KROHNE DK32 Series Wiring diagram

Variable area flowmeter with electrical built-ins
Equipment category II 2 G / II 2 D, EPL Gb / Db
in type of protection Flameproof enclosure Ex d and
in type of protection Equipment dust-ignition protection through enclosure Ex t
DK32 - DK34
DK32 - DK34DK32 - DK34
DK32 - DK34 Supplementary Instructions
Supplementary InstructionsSupplementary Instructions
Supplementary Instructions
© KROHNE 06/2019 - 4007137501 - AD DK32-34 Exd Gb-Db R01 en

CONTENTS
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DK32 - DK34
1 Safety instructions 3
1.1 General notes ................................................................................................................... 3
1.2 EU conformity ................................................................................................................... 3
1.3 Approval according to the IECEx scheme ........................................................................ 3
1.4 Safety instructions............................................................................................................ 4
2 Device description 5
2.1 Device description ............................................................................................................ 5
2.2 Description code............................................................................................................... 5
2.3 Marking............................................................................................................................. 6
2.4 Flammable products ........................................................................................................ 7
2.5 Equipment category .........................................................................................................7
2.6 Types of protection ........................................................................................................... 8
2.6.1 Protection type - Flameproof enclosure ................................................................................ 8
2.6.2 Protection type - Protection through enclosure .................................................................... 8
2.7 Ambient temperature / temperature classes.................................................................. 9
2.8 Surface temperature for equipment category II 2 D...................................................... 10
2.9 Electrical data................................................................................................................. 10
3 Installation 11
3.1 Mounting ......................................................................................................................... 11
3.2 Special conditions........................................................................................................... 12
4 Electrical connections 13
4.1 General notes ................................................................................................................. 13
4.2 Grounding and equipotential bonding............................................................................ 15
5 Operation 16
5.1 Start-up........................................................................................................................... 16
5.2 Operation ........................................................................................................................ 16
5.3 Electrostatic charge .......................................................................................................16
6 Service 17
6.1 Maintenance ................................................................................................................... 17
6.2 Dismantling .................................................................................................................... 18
7 Notes 19

SAFETY INSTRUCTIONS 1
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1.1 General notes
This additional instruction applies to explosion-protected versions of variable area flowmeters
with electrical built-ins and the marking II 2 G and II 2 D or EPL Gb and Db.
It completes the standard manual for the non explosion-protected versions.
The information given in this instruction contains only the data relevant to explosion protection
of category 2.
The technical details given in the manual for the non explosion-protected versions remain
unchanged unless they will be excluded or replaced by this supplementary instruction.
1.2 EU conformity
The manufacturer declares with the EU declaration of conformity on his own responsibility
conformity with the protection goals of directive 2014/34/EU for use in hazardous areas.
Conformity with harmonised standards was checked in accordance with EN 60079-0:2012,
EN 60079-1:2014 and EN 60079-31:2014.
The EU declaration of conformity is based on the EU type examination certificate of the KIWA
ExVision:
If necessary, the EU type examination certificate can be downloaded from the manufacturer's
website.
1.3 Approval according to the IECEx scheme
Conformity with IECEx standards was tested in accordance with the "IECEx Certification Scheme
for Explosive Atmospheres" according to IEC 60079-0:2011, IEC 60079-1:2014 and
IEC 60079-31:2013.
The number of the IEC certificate is:
KIWA 18ATEX0008 X
KIWA 18ATEX0008 XKIWA 18ATEX0008 X
KIWA 18ATEX0008 X
IECEx KIWA 18.0007X
IECEx KIWA 18.0007XIECEx KIWA 18.0007X
IECEx KIWA 18.0007X

1 SAFETY INSTRUCTIONS
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1.4 Safety instructions
If these instructions are not followed, there is a risk of explosion.
Assembly, installation, start-up and maintenance may only be performed by personnel trained in
explosion protection!
CAUTION!
The operator or his agent is responsible for observing any additional standards, directives or
laws if required due to operating conditions or place of installation.
This applies in particular to the use of easily detachable process connections when measuring
flammable media.
CAUTION!
When an equipment fault is detected the device shall be de-energised and send back to the
manufacturer for repair.

