KROHNE OPTIFLUX 4040 C Series Wiring diagram

Ex addendum
OPTIFLUX 4040 C
OPTIFLUX 4040 COPTIFLUX 4040 C
OPTIFLUX 4040 C Supplementary instructions
Supplementary instructionsSupplementary instructions
Supplementary instructions
© KROHNE 09/2010 - 7312232100 - AD EX OPTIFLUX 4040 C R01 en

CONTENTS
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OPTIFLUX 4040 C
1 Introduction 3
1.1 Safety instructions from the manufacturer ..................................................................... 3
1.1.1 Disclaimer ............................................................................................................................... 3
1.1.2 Product liability and warranty ................................................................................................ 4
1.1.3 Information concerning the documentation........................................................................... 4
1.1.4 Warnings and symbols used................................................................................................... 5
1.1.5 Manufacturer .......................................................................................................................... 5
1.2 Safety instructions for the operator................................................................................. 6
1.3 Approval............................................................................................................................ 6
1.4 General description .......................................................................................................... 6
1.4.1 Flow sensor............................................................................................................................. 7
1.4.2 Signal converter...................................................................................................................... 7
1.5 Nameplates ...................................................................................................................... 8
2 Temperature limits 9
2.1 Temperatures................................................................................................................... 9
3 Electrical connections 10
3.1 Equipotential bonding system........................................................................................ 10
3.2 Terminal arrangment..................................................................................................... 10
3.3 Description of the output circuits................................................................................... 11
3.4 Safety-technical data......................................................................................................12
3.5 Connection examples ..................................................................................................... 13
3.5.1 Example of OPTIFLUX 4040 C-EEx in 2-wire mode.............................................................. 13
3.5.2 Example of OPTIFLUX 4040 C-EEx in 2x2-wire mode (4-wire) ............................................ 14
4 Operation 16
5 Maintenance and service 17
5.1 Maintenance ................................................................................................................... 17
5.2 Replacement of electronics unit .................................................................................... 17
6 Notes 19

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1.1 Safety instructions from the manufacturer
1.1.1 Disclaimer
The manufacturer will not be liable for any damage of any kind by using its product, including,
but not limited to direct, indirect or incidental and consequential damages.
This disclaimer does not apply in case the manufacturer has acted on purpose or with gross
negligence. In the event any applicable law does not allow such limitations on implied warranties
or the exclusion of limitation of certain damages, you may, if such law applies to you, not be
subject to some or all of the above disclaimer, exclusions or limitations.
Any product purchased from the manufacturer is warranted in accordance with the relevant
product documentation and our Terms and Conditions of Sale.
The manufacturer reserves the right to alter the content of its documents, including this
disclaimer in any way, at any time, for any reason, without prior notification, and will not be liable
in any way for possible consequences of such changes.

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1.1.2 Product liability and warranty
The operator shall bear responsibility for the suitability of the device for the specific purpose.
The manufacturer accepts no liability for the consequences of misuse by the operator. Improper
installation and operation of the devices (systems) will cause the warranty to be void. The
respective "Standard Terms and Conditions" which form the basis for the sales contract shall
also apply.
1.1.3 Information concerning the documentation
To prevent any injury to the user or damage to the device it is essential that you read the
information in this document and observe applicable national standards, safety requirements
and accident prevention regulations.
If this document is not in your native language and if you have any problems understanding the
text, we advise you to contact your local office for assistance. The manufacturer can not accept
responsibility for any damage or injury caused by misunderstanding of the information in this
document.
This document is provided to help you establish operating conditions, which will permit safe and
efficient use of this device. Special considerations and precautions are also described in the
document, which appear in the form of underneath icons.

