KROHNE OPTISONIC 8300 Wiring diagram

Ultrasonic flowmeter
for high-temperature gas and superheated steam
Addendum for hazardous areas.
These additional instructions are an extension to the OPTISONIC 8300 Quick Start and
Handbook.
OPTISONIC 8300
OPTISONIC 8300OPTISONIC 8300
OPTISONIC 8300
Supplementary Instructions
Supplementary InstructionsSupplementary Instructions
Supplementary Instructions
© KROHNE 03/2020 - 4008065001 - AD EX OPTISONIC 8300 R03

CONTENTS
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OPTISONIC 8300
1 Introduction 4
1.1 Safety instructions from the manufacturer ..................................................................... 4
1.1.1 Copyright and data protection ................................................................................................ 4
1.1.2 Disclaimer ............................................................................................................................... 4
1.1.3 Product liability and warranty ................................................................................................ 5
1.1.4 Information concerning the documentation........................................................................... 5
1.1.5 Warnings and symbols used................................................................................................... 6
1.2 Manufacturer.................................................................................................................... 6
1.3 Safety instructions for the operator................................................................................. 7
1.4 Special conditions for safe use ........................................................................................ 7
1.5 Special notes for safe operation ...................................................................................... 8
1.6 Approval.......................................................................................................................... 10
1.7 OPTISONIC 8000-Ex........................................................................................................ 10
1.8 Ultrasonic gas transducers............................................................................................ 11
1.9 OPTISONIC 8300-Ex........................................................................................................ 11
1.10 GFC 300 F/...-Ex............................................................................................................ 12
1.11 Technical data............................................................................................................... 12
1.12 Marking labels (examples) ........................................................................................... 13
2 Temperature limits 15
2.1 General ........................................................................................................................... 15
2.2 GFC 300 F/...-Ex.............................................................................................................. 15
2.3 OPTISONIC 8000-Ex........................................................................................................ 16
3 Connection of separate systems 17
3.1 General ........................................................................................................................... 17
3.2 Cable marking ................................................................................................................ 17
3.3 Equipotential bonding..................................................................................................... 17
3.3.1 Flow sensor........................................................................................................................... 17
3.3.2 Signal converter.................................................................................................................... 17
3.4 Connection of signal cable to signal converter.............................................................. 18
4 Electrical connections 20
4.1 General ........................................................................................................................... 20
4.2 Cable glands ................................................................................................................... 22
4.3 Field Wiring..................................................................................................................... 22
4.4 Non-"Ex i" I/O connections............................................................................................. 23
4.5 "Ex i" I/O connections.....................................................................................................25

CONTENTS
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OPTISONIC 8300
5 Maintenance 27
5.1 Maintenance ................................................................................................................... 27
5.2 Before and after opening................................................................................................ 27
5.3 Replacement of mains fuse............................................................................................ 28
5.4 Exchange of electronics unit .......................................................................................... 29
5.5 Service / repair information ........................................................................................... 32
5.6 Form (for copying) to accompany a returned device ..................................................... 33
5.7 Disposal .......................................................................................................................... 33
6 Notes 34

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1.1 Safety instructions from the manufacturer
1.1.1 Copyright and data protection
The contents of this document have been created with great care. Nevertheless, we provide no
guarantee that the contents are correct, complete or up-to-date.
The contents and works in this document are subject to copyright. Contributions from third
parties are identified as such. Reproduction, processing, dissemination and any type of use
beyond what is permitted under copyright requires written authorisation from the respective
author and/or the manufacturer.
The manufacturer tries always to observe the copyrights of others, and to draw on works created
in-house or works in the public domain.
The collection of personal data (such as names, street addresses or e-mail addresses) in the
manufacturer's documents is always on a voluntary basis whenever possible. Whenever
feasible, it is always possible to make use of the offerings and services without providing any
personal data.
We draw your attention to the fact that data transmission over the Internet (e.g. when
communicating by e-mail) may involve gaps in security. It is not possible to protect such data
completely against access by third parties.
We hereby expressly prohibit the use of the contact data published as part of our duty to publish
an imprint for the purpose of sending us any advertising or informational materials that we have
not expressly requested.
1.1.2 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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1.1.3 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 or 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.
1.1.4 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 icons as shown below.