DEVICE DESCRIPTION 2
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2.1 Device description
Variable area flowmeters measure and display the flow of flammable and non-flammable gases
and liquids.
The indication unit is equipped with HART
®
communication.
2.2 Description code
The safety description code consists of the following elements *:
* positions which are not needed are omitted (no blank positions)
Figure 2-1: Safety description code
1 32 - with valve and horizontal connection / 34 - without valve and vertical connection
2 RE - inlet pressure regulator / RA - outlet pressure regulator
3 ESK - version with current output
4 Marking without influence on the explosion safety protection
5 Ex - explosion-protected equipment

2 DEVICE DESCRIPTION
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2.3 Marking
The marking of the entire device is on the indication unit, where the following identification plate
can be found. An additional marking with the production number (P/A) is located inside of the
indication.
Figure 2-2: Example of a nameplate
1 Device type
2 Manufacturer
3 Notified body ATEX
4 Rating data: temperature & pressure rating
5 Ex data according to KIWA 18ATEX0008 X or IECEx KIWA 18.0007X
6 Built-in equipment
7 Note to observe the documentation and for disposal
8 PED data

DEVICE DESCRIPTION 2
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2.4 Flammable products
Atmospheric conditions:
Atmospheric conditions:Atmospheric conditions:
Atmospheric conditions:
The standard atmospheric conditions under which it may be assumed that Ex equipment can be
operated are:
•Temperature: -20...+60°C / -4...+140°F
•Pressure: 80...110 kPa (0.8...1.1 bar) / 11.6...15.9 psi
•Air with normal oxygen content, typically 21%v/v
Ex equipment operating outside the standard temperature range must be tested and certified
(e.g. for ambient temperature range -40...+65°C / -40...+149°F).
Ex equipment operating outside the standard atmospheric pressure range and standard oxygen
content is not permitted.
Operating conditions:
Operating conditions:Operating conditions:
Operating conditions:
The measuring unit of variable area flowmeters operate outside the standard atmospheric
pressure range, which means that explosion protection, regardless of the zone assignment, is
fundamentally not applicable for the measuring unit (piping).
2.5 Equipment category
Variable area flowmeters are designed in category II 2 G / II 2 D or EPL Gb and EPL Db according
to EN 60079-0, EN 60079-1 and EN 60079-31 for use in zone 1 or zone 21.
The inside of the measuring unit is also approved for zone 1.
CAUTION!
Operation with flammable products is only permitted as long as no explosive fuel/air mixture
builds up inside of the piping at the same time the atmospheric conditions are exceeded.
The operator is responsible to ensure that the flowmeter is operated safely in terms of the
temperature and pressure of the products used. In case of operation with flammable products
the measuring units must be included in the periodic pressure tests of the piping.
INFORMATION!
Definition of zone 1:
An area in which an explosive atmosphere, as a result of the mixture of flammable substances in
the form of gas, steam or mist with air, under normal operation may occasionally occur.
Definition of zone 21:
An area in which an explosive atmosphere may occasionally occur in the form of a cloud of
flammable dust in the air under normal operation.

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2.6 Types of protection
The variable area flowmeter is available in different protection types, depending on the selected
indicator version. The markings are listed and explained in the following sub-sections.
2.6.1 Protection type - Flameproof enclosure
The variable area flowmeter is designed with protection type "flameproof enclosure" according
to EN 60079-1. The explosion protection is ensured through design measures of the housing.
The marking is:
II 2G Ex db IIC T6...T1 Gb
II 2G Ex db IIC T6...T1 GbII 2G Ex db IIC T6...T1 Gb
II 2G Ex db IIC T6...T1 Gb
The marking contains the following information:
2.6.2 Protection type - Protection through enclosure
The variable area flowmeter is designed with protection type "protection trough enclosure"
according to EN 60079-31. Dust protection is guaranteed by the use of a housing which provides
appropriate protection against penetration of dust.
The marking is:
II 2D Ex tb IIIC T85
II 2D Ex tb IIIC T85II 2D Ex tb IIIC T85
II 2D Ex tb IIIC T85°C...T140
C...T140C...T140
C...T140°C Db
C DbC Db
C Db
IP65
IP65IP65
IP65
The marking contains the following information:
II
IIII
II Explosion protection, group II
2
22
2Equipment category 2
G
GG
GGas explosion protection
Ex d
Ex dEx d
Ex d Protection type "Flameproof enclosure"
IIC
IICIIC
IIC Gas group, suitable for gas groups IIA, IIB, IIC
T6...T1
T6...T1T6...T1
T6...T1 Temperature class, suitable for T6...T1
Gb
GbGb
Gb EPL, suitable for zone 1
Table 2-1: Description of the marking
II
IIII
II Explosion protection, group II
2
22
2Equipment category 2
D
DD
DDust ignition protection
Ex t
Ex tEx t
Ex t Protection type "Equipment - dust ignition protection through enclosure"
IIIC
IIICIIIC
IIIC Dust group, suitable for dust groups IIIA, IIIB and IIIC
T85
T85T85
T85°C...T140
C...T140C...T140
C...T140°C
CC
CMaximum surface temperature at +65°C / +149°F ambient temperature
Db
DbDb
Db EPL, suitable for zone 21
IP65
IP65IP65
IP65 Foreign bodies and water protection
Table 2-2: Description of the marking