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1.1.4 Warnings and symbols used
Safety warnings are indicated by the following symbols.
• HANDLING
HANDLINGHANDLING
HANDLING
This symbol designates all instructions for actions to be carried out by the operator in the
specified sequence.
iRESULT
RESULTRESULT
RESULT
This symbol refers to all important consequences of the previous actions.
1.1.5 Manufacturer
The instrument is developed and manufactured by:
KROHNE Altometer
Kerkeplaat 12
3313 LC Dordrecht
The Netherlands
DANGER!
This information refers to the immediate danger when working with electricity.
DANGER!
This warning refers to the immediate danger of burns caused by heat or hot surfaces.
DANGER!
This warning refers to the immediate danger when using this device in a hazardous atmosphere.
DANGER!
These warnings must be observed without fail. Even partial disregard of this warning can lead to
serious health problems and even death. There is also the risk of seriously damaging the device
or parts of the operator's plant.
WARNING!
Disregarding this safety warning, even if only in part, poses the risk of serious health problems.
There is also the risk of damaging the device or parts of the operator's plant.
CAUTION!
Disregarding these instructions can result in damage to the device or to parts of the operator's
plant.
INFORMATION!
These instructions contain important information for the handling of the device.
LEGAL NOTICE!
This note contains information on statutory directives and standards.

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For information, maintenance or service please contact your nearest local KROHNE
representive.
1.2 Safety instructions for the operator
These additional instructions are an extension to the handbook. All technical information as
described in the handbook is applicable, when not specifically excluded, completed or replaced
by the instructions in these additional instructions.
1.3 Approval
The OPTIFLUX 4040 C-EEx electromagnetic compact flowmeter in 2-wire technology is in
accordance with European Directive 94/9/EC (ATEX 100a) and approved for hazardous classified
areas of Zone 1 and 2 under:
KEMA 01 ATEX 2200 X
KEMA 01 ATEX 2200 XKEMA 01 ATEX 2200 X
KEMA 01 ATEX 2200 X
1.4 General description
The OPTIFLUX 4040 C-EEx flowmeter consists of the IFC 040 signal converter unit, which is
screwed on top of the flow sensor. The flowmeter is marked with one of the codes below:
EEx marking:
WARNING!
• Do not change the device. Unauthorized changes affect the explosion safety of the devices.
• The prescriptions and regulations as well as the electrical data described in the EC type
examination certificate must be obeyed.
• Beside the instructions for electrical installations in non-hazardous locations according to
the applicable national standard (equivalent to HD 384 or IEC 60364, e.g. VDE 0100),
especially the regulations in EN 60079-14 "Electrical installations in hazardous locations",
equivalent national standard (e.g. DIN VDE 0165 Part 1) or dust hazardous areas such as
EN 61241-14 must be complied with!
• Installation, establishment, utilization and maintenance are only allowed to be executed by
personnel with an education in explosion safety!
INFORMATION!
All type examination certificates can be downloaded from the website.
Nominal
NominalNominal
Nominal
diameter
diameterdiameter
diameter
EEx e and d connection compartment,
EEx e and d connection compartment,EEx e and d connection compartment,
EEx e and d connection compartment,
II 2 GD
10...20 EEx dme [ib] IIC T6...T3
25...150 EEx de [ib] IIC T6...T3

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1.4.1 Flow sensor
The flow sensor contains two field coils and two electrodes.
Protection category
1.4.2 Signal converter
The IFC 040 signal converter consists of a cylindrical housing of die-casted aluminum, which has
two separate compartments, divided from each other by an integrated wall with casted
flameproof terminal feed-through. The neck at the bottom of the housing contains a flameproof
cable feed-through. The signal converter housing is on both ends closed by a cylindrical
threaded cover with O-ring sealing. The housing has an ingress protection degree of at least
IP 67 conform to EN 60529.
Electronics compartment
Electronics compartmentElectronics compartment
Electronics compartment
The electronics compartment accomodates the pre-certified IFC 040 electronics unit with
approval number PTB 00 ATEX 2213 U. The compartment is designed with type of protection
flameproof enclosure "d" according to EN 50018. It is closed by a flameproof display cover with
glass window.
Terminal compartment
Terminal compartmentTerminal compartment
Terminal compartment
The terminal compartment has seven terminals for all connections. There are two versions
possible with a different explosion protection according to the European Standards, which is
dependent on the safety-technical maximum voltage Um of the mains power supply system to
which the flowmeter is connected.
Version A: terminal compartment "EEx de [ib]" with U
Version A: terminal compartment "EEx de [ib]" with UVersion A: terminal compartment "EEx de [ib]" with U
Version A: terminal compartment "EEx de [ib]" with Um
mm
m= 60 V
The connections of the output circuits can be configured by the customer in one of the folllowing
types of explosion protection:
•EEx [ib]: intrinsic safety, category "ib"
•EEx e: increased safety
•EEx d: flameproof enclosure (note warning below)
Nominal
NominalNominal
Nominal
diameter
diameterdiameter
diameter
Type of protection
Type of protectionType of protection
Type of protection
10...20 Housing: Encapsulation "m" according to EN 50028 and increased safety "e"
according to EN 50019
Electrodes: Intrinsic safety "ib" according to EN 50020
25...150 Housing: Flameproof enclosure "d" according to EN 50018
Electrodes: Intrinsic safety "ib" according to EN 50020
INFORMATION!
The intrinsically safe electrode circuits are only internal circuits and not accessible for the
customer.

