WIKA FLM-CAI User manual

Operating instructions
Betriebsanleitung
EN
DE
Magnetostrictive level transmitter for hazardous areas,
models FLM-CAI, FLM-TAI, BLM-TAI
Magnetostriktiv-Füllstandstransmitter für explosionsgefährdete
Bereiche, Typen FLM-CAI, FLM-TAI, BLM-TAI
Mounting flange, spherical float from stainless steel, model FLM-CAI

EN
DE
2
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Operating instructions magnetostrictive level transmitter, models FLM-xAI, BLM-TAI (Ex)
Operating instructions models FLM-CAI, FLM-TAI,
BLM-TAI (Ex)
Page
3 - 36
Betriebsanleitung Typen FLM-CAI, FLM-TAI, BLM-TAI
(Ex)
Seite
37 - 70
© 09/2019 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!

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Operating instructions magnetostrictive level transmitter, models FLM-xAI, BLM-TAI (Ex) 3
Contents
Contents
1. General information 5
2. Design and function 5
2.1 Description . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2 Model overview . . . . . . . . . . . . . . . . . . . . . . 6
2.3 Construction and principle of operation . . . . . . . . . . . . . . 7
2.4 Scope of delivery . . . . . . . . . . . . . . . . . . . . . . 8
3. Safety 9
3.1 Explanation of symbols . . . . . . . . . . . . . . . . . . . . 9
3.2 Intended use . . . . . . . . . . . . . . . . . . . . . . . 9
3.3 Improper use . . . . . . . . . . . . . . . . . . . . . . 10
3.4 Responsibility of the operator . . . . . . . . . . . . . . . . . 10
3.5 Personnel qualification . . . . . . . . . . . . . . . . . . . 11
3.6 Personal protective equipment . . . . . . . . . . . . . . . . 11
3.7 Labelling, safety marks . . . . . . . . . . . . . . . . . . . 12
3.8 Ex marking . . . . . . . . . . . . . . . . . . . . . . . 12
4. Transport, packaging and storage 13
4.1 Transport. . . . . . . . . . . . . . . . . . . . . . . . 13
4.2 Packaging and storage . . . . . . . . . . . . . . . . . . . 13
5. Commissioning, operation 14
5.1 Mounting. . . . . . . . . . . . . . . . . . . . . . . . 14
5.1.1 “Screw-in body” version . . . . . . . . . . . . . . . . . 16
5.1.2 “Flange” version . . . . . . . . . . . . . . . . . . . 17
5.1.3 “Mounting on bypass” version. . . . . . . . . . . . . . . 17
5.2 Electrical connection. . . . . . . . . . . . . . . . . . . . 19
5.2.1 Connection diagram (Ex) . . . . . . . . . . . . . . . . 19
5.2.2 Cable length . . . . . . . . . . . . . . . . . . . . 20
5.2.3 Wiring with cable gland . . . . . . . . . . . . . . . . . 21
5.2.4 Wiring with M12 connector. . . . . . . . . . . . . . . . 22
5.3 Adjustment . . . . . . . . . . . . . . . . . . . . . . . 24
5.3.1 Measuring span on the level transmitter . . . . . . . . . . . 24
5.3.2 Current supply in error mode . . . . . . . . . . . . . . . 25
6. Safety-related characteristic values 26
7. Faults 28

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Operating instructions magnetostrictive level transmitter, models FLM-xAI, BLM-TAI (Ex)4
Contents
Declarations of conformity can be found online at www.wika.com.
8. Maintenance and cleaning 30
8.1 Maintenance . . . . . . . . . . . . . . . . . . . . . . 30
8.2 Cleaning . . . . . . . . . . . . . . . . . . . . . . . . 30
9. Dismounting, return and disposal 31
9.1 Dismounting . . . . . . . . . . . . . . . . . . . . . . 31
9.2 Return. . . . . . . . . . . . . . . . . . . . . . . . . 31
9.3 Disposal . . . . . . . . . . . . . . . . . . . . . . . . 31
10. Specifications 32
10.1 Model FLM-CAI . . . . . . . . . . . . . . . . . . . . . 32
10.2 Model FLM-TAI . . . . . . . . . . . . . . . . . . . . . 33
10.3 Model BLM-TAI . . . . . . . . . . . . . . . . . . . . . 34
10.4 Float . . . . . . . . . . . . . . . . . . . . . . . . . 34
Annex: EU declaration of conformity 36