DEVICE DESCRIPTION 2
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2.7 Ambient temperature / temperature classes
Due to the influence of the product temperature, no fixed temperature class is assigned to
variable area flowmeters. The temperature class of these devices is rather a function of the
present product temperature and ambient temperature.
The classification is outlined in the following tables.
The tables take into account the following parameters:
•Ambient temperature T
amb
•Product temperature T
m
INFORMATION!
The lowest ambient temperature is -40
° C/-40 ° F.
INFORMATION!
The maximum permissible product temperatures listed in the tables are valid under
the following conditions:
• The measuring device is installed and operated in accordance with the installation
instructions in the standard manual.
• It must be ensured that the flowmeter is not heated by the effects of additional heat radiation
(sunshine, neighbouring system components) and thus operated above the permissible
ambient temperature range.
• Insulation must be limited to the piping.
Unobstructed ventilation of the indicator part must be ensured.
Maximum permissible product temperature T
m
[°C]
T6
T6T6
T6 T5
T5T5
T5 T4
T4T4
T4 T3...T1
T3...T1T3...T1
T3...T1
Ambient
temperature 40 50 55 50 65 70 40 60 65 70 40 60 65 70
DK3./../ESK/. 85 85 85 100 100
190 1135 1105 1100 190 1140 1105 1100 190 1
Table 2-3: DK3./../ESK/./..-Ex permissible product and ambient temperatures in °C
1Heat-resistant cable and cable entry ≥90°C
Maximum permissible product temperature T
m
[°F]
T6
T6T6
T6 T5
T5T5
T5 T4
T4T4
T4 T3...T1
T3...T1T3...T1
T3...T1
Ambient
temperature 104 122 131 122 149 158 104 140 149 158 104 140 149 158
DK3./../ESK/. 185 185 185 212 212
1194 1275 1221 1212 1194 1284 1221 1212 1194 1
Table 2-4: DK3./../ESK/./..-Ex permissible product and ambient temperatures in °F
1Heat-resistant cable and cable entry ≥194°F

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2.8 Surface temperature for equipment category II 2 D
For use in areas with combustible dust it should be noted that the indicated maximum surface
temperature of T85°C at an ambient temperature of +65°C / +149°F and a product temperature
of +75°C / +167°F is valid without a dust layer.
For higher product temperatures the maximum surface temperature is defined by the product.
At temperatures above +90°C / +194°F, heat-resistant cables and cable entries ≥+90°C / +194°F
must be used.
2.9 Electrical data
The following maximum values apply for connecting the electrical signal circuits:
U
N
12...32 VDC
I
N
4...20 mA
Table 2-5: Version DK3./../ESK/./..-Ex

INSTALLATION 3
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3.1 Mounting
Mounting and setup must be carried out according to the applicable installation standards
(e.g. EN 60079-14) by qualified personnel trained in explosion protection.
The information given in the manual and the supplementary instructions must always be
observed.
Variable area flowmeters must be installed in such a way that
•no external forces are affecting the indication unit.
•the device is accessible for any necessary visual inspections and can be viewed from all sides.
•the nameplate is clearly visible.
•it can be operated from a location with secure footing.
CAUTION!
The manufacturer is not liable for any damage resulting from improper use or use other than the
intended purpose. This applies in particular to hazards due to insufficient corrosion resistance
and suitability of the materials in contact with product.
DANGER!
Components made of titanium in oxygen applications
Components made of titanium in oxygen applicationsComponents made of titanium in oxygen applications
Components made of titanium in oxygen applications
Variable area flowmeters with titanium components are NOT
NOTNOT
NOT suitable for use in explosion-
protected areas in conjunction with oxygen applications (products with an oxygen content which
is significantly above the oxygen content in the earth's atmosphere)!