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Version B: terminal compartment "EEx de" with U
Version B: terminal compartment "EEx de" with UVersion B: terminal compartment "EEx de" with U
Version B: terminal compartment "EEx de" with Um
mm
m= 250 V
The connections of the output circuits can be configured by the customer in one of the folllowing
types of explosion protection:
•EEx e: increased safety
•EEx d: flameproof enclosure (note warning below)
Cable or conduit entries
Cable or conduit entriesCable or conduit entries
Cable or conduit entries
1.5 Nameplates
WARNING!
The used cable entries (glands and/or blind plugs) must be ATEX certified. The OPTIFLUX 4040
C-EEx is delivered with an EEx e cable gland and EEx e blind stop. The cable gland and blind stop
are suitable for connections in EEx e and EEx ib, but not for EEx d.
When connection is planned in EEx d, special EEx d certified conduits, glands or blind stops must
be used. ATEX approved EEx d cable glands, screw threaded adapters as well as blind plugs are
no integral part of the delivery and must be purchased by the customer or can be ordered as
special part. Note that for a correct choice of the EEx d cable gland the precise cable type and
cable dimensions (e.g. outside diameter) must be given.
Figure 1-1: Example of a nameplate
1 Name and address of the manufacturer.
2 CE sign with number (s) of notified body / bodies.
3 Specific sign for explosions, protection, Ex codes and number of EC type exmination certificate.
4 Explosion safety notes.
5 Data for EEx ib connection.
6 Data for EEx e or EEx d connection.

TEMPERATURE LIMITS 2
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2.1 Temperatures
The OPTIFLUX 4040 C-EEx compact flowmeter is designed for ambient temperatures in the
range of -40...+60°C.
The allowed process liquid temperature is among others limited by the combustible atmosphere
that (possibly) surrounds the apparatus, which again is determined by the temperature class of
the atmosphere.
Temperature classification DN10...20
Temperature classification DN10...20Temperature classification DN10...20
Temperature classification DN10...20
Temperature classification DN25...150
Temperature classification DN25...150Temperature classification DN25...150
Temperature classification DN25...150
Temperature
(for gasses)
Max. surface
temperature
(for dusts)
Maximum process liquid temperature
Ta≤40°C Ta≤50°C Ta≤60°C
T6 T85°C75°C70°C70°C
T5 T100°C95°C90°C75°C
T4 T135°C130°C115°C75°C
T3 T180°C150°C115°C75°C
Temperature
(for gasses)
Max. surface
temperature
(for dusts)
Maximum process liquid temperature
Ta≤40°C Ta≤50°C Ta≤60°C
T6 T85°C70°C70°C70°C
T5 T100°C85°C85°C85°C
T4 T135°C120°C120°C115°C
T3 T180°C180°C180°C115°C
Use heat-resistant cables No No Yes