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Operating instructions magnetostrictive level transmitter, models FLM-xAI, BLM-TAI (Ex) 5
1. General information
■
The magnetostrictive level transmitters described in the operating instructions have
been designed and manufactured using state-of-the-art technology. All components
are subject to stringent quality and environmental criteria during production. Our
management systems are certified to ISO 9001.
■
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
regulations 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.
■
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 20.04 (FLM-CAI)
LM 20.01 (FLM-TAI)
LM 10.05 (BLM-TAI)
2. Design and function
2.1 Description
The model FLM-CAI (with guide tube Ø 6 mm) and model FLM-TAI (with guide tube
Ø 12 mm) high-accuracy level transmitters are used for the continuous measurement
of the level of liquid media in vessels.The measurement procedure used exploits the
physical effect of magnetostriction and is largely independent of the temperature. It is used,
especially, where very precise level measurements are required, such as in the chemical
industry.
In these operating instructions, the FLM is described with cable connection on the side of
the probe head. As cable connection, an M12 cable gland (also with M16 adapter), an M12
connector or an M20 or ½ NPT female thread are possible. As a further variant, there is
an FLM with an M12 connector on the probe head cover. Model BLM-TAI can be used for
mounting to bypass chambers.
1. General information / 2. Design and function

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Operating instructions magnetostrictive level transmitter, models FLM-xAI, BLM-TAI (Ex)6
The level transmitter emits a 4 … 20 mA output signal, which is configured via buttons
within the probe head, or a digital output signal as HART®protocol.
Probe lengths of 100 mm to 6 m, as “Flex version” up to 10 m, and also various
temperature and pressure ranges are possible.
Available versions:
■
With screw-in body, welded or for step-free positioning
■
With flange process connection
■
For mounting on a bypass with magnetic float
■
With 90° angled probe head
■
With 6 mm guide tube
■
With 6 mm guide tube and short cable bushing
■
With 12 mm guide tube
This level transmitter with ATEX approval can be installed in hazardous areas that require
electrical equipment of equipment protection level Ga (zone 0), equipment protection level
Ga/Gb (zone 0/1) or equipment protection level Gb (zone 1).
The instrument is designed in accordance with the following European standards:
EN IEC 60079-0:2018 Equipment – General requirements
EN 60079-11:2012 Device protection through intrinsic safety “i“
EN 60079-26:2015 Equipment of equipment protection level (EPL) Ga
2.2 Model overview
Model Guide tube diameter in mm Installation type
FLM-CAI 6 Direct installation
FLM-TAI 12 Direct installation
BLM-TAI 12 Bypass mounting
2. Design and function

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Operating instructions magnetostrictive level transmitter, models FLM-xAI, BLM-TAI (Ex) 7
2.3 Construction and principle of operation
The construction of the level transmitter is illustrated in the version with screw-in body. In
the probe head of the level transmitter are located the connection terminals and the
adjustment buttons protected by the cover .The electrical connection is made via an
M16 x 1.5 cable gland or M12 plug connection on the top of the probe head and the
ground connection at the bottom of the probe head (see chapter 5.1 “Mounting” and 5.3
“Adjustment”).
On the guide tube , for highly-adjustable mounting in the vessel, there is a screw-in
body (compression fitting) or, for fixed mounting, a flange (not shown).The float is
used for the continuous measurement of the product filling height or interface layer and is
held on the guide tube by an adjusting collar .
The “BLM for bypass mounting” version is delivered without process connection and float.







2. Design and function

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Operating instructions magnetostrictive level transmitter, models FLM-xAI, BLM-TAI (Ex)8
The measurement procedure shown in the following figure exploits the physical effect of
magnetostriction and is largely independent of the temperature. In the guide tube, a wire 
from magnetostrictive material is stretched. Via the sensor electronics, current pulses 
are sent through the wire, which generate a circular magnetic field . A magnet , which
is built into the float, acts as the level pick-up. Its magnetic field magnetises the wire axially.
Through the interference of the two magnetic fields, in the area of the float magnet, a
torsion wave is generated, which runs in both directions along the wire. One wave runs
directly to the probe head, the other is reflected off the lower end of the guide tube.The
time between the sending of the current pulse and the arrival of the wave at the probe head
is measured. From the time elapsed, the float position is determined.
2.4 Scope of delivery
Cross-check scope of delivery with delivery note.