3 INSTALLATION
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3.2 Special conditions
Equipotential bonding
Variable area flowmeters must be included in the equipotential bonding of the hazardous area.
Electronics compartment lock
Lock the dustproof and/or flameproof electronics compartment of the variable area flowmeter
during operation. First tighten the cover by hand. Then tighten the cover again by about 90°.
The cover for the electronics compartment is secured by means of a lock.
Use a WS3 Allen key to turn the screw.
No waiting period is necessary prior to opening the electronics compartment.
Flameproof joints in the housing
The flameproof thread gap between the cover and the electronics compartment must be
inspected visually after opening. The housing must be replaced if there is any damage to the joint
area. The flameproof joints are not intended for repair.

ELECTRICAL CONNECTIONS 4
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4.1 General notes
Rated values for insulation
•The insulation of the variable area flowmeter is rated in compliance with IEC 60664-1.
The following rating parameters are taken into account:
•Overvoltage category for signal and instrument loops: II
•Pollution degree of the insulation: 2
Terminal compartment
The electrical connection for the power supply and I/O functions is made in the electronics
compartment of the signal converter. The protection type of the electronics compartment is "d"
and/or "t". If no cable gland was ordered, the connection thread is simply closed with a blind
plug. This must be replaced by a suitable cable gland in accordance with EN 60079-1 and/or
EN 60079-31. The cables can enter the electronics compartment in two different ways.
•Direct entry of the connecting cables by way of approved flameproof M16x1.5 cable glands
into the flameproof/dust proof terminal compartment (V ≤2000 cm³). The cable glands
require a separate test certificate in accordance with EN 60079-1/EN 60079-31.
Observe the requirements of the test certificate for the cable glands.
•Direct entry of the connecting cables by way of conduits into the flameproof enclosed
terminal compartment of the device. Once the conduit has been screwed in, it must form a
flameproof joint with the housing with a minimum thread length of 8 mm / 0.3". A suitable
mechanical stopping box must be provided in accordance with installation provisions.
The conduit must be installed in compliance with its separate test certificate.
Electrical connection
Figure 4-1: Electrical connection ESK
1 Connection terminals
2 Cable entry

4 ELECTRICAL CONNECTIONS
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Connecting cables
The connecting cables should be selected according to the applicable installation standards
(e.g. EN 60079-14 / VDE 0165) and the maximum operating temperature.
•The connecting cables must be fixed and laid so they are sufficiently protected against
damage.
•Lay cables so as to ensure that there is sufficient distance between surfaces of the
measuring unit and the connecting cable.
•Supplied cable entries guarantee protection against foreign objects and water (ingress
protection) IP66/68 according to EN 60529.
•The outer diameter of the connecting cable must be within the sealing range of the cable
entry (e.g. 7...12 mm / 0.27...0.47").
Ensure that the gaskets and incised gasket ring are tight.
CAUTION!
The IP protection category of the signal converter housing is largely determined by the cable
gland used and the installation.

ELECTRICAL CONNECTIONS 4
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4.2 Grounding and equipotential bonding
If the device is not sufficiently electrostatically grounded via the process pipes, an additional
ground connection must be established using the ground terminal 1
11
1. The position of the ground
terminal is illustrated below.
The connection only ensures an electrostatic connection of the device and does not comply with
the requirements of an equipotential bonding connection.
Figure 4-2: Ground terminal for ESK
INFORMATION!
The temperature at the electrostatic equalization connection of the DK32-DK34 measuring unit
corresponds to the process temperature. It is thus the responsibility of the operator to select the
connecting cable according to the process temperature.