3ELECTRICAL CONNECTIONS
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3.1 Equipotential bonding system
The flowmeter must be incorporated into the equipotential bonding system through the internal
or external PE-clamp. The external clamp is suitable for wires up to 4 mm2cross section.
Disconnection from the equipotential bonding system is only allowed when the flowmeter is not
in contact with power supplies or ground voltages outside the hazardous area.
3.2 Terminal arrangment
To connect external devices to the signal output terminals, the wiring requirements for the type
of protection of the compartment must also be conform to the international or national standard
involved (e.g. EN 60079-14). The terminal arrangment is shown by the following figure.
The following outputs are available for connection to external circuits:
Current output
Current outputCurrent output
Current output
This circuit constitutes a passive 4...20 mA current loop and includes the HART protocol of the
communication device (choice of polarity free).
Additional power supply or power booster
Additional power supply or power boosterAdditional power supply or power booster
Additional power supply or power booster
These terminals are connected to provide the 2x2 wire mode (choice of polarity free).
Binary outputs
Binary outputsBinary outputs
Binary outputs
Terminals B1 and Bgnd can be configured as pulse or status output through software.
Terminals B2 and Bgnd can be configured as pulse or status output to NAMUR.
Galvanical separation of circuits
Galvanical separation of circuitsGalvanical separation of circuits
Galvanical separation of circuits
The internal electrode circuit with type of protection "EEx ib" is galvanically connected to the
aluminum signal converter housing (i.e. PE potential). The current output, the additional power
supply and the internal field current circuit are galvanically connected to each other.
Figure 3-1: Terminals OPTIFLUX 4040 C
1 Current output
2 Binary outputs
3 Power booster (additional power supply)
4 PE (Protective Earth) / FE (Functional Earth)

ELECTRICAL CONNECTIONS 3
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3.3 Description of the output circuits
The terminal compartment of the OPTIFLUX 4040 C-EEx is, with respect to the explosion
protection, available in two versions. The version can be identified by the information that is
listed on the data plate, which is mounted on the signal converter housing.
Version A: terminal compartment "EEx de [ib]" with U
Version A: terminal compartment "EEx de [ib]" with UVersion A: terminal compartment "EEx de [ib]" with U
Version A: terminal compartment "EEx de [ib]" with Um
mm
m= 60 V
The customer can decide in which type of explosion protection the output circuits - current
output, additional power supply and binary outputs (i.e. pulse and/or status outputs) - can be
driven: in type of protection "EEx ib", "EEx e" or "EEx d".
If type of protection EEx e or EEx d is used, the markings for "Intrinsically safe" - that are blue
o-ring around the cable gland and the blue sticker in the connection compartment - should be
removed.
The safety-technical maximum voltage Um(maximum effective AC or DC voltage) of the mains
power supply system for the terminal compartment in type of protection EEx de [ib] is restricted
to 60 V. With this maximum voltage it is guaranteed that the protective components on which the
intrinsic safety of these circuits depends are not overloaded. This condition is met if the mains
power supply system satisfies the PELV requirements in accordance with IEC 364 / IEC 536.
Version B: terminal compartment "EEx de" with U
Version B: terminal compartment "EEx de" with UVersion B: terminal compartment "EEx de" with U
Version B: terminal compartment "EEx de" with Um
mm
m= 250 V
This version is intended for applications where the mains power supply system provides a
maximum safety-technical voltage of Um= 250 V. The terminals can either be provided with type
of protection increased safety "EEx e" according to EN 50019 or flameproof enclosure "EEx d"
conform to EN 50018. Type of protection intrinsical safety "EEx ib" is not allowed for this version.
Important notes (applicable for versions A and B)
•The intrinsically safe "EEx ib" internal electrode circuit is supplied by the IFC 040-EEx signal
converter electronics unit inside the electronics compartment. This circuit is separated from
all other circuits up to a maximum voltage of Um= 250 V according to EN 50020. The internal
electrode circuit with type of protection intrinsic safety "ib" is galvanically connected with the
PE (housing potential).
•The current output (terminals I, Ignd) and the additional power supply (terminals 1L=, 0L=)
must be galvanically separated from each other. To avoid voltage or current summation, at
least one of the two circuits must be isolated from earth potential. It is not allowed to drive
both circuits at the same time with grounded zener barriers. Both current circuits, including
all connection cables, must be galvanically separated at all times according to the valid
regulations.
•Also in case of non-intrinsically safe connections, it is absolutely necessary to maintain a
galvanic separation between the current output circuits and the additional power supply
connections.
WARNING!
It is not allowed to mix two different types of protection (e.g. current output in type of protection
"EEx ib" and pulse/status outputs in "EEx e" or "EEx d").
INFORMATION!
It is allowed to change the type of protection of the terminal compartment afterwards, if it is
garuanteed that the maximum voltage U
m
of the mains power supply system is always
limited at 60 V!