2. Design and function

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Operating instructions magnetostrictive level transmitter, models FLM-xAI, BLM-TAI (Ex) 9
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.
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.
3.2 Intended use
Magnetostrictive level transmitters are used exclusively for the continuous measurement of
the level of liquid media in vessels.
The level transmitters are designed as intrinsically safe equipment and are suitable for use
in hazardous areas. All level transmitters can be used for all gases of group IIA, IIB and IIC.
In addition, all level transmitters may be used for the dust groups IIIA, IIIB and IIIC.
If a non-conductive plastic float is to be used in hazardous areas with gases of group IIC,
the danger due to static charging must be prevented. Observe the following conditions:
■
The float must not be used in strongly flowing, non-conductive liquids.
■
There must be no stirrer in the tank.
■
Frictions on non-conductive components must be avoided.
■
The float must not be cleaned dry.
3. Safety

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Operating instructions magnetostrictive level transmitter, models FLM-xAI, BLM-TAI (Ex)10
The instrument has been designed and built solely for the intended use described here,
and may only be used accordingly.
The manufacturer shall not be liable for claims of any type based on operation contrary to
the intended use.
3.3 Improper use
Improper use is defined as any application that exceeds the technical performance limits.
WARNING!
Injuries through improper use
Improper use of the instrument can lead to hazardous situations and injuries.
▶
Refrain from unauthorised modifications to the instrument.
Any use beyond or different to the intended use is considered as improper use.
Do not use this instrument in safety or emergency stop devices.
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.
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.
3. Safety

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Operating instructions magnetostrictive level transmitter, models FLM-xAI, BLM-TAI (Ex) 11
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.
Skilled personnel
Skilled personnel, authorised by the operator, are understood to be personnel who, based
on their technical training, knowledge of measurement and control technology and on
their experience and knowledge of country-specific regulations, current standards and
directives, are capable of carrying out the work described and independently recognising
potential hazards.
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.
Special operating conditions require further appropriate knowledge, e.g. of aggressive
media.
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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Operating instructions magnetostrictive level transmitter, models FLM-xAI, BLM-TAI (Ex)12
3.7 Labelling, safety marks
Product label
Model
Model code
Serial number
Article number
Tag no.
Ex-relevant data
Year of manufacture
Before mounting and commissioning the instrument, ensure you read the
operating instructions!
3.8 Ex marking
DANGER!
Danger to life due to loss of explosion protection
Non-observance of these instructions and their contents may result in the loss
of explosion protection.
▶
Observe the safety instructions in this chapter and further explosion
instructions in these operating instructions.
▶
Observe the information given in the applicable type examination certificate
and the relevant country-specic regulations for installation and use in
hazardous areas (in Germany these are the explosion protection ordinance
(ExVo), the operational safety ordinance (BetrSichV), the product safety act
and the special requirements of the EC-type examination certicate).
Check whether the classification is suitable for the application. Observe the relevant
national regulations.
Level sensor FLM
Type:
Ser. No.:
Art. No.:
Tag. No.:
IP68 max. DC 15 ... 30 V
4 ... 20 mA
WIKA Alexander Wiegand SE & Co. KG
Alexander-Wiegand-Strasse 30
63911 Klingenberg
WIKA Alexander Wiegand SE & Co. KG
Alexander-Wiegand-Strasse 30
63911 Klingenberg
Level Sensor ???????
T
ype: ???-????????????????
????????????????
4-20 mA
TÜV 18 ATEX 225120 X
I
I 1/2 G Ex ia IIC T6…T3 Ga/Gb
II 1 D Ex ia IIIC T160°C Da
0637
Ui=<30V; Pi=<1W; li=<200mA; Ci=<10nF; Li=<20µH
Bj.:????







