the instrument has been assembled, do not carry it by the radio unit!
▶When unloading packed goods upon delivery as well as during internal
transport, proceed carefully and observe the symbols on the packaging.
▶With internal transport, observe the instructions in chapter 4.2 “Packaging
and storage”.
4.2 Packaging and storage
Do not remove packaging and other protective elements (e.g. protective cap) until just
before commissioning. Make sure that this is done in a non-hazardous area and in a dry
environment.
Permissible conditions at the place of storage:
Storage temperature: -40 ... +85 °C [-40 ... +185 °F]
Humidity: 5 ... 95 % relative humidity (non-condensing)
Avoid exposure to the following factors:
■Direct sunlight or proximity to hot objects
■Mechanical vibration, mechanical shock (putting it down hard)
■Soot, vapour, dust and corrosive gases
Store the instrument in its original packaging in a location that fulfils the conditions
listed above. If the original packaging is not available, pack and store the instrument as
described below:
1. Wrap the instrument in an anti-static plastic film.
2. Place the instrument, along with the shock-absorbent material, in the packaging.
3. If stored for a prolonged period of time (more than 30 days), place a bag containing a
desiccant inside the packaging.
4. Transport, packaging and storage

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5. Commissioning, operation
Personnel: Skilled personnel
Before installation, commissioning and operation, ensure that the appropriate instrument
has been selected in terms of scale range, design, explosion protection and specific
measuring conditions.
Observe all instructions given on the shipment packaging for removing the transportation
safety devices, remove the level transmitter carefully from the packaging and check it for
any damage that may have been caused. Obvious damage must be reported immedi-
ately.
Information
Avoid putting any mechanical loading on the electrical connections and on
the cases. Connections must only be opened once the instrument has been
depressurised and has cooled down.
The FLRU-SFI level transmitter, ignition protection type Ex i, in Ex areas of zone 0/1 (float
and guide tube in zone 0), must only be connected to certified intrinsically safe control
circuits.The maximum operating data must be observed.
Instruments with powder coating, plastics or adhesive product labels > 500 mm2on metal
cases must not be used in areas in which there are processes that generate strong charg-
es, mechanical grinding or cutting processes, the spraying of electrons, e.g. in the vicinity
of electrostatic painting equipment, or pneumatically conveyed dust removal occurs.
Equipotential bonding
The instrument must be connected to the equipotential bonding of the plant.
Chemical reactions or self-igniting processes can only come from the medium itself,
not from the instrument.The danger of ignition of the medium itself must be taken into
account and prevented by the operator.
High or low temperatures and/or high pressures inside the vessel affect the safety param-
eters of the substances that occur. If pressures or temperatures in the non-atmospheric
range occur inside the vessel, then the operator must check for themself what influence
these conditions have on the safety-related parameters of the substances that occur, and
what direct ignition hazards result from this.
5. Commissioning, operation

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WARNING!
Physical injury
When commissioning, there is a danger from aggressive media and high
pressures.
▶Observe the information in the material safety data sheet for the corre-
sponding medium.
▶Before connecting to a vessel, pipeline or system, depressurise them.
WARNING!
Physical injuries and damage to property and the environment caused
by hazardous media
Upon contact with hazardous media (e.g. oxygen, acetylene, flammable or
toxic substances), harmful media (e.g. corrosive, toxic, carcinogenic, radio-
active), there is a danger of physical injuries and damage to property and
the environment. Should a failure occur, aggressive media with extremely
high temperature and under high pressure or vacuum may be present at the
instrument.
▶For these media, in addition to all standard regulations, the appropriate
existing codes or regulations must also be followed.
▶Wear the requisite protective equipment.
WARNING!
Physical injuries and damage to property and the environment caused
by media escaping under high pressure
With the pressurisation of the instrument, as a result of poor sealing of the
process connection, media under high pressure can escape. Due to the high
energy of the media that can escape in the event of a failure, the possibility of
physical injuries and damage to property exists.
▶The sealing of the process connection must be carried out expertly and
checked for leak tightness.
5. Commissioning, operation

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WARNING!
Damage to the instrument through electrostatic discharge
Improper handling of electrical components can damage or destroy them.
▶Before mounting, touch a grounded metal object (e.g. radiator, pipes).This
dissipates static charges from the body.
▶Only remove the protective cap of the connector immediately before instal-
lation in a non-hazardous area and in a dry environment, making sure that
there is sufficient ESD protection (e.g. ESD clothing). Do not touch the
pins of the now open connector.
5.1 Mechanical mounting
CAUTION!
Damage to the instrument
In order to prevent any damage to the instrument, observe the following:
▶The instrument must not be subjected to any mechanical loading (e.g. use
as a climbing aid, support for objects).
▶Make sure the threaded connections and sealing faces are clean and
undamaged.
▶Install the instrument in such a way that process-related electrostatic
charges (e.g. caused by flowing media) can be excluded.
▶The connector pins must not come into contact with any moisture.
Installation
■Observe the torque values of screws specified in pipefitting work.
■In the selection of the mounting material (sealings, screws, washers and nuts), take
the process conditions into account.The suitability of the sealing must be specified
with regard to the medium and its vapours. In addition, ensure it has corresponding
corrosion resistance.
■Mount the level transmitter either via mounting thread or mounting flange (not illus-
trated).
■The guide tube should not be inclined more than a maximum of 30° to the vertical.
■Select a tightening torque of 0.6 Nm for the M12 mating connector.
5. Commissioning, operation

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A Teflon disc on the float limitations prevents sparking if the float should fall on it.The use
of the instrument without this Teflon disc is not permitted, except for special variants for
gas group IIB without a Teflon disc.
If floats made of titanium are used, it must be ensured that these floats cannot generate
friction or impact sparks, even in rare cases.
In vessels where turbulence is to be expected, level transmitters with an approval in
accordance with the following table must also be secured against bending of the guide
tube.
Gb
Ga
≤ 30°
5. Commissioning, operation