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•A safe connection of the IFC 040-EEx signal converter electronics with the equipotential
bonding system is achieved through the zinc-plated mounting frame, which must be securely
screwed to the aluminum signal converter housing (PE potential) by means of two long-
shafted screws. To access the two long-shafted screws it is necessary to unscrew the display
unit and fold it aside. The screws must be tightly secured with a torque of 1.3 Nm (a 2 Pt.
Phillips screwdriver is recommended).
3.4 Safety-technical data
Safety-technical data of output circuits
CAUTION!
The functional-technical data must also be regarded, please see the standard documentation.
Terminal
designation
Function Electrical data (per circuit)
Type of protection
"EEx ib"
Type of protection
"EEx e"
Circuit 1
I, Ignd
Current output, passive
(2-wire connection)
4...20 mA, HART®is
possible.
Maximum values:
Ui= 30 V, Ii= 100 mA,
Pi= 1.0 W
Ci= 20 nF, Li= 0, Um= 60 V
Un= 14...36 VDC
In= 4...20 mA
Um= 250 V
Circuit 2
1L=, 0L= Additional power supply or power booster
(4-wire connection).
Additional to Circuit 1
(option).
Un= 14...36 VDC
In= 22 mA
Um= 250 V
Circuit 3
B1, Bgnd
B2, Bgnd
Passive pulse/status
output 1 / 2 Maximum values: Ui= 30 V, Ii= 100 mA,
Pi= 1.0 W
Ci= 0, Li= 0, Um= 60 V
Maximum values:
U = 36 VDC
I = 100 mA
Um= 250 V

ELECTRICAL CONNECTIONS 3
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3.5 Connection examples
In the following sections examples for connection of the OPTIFLUX 4040 C-EEx compact
flowmeter are described for operation in the 2-wire mode as well as in the 2x2-wire mode.
3.5.1 Example of OPTIFLUX 4040 C-EEx in 2-wire mode
The diagram shows an OPTIFLUX 4040 C-EEx with the terminal compartment in version A
(EEx de [ib] with Um= 60 V). The flowmeter is connected through a transmitter power supply
("EEx i" approved) in 2-wire mode. If data communication with the flowmeter through the HART®
protocol is required, the transmitter power supply unit must be HART compatible. Terminals I,
Ignd are not polarity sensitive.
The entity parameters of the "EEx i" approved transmitter power supply, including the cable
capacitances and inductances, must fit the entity parameters of the OPTIFLUX 4040 C-EEx
compact flowmeter, namely Ui= 30 V, Ii= 100 mA, Ci= 200 nF, Li= 0. Suitable HART®compatible
transmitter power supplies that can be used in combination of the OPTIFLUX 4040 C-EEx are:
•Phoenix PI/Ex-ME-RPSS-I/I
•CEAG 6/420
Figure 3-2: Connection example in 2-wire mode
1 Hazardous area
2 Safe area
3 Transmitter power supply (EEx i)
4 Process / display unit
5 Hand held terminal
6 OPTIFLUX 4040 C-EEx

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3.5.2 Example of OPTIFLUX 4040 C-EEx in 2x2-wire mode (4-wire)
The diagram shows an example of the connection of the OPTIFLUX 4040 C-EEx in 2x2-wire
mode. As in the previous example, the terminal compartment is again version A.
The additional power supply (terminals 1L=, 0L=) of the OPTIFLUX 4040 C-EEx is supplied by an
external power supply unit through an "EEx i" zener barrier with a linear output load.
The connection of the current output (terminals I, Ignd) and the additional power supply
(terminals 1L=, 0L=) is insensitive for polarity reversal.
Important notes
•Only one of the two connected circuits of the OPTIFLUX 4040 C-EEx, namely the "currrent
output" or the "additional power supply" may be earthed to maintain the required galvanic
separation between the two circuits!
•It is strictly interdicted to use the IMoCOM adapter with the IFC 040-EEx unit!
The voltage of the external power supply unit must be carefully chosen to keep it within the
allowed limits. The upper limit is determined by the maximum working voltage of the zener
barrier, which in general lies a few volts below the maximum open voltage value Uoof the used
zener barrier. The lower limit is determined by the sum of the minimum working voltage of the
additional power supply of the OPTIFLUX 4040 C-EEx flowmeter of 14 V and the voltage drop over
the zenerbarrier caused by the end-to-end resistance of the barrier and (if not neglectable) the
serie cable resistance. This voltage drop can be significant. The above described determination
of the external power supply voltage is explained by the following example.
Figure 3-3: Connection example in 4-wire mode
1 Hazardous area
2 Safe area
3 Transmitter power supply (EEx i)
4 Process / display unit
5 Hand held terminal
6 External power supply
7 Zener barrier
8 OPTIFLUX 4040 C-EEx