3. Safety

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Operating instructions magnetostrictive level transmitter, models FLM-xAI, BLM-TAI (Ex) 13
II 1G Ex ia IIC T6 ... T4 Ga
II 1/2G Ex ia IIC T6 ... T4 Ga/Gb
II 2G Ex ia IIC T6 ... T4 Gb
II 1D Ex ia IIIC T160 °C Da
Special conditions for use (X conditions)
1. When using floats from titanium, the ignition hazard caused by impact or friction must be
avoided.
2. If plastic floats are used, there is a risk of ignition due to electrostatic discharges.The
operating instructions of the manufacturer must be followed.
4. Transport, packaging and storage
4.1 Transport
Check the instrument for any damage that may have been caused by transport.
Obvious damage must be reported immediately.
CAUTION!
Damage through improper transport
With improper transport, a high level of damage to property can occur.
▶
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 5.2 “Packaging
and storage”.
4.2 Packaging and storage
Do not remove packaging until just before mounting.
Keep the packaging as it will provide optimum protection during transport (e.g. change in
installation site, sending for repair).
3. Safety / 4. Transport, packaging and storage

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Operating instructions magnetostrictive level transmitter, models FLM-xAI, BLM-TAI (Ex)14
5. Commissioning, operation
DANGER!
Danger to life from explosion!
Through working in flammable atmospheres, there is a risk of explosion which
can cause death.
▶
Only carry out set-up work in non-hazardous environments!
DANGER!
Risk of injury due to improper use
Work on containers involves the danger of intoxication and suffocation.
▶
No work is allowed to be carried out unless by taking suitable personal
protective measures (e.g. breathing apparatus, protective clothing etc.).
▶
Work on the instrument must only be carried out by trained skilled
personnel.
5.1 Mounting
Guide tube length
Guide tube length
Insertion length
Guide tube
Screw-in body Flange Mounting on bypass
Probe head Probe head
Neck tube
Flange
Screw-in
body
112 112 116
Float Float
Adjusting
collar
Adjusting
collar
Guide tube
88
5. Commissioning, operation

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Operating instructions magnetostrictive level transmitter, models FLM-xAI, BLM-TAI (Ex) 15
■
During mounting, ensure that the guide tube is not bent and that the float is not
subjected to shock loads.
■
The installation of the level transmitter in areas with strong external magnetic fields is
not permitted, since this will impede the correct measured value determination.
■
The level transmitter can also be installed in the vessel from below. If the vessel is also
pressurised, then the maximum length of the level transmitter is 2 m.
■
If, during mounting, the float is removed, it must be slid back onto the guide tube with
the marking “TOP” in the direction of the probe head, so that correct measurement can
be made.
Information for safe mounting
The mounting should only be carried out in an unpowered state!
Prior to installation, it may be necessary to remove the float(s). When assembling, make
sure that the float(s) is/are mounted in the correct position on the sensor tube.
Only the sensor head of the ...LM-...I model with screw terminals should be opened.
Information for safe installation
The installation should only be carried out in an unpowered state. Observe special
regulations, e.g. EN 60079-14 or the local installation regulations.
If the level transmitter is supplied with a screw-in body, the thread of the screw-in body
must be provided with suitable sealing material, screwed into the existing bushing and
tightened. If the level transmitter is supplied without process connection, the operator is
responsible for compliance with the Ex requirements.
General note (see also EN 60079-26, section 4.3)
If the level transmitter is installed in the separating wall between zone 0 and zone 1, a
sufficiently tight gap (IP66 or IP67) must be ensured after installation.
The process connection may cause an opening in the separating wall to the area requiring
EPL “Ga“. There is then a risk of flammable gases being released and flames breaking
through.
5. Commissioning, operation

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Operating instructions magnetostrictive level transmitter, models FLM-xAI, BLM-TAI (Ex)16
5.1.1 “Screw-in body” version
The dismounting of the float is then only required if the float cannot pass
through the mounting hole in the vessel. Otherwise, only mounting steps 3, 6
and, if necessary, 7 must be carried out.
Inserting the level transmitter into the vessel:
1. Loosen both threaded pins, remove the adjusting collar and remove the float from
the guide tube .
2. If necessary, slide the screw-in body onto the guide tube.
3. Insert the level transmitter into the vessel, apply suitable sealing material to, screw in
and tighten the mounting thread .
4. Slide the float back onto the guide tube .
The float must be slid back onto the guide tube with the marking “TOP” in the
direction of the probe head, so that correct measurement can be made.
5. Re-affix the adjusting collar , position and secure the threaded pins over the groove.
6. Position the process connection to its height and tighten the union nut finger-tight by
hand.
7. Secure the union nut with a spanner through a 1 ¼ turn (see following figure).