5 OPERATION
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5.1 Start-up
Start-up is only permitted when the variable area flowmeter:
•is correctly installed in the system and connected.
•has been checked for the proper state with regard to its installation and connection
requirements.
The operator of the system has to check prior to start-up, if the start-up was in compliance with
the national regulations for checks.
5.2 Operation
Variable area flowmeters must be operated in such a way that they remain within the maximum
and minimum permissible temperatures and pressures and the electrical limit values.
Variable area flowmeters may only be operated if the equipment parts necessary for safety are
effective in the long run, and are not rendered inoperable during operation.
5.3 Electrostatic charge
In order to avoid ignition hazards due to electrostatic charge, variable area flowmeters
may not be used in areas with:
•processes that generate strong charges,
•mechanical friction and cutting processes,
•spraying of electrons (e.g. in the vicinity of electrostatic painting systems).
CAUTION!
Ignition risks caused by pressure surges, impact or friction must particularly be avoided when
titanium measuring units or floats are used.
WARNING!
Electrostatic charging of the housing surface by friction must be avoided.
Variable area flowmeters must not be dry cleaned.

SERVICE 6
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6.1 Maintenance
Maintenance work of a safety-relevant nature within the meaning of explosion protection may
only be carried out by the manufacturer, his authorised representative or under the supervision
of authorised inspectors.
For systems in hazardous areas, regular tests are required in order to maintain the proper
condition.
The following checks are recommended:
•Check the housing, the cable entries and the feed lines for corrosion and/or damage.
•Check the measuring unit and the piping connections for leakage.
•Check the measuring unit and the indicator for dust deposits.
•Include the flowmeter in the regular pressure test of the process line.
During re-assembly after maintenance of the indicator/converter (or replacement) or
the flowmeter, the operator must take appropriate measures to ensure that
•no charge is applied to the surface of the housing.
•no charge is applied to the inner surfaces of the housing.
•any damaged gaskets are replaced.
The cover is to be closed following maintenance work on the indicator.
Cleaning the measuring unit
Depending on the application, worst-case operating conditions may lead to reduced measuring
performance as a result of fouling of the measuring system. Clean the measuring unit in
accordance with the standard manual for non-explosion protected versions.
The measuring unit must be dismantled for cleaning. This dismantling will need to be
coordinated with operating conditions (e.g., check for existence of a flammable liquid or
explosive atmosphere in or at the tank or pressurized tank) and is within the responsibility of the
operator.
To do this, follow the instructions for exchanging the entire device (for details refer to
Dismantling on page 18).
CAUTION!
When opening the indicator or terminal compartment, the operator must ensure there is a
controlled environment that prevents dirt or similar from penetrating into the device. Following
connection or maintenance, the operator must ensure that the inside of the device is cleaned
with suitable agents.

6 SERVICE
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6.2 Dismantling
General notes
General notesGeneral notes
General notes
The dismantling and installation is within the responsibility of the operator.
Only identical signal converter from the manufacturer may be used.
Exchanging the signal converter
Exchanging the signal converterExchanging the signal converter
Exchanging the signal converter
Due to the design of the variable area flowmeters, from a safety perspective the signal converter
can be replaced with an identical signal converter.
The measuring unit does not need to be removed from the process connections.
This also applies to pressurised processes.
The device must be de-energised, if it is absolutely necessary to open the flameproof enclosure
or the dustproof electronics compartment in the presence of a potentially explosive atmosphere.
Before connecting or disconnecting the electrical connection cables of the device, make sure
that all cables leading to the display are isolated from the ground of the hazardous area. This
also applies to protective earth (PE) or functional earth (FE) and equipotential bonding
conductors (PA).
After opening the signal converter, treat the ignition-proof cover threads as necessary with
UNIMOLY C220
®
lubricating paint.
After opening the signal converter, grease the cover seals if necessary to avoid dry running.
Use for example the multi-purpose grease NONTRIBOS
®
, type Li EP2.
Close the housing cover immediately after the spare parts are exchanged. Ensure that the cover
seal is tight.
Exchanging the entire device
Exchanging the entire deviceExchanging the entire device
Exchanging the entire device
The same requirements as described in "Exchanging the signal converter" apply for "Exchanging
the entire device".
CAUTION!
There may be a loss of measuring accuracy!
CAUTION!
Pressurised process connections have to be depressurised before removing the process
connection.
Where environmentally critical products are concerned, carefully decontaminate the wetted
parts of the device after dismantling.
The dismantling and installation is within the responsibility of the operator.

NOTES 7
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• Flow
• Level
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Head Office KROHNE Messtechnik GmbH
Ludwig-Krohne-Str. 5
47058 Duisburg (Germany)
Tel.: [phone]
Fax: [phone]
[email protected]
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