ELECTRICAL CONNECTIONS 3
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Example with typical parameters:
The voltage drop across the end-to-end resistance of the zener barrier is 22 mA x 340 Ω= 7.5 V
This means that the external power supply must supply an output voltage to the zener barrier
that lies in the range somewhere between 21.5...25.5 V. The voltage over the terminals of the
additional power supply of the OPTIFLUX 4040 C-EEx is in that case between the required
14.0...18.0 V
Zener barrier data: Uo= 28 V
Io= 93 mA
Maximum working voltage = 25.5 V
End-to-end resistance 340 Ω

4OPERATION
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The OPTIFLUX 4040 C can be programmed in the hazardous area with a bar magnet, without
opening the flameproof housing of the converter. Consult the standard manual for a description
of the software menu.

MAINTENANCE AND SERVICE 5
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5.1 Maintenance
The flowmeters are maintenance free with respect to the flowmetering properties. Within the
scope of periodic inspections required for electrical equipment installed in hazardous areas it is
recommended to check the housing for signs of damage or corrosion. This concerns the
converter housing and the flow sensor housing.
5.2 Replacement of electronics unit
Before opening:
•Make absolutely sure that there is no explosion hazard!
•Gas-free certificate!
•Make sure that all connecting cables are safely isolated from all external sources!
When these instructions are strictly followed, the display cover (with the glass window) can be
removed.
Removal of the electronics unit
•Raise the latch of the interlocking device by loosening the hexagon socket head cap screw
size 3, until the cover can rotate freely.
•Unscrew the cover with the special plastic wrench that is supplied with the device.
•Unscrew the two screws of the display unit and turn it carefully aside.
•Carefully disconnect the 12 pin connector (for field coil and electrode circuits connection)
from the electronics unit.
•Unscrew the two mounting screws of the electronics unit, which fixes the metal frame to the
back of the signal converter housing. A crosshead screwdriver type 2 Pt. Philips is most
suitable.
•Carefully remove the electronics unit of the converter housing. Do not damage any
connecting cables!
Insertion of the electronics unit
•Insert the electronics unit in the converter housing
•Tighten the two mounting screws of the electronics unit.
•The metal frame of the electronics unit must be securely screwed to the housing (back-end of
electronics compartment) by the two non-removable fastening screws. Screw them with a
tightening torque of 1.3 Nm.
•Connect the 12-pin connector.
•Mount the display-unit.
•Before the cover is screwed back into the housing, the screw-thread must be clean and well
greased with an acid and resin-free grease, e.g. silicone grease.
WARNING!
the following instructions must always be carefully followed, if the housing of the signal
converter has to be opened respectively closed again.
WARNING!
These two screw connections also establish the safety-technical connection of the electronics
unit to the signal converter housing and equipotential bonding system.

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•Screw the display cover as tight as possible into the housing by hand, so that the gasket of the
cover must be clamped to provide the required ingress protection (IP) degree.
•Tighten the hexagon socket head cap screw of the interlocking device.
INFORMATION!
Refer to the standard installation and operating instructions for detailed information about
resetting and reprogramming the new electronics unit after replacement.

NOTES 6
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KROHNE product overview
•Electromagnetic flowmeters
•Variable area flowmeters
•Ultrasonic flowmeters
•Mass flowmeters
•Vortex flowmeters
•Flow controllers
•Level meters
•Temperature meters
•Pressure meters
•Analysis products
•Measuring systems for the oil and gas industry
•Measuring systems for sea-going tankers
Head Office KROHNE Messtechnik GmbH
Ludwig-Krohne-Str. 5
D-47058 Duisburg (Germany)
Tel.:[phone]
Fax:[phone]
[email protected]
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