Securing the compression fitting

5. Commissioning, operation

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Operating instructions magnetostrictive level transmitter, models FLM-xAI, BLM-TAI (Ex) 17
5. Commissioning, operation
5.1.2 “Flange” version
The guide tube is firmly welded to the flange, so the insertion length cannot be changed.
Secure the flange and the flange sealing with the flange screws and nuts.The screws, nuts
and seals are the responsibility of the operator and should be chosen dependent upon the
measuring medium.The fixing equipment and sealings must fulfil the requirements of the
EN 1092-1, EN 1514 and EN 1515 standards.
Should the float be unable to pass through the mounting hole, see mounting instructions,
chapter 5.1.1 ““Screw-in body” version”.
5.1.3 “Mounting on bypass” version
The level transmitter is mounted on the outside of the bypass tube with suitable mounting
material (non-magnetic) (see following figure).
To ensure a reliable measurement, the guide tube must be mounted free of
tension, without external deformations.
▶
The distance between guide tube and bypass tube must be as slow as possible.
▶
Only floats approved by us can be used.

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Operating instructions magnetostrictive level transmitter, models FLM-xAI, BLM-TAI (Ex)18
5. Commissioning, operation
Mounting with bypass
Guide tube length
Measuring range
min. magnet
position
min. magnet
position
Bypass float
Guide tube,
mounted free
of tension (not
deformed)
Bypass tube
Magnet position
Probe fixing
(un-magnetic)
Spacer
Section A-A
BLM for bypass
Distance from guide tube to centre of float:
max. distance depending on bypass float

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Operating instructions magnetostrictive level transmitter, models FLM-xAI, BLM-TAI (Ex) 19
5.2 Electrical connection
5.2.1 Connection diagram (Ex)
Prior to starting operation, please check all instruments for proper connection and
installation. Check the electrical supply, also of the connected instruments.
Voltage source Umax = DC 30 V
Minimum supply voltage Umin = 8 V
Overall resistance (incl. wiring resistance and load) ΣR = (U - Umin) / 0.0215 A
In hazardous areas, the intrinsically safe version of the level transmitter may only be
connected to buffer amplifiers that are certified by a notified body and whose electrical
output data meet the following criteria:
U0 ≤ 30 V
I0 ≤ 100 mA / 200 mA 1)
P0 ≤ 1 W
▶
For further data, see the EC-type examination certificate at www.wika.com.
1) The permissible input current li depends on the ambient temperature Ta.
Make sure that the permissible external capacitance C0and inductance L0of the buffer
amplifier are not exceeded if the level transmitter is used in a hazardous environment (see
chapter 6 “Safety-related characteristic values”).
The connection cable to the buffer amplifier must be marked in case of applications in a
hazardous environment - preferably as a blue cable for intrinsically safe circuits.
▶
Connection of the cable, see chapter 5.2.3 “Wiring with cable gland” and 5.2.4 “Wiring
with M12 connector”)
According to the dielectric strength requirements of EN 60079-11, section 6.3.13, there is
compliance with the insulation test between the intrinsically safe circuit and the chassis of
the level transmitter with a voltage of AC 500 V.
Wiring resistance
Supply voltage
Buffer amplifier (example)
5. Commissioning, operation

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Operating instructions magnetostrictive level transmitter, models FLM-xAI, BLM-TAI (Ex)20
5.2.2 Cable length
The maximum cable length is dependent upon the overall resistance, which is composed
of the wiring resistance and the load of connected instruments (see chapter 5.2.1
“Connection diagram (Ex)”).
The cable (length and cross-section) must be selected such that, in the event of the
highest current supply (21.5 mA), the voltage does not drop below the probe-specific
minimum supply voltage (8 V).
Make sure that, when used in hazardous areas, the permissible external capacitance C0
and inductance L0of the associated equipment are not exceeded (see chapter 6 “Safety-
related characteristic values”).
Maximum overall resistance with different supply voltages and also cable resistances at
different cross-sections:
Supply
voltage in V
Max. overall
resistance in Ω
Cable cross-
section in mm²
Cable resistance per m
of copper cable in Ω/m
12 (-5 %) 158 0.5 0.0356
1.0 0.0178
1.5 0.0119
24 (-5 %) 688 0.5 0.0356
1.0 0.0178
1.5 0.0119
The maximum cable length is calculated as follows:
L = Cable length in m
U = Supply voltage V (with negative tolerance value -5 %)
Umin = Minimum supply voltage V = 8 V
Imax = highest current supply A = 0.0215 A
RB= Load
RQ = Cable resistance of copper cable (per m) in Ω/m with cable cross-section Q in mm²
5. Commissioning, operation