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1.1.5 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.
i RESULT
RESULTRESULT
RESULT
This symbol refers to all important consequences of the previous actions.
1.2 Manufacturer
The instrument is developed and manufactured by:
KROHNE Altometer
Kerkeplaat 12
3313 LC Dordrecht
The Netherlands
For information, maintenance or service please contact your nearest local KROHNE
representative.
DANGER!
This warning 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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1.3 Safety instructions for the operator
The instructions in this manual are a necessary extension to the standard documentation and
only apply to the Explosion protected versions of the devices described in this document.
All technical information as described in the standard documentation is applicable, unless
excluded, completed or replaced by the specific directions in this manual.
General
•The relationship between ambient- and/or process temperature and temperature class is
described in this manual.
•For details of the flameproof joints, contact KROHNE Altometer.
•Repairs on the flameproof joints may only be done in accordance with the design
specifications of KROHNE Altometer. A repair on the basis of the values in tables 1 and/or 2
of IEC 60079-1 is not permitted.
1.4 Special conditions for safe use
•High charge generating processes,
•Mechanical friction and separation processes,
•Electron emission (e.g. near electrostatic coating equipment).
Make absolutely sure that the stainless steel protection caps are always installed and properly
secured so that the piezo modules made of bronze are always protected against possible friction
and mechanical impact.
WARNING!
• Do not change the device. Unauthorized changes can have an effect on the explosion safety of
the devices.
• The instructions, precautions and regulations, as well as the electrical data described in the
EU 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-IEC 60364 (e.g. VDE 0100), especially the
regulations in IEC/EN 60079-14 "Electrical installations in hazardous locations" or an
equivalent (national) standard (e.g. DIN VDE 0165 Part 1), must be strictly followed.
• Installation, adjustment, maintenance and operation of the device is only allowed to be done
by sufficient trained personnel with a correct knowledge in explosion safety!
CAUTION!
Prevent the risk of ignition as a result of electrostatic charging!
Do not use the equipment in the following locations:

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1.5 Special notes for safe operation
Connection conditions
1. The OPTISONIC 8000-Ex flow sensor is approved for installation and use in zone 1 and 2
hazardous classified locations. It is also approved to be used in pipe-lines where the inside
is designated as a zone 0 hazardous location. The flow sensor is not
notnot
not allowed to be installed and
operated in a Zone 0 hazardous location.
2. When the terminal compartment of the GFC 300 F/…-Ex is designed in “Ex db”type of
protection, the following must be complied with:
•The device shall be connected with suitable cable glands or conduit systems that meet the
requirements stipulated in IEC/EN 60079-1, and for which a separate test certificate has been
issued. If the device is connected to conduit systems, the required sealing device
shall be provided immediately at the cable entrance(s) of the enclosure.
•Cable glands and blanking plugs of simple design should not be used.
•Openings that are not used shall be sealed in compliance with the specifications in
IEC/EN 60079-1.
•If the electrical connection is made in the potentially explosive area, the connecting cable
(unconnected cable end) of the remote ultrasonic flow meter system shall be connected in an
enclosure that meets the requirements of an approved type of protection in accordance with
IEC/EN 60079-0.
3. The connecting cable of this remote high-temperature gas/steam ultrasonic flow meter
system (OPTISONIC 8300) shall be fixed and routed so that it will be adequately protected
against damage.
4. The connecting cable(s) of type 2-pole RG316 Triax (Habia RGT 316 STR 2 + dr) that are supplied
with the OPTISONIC 8300 flow meter system are rated for a continuous operating temperature of
maximum 100°C.
The maximum temperatures listed in the temperature classification tables are limited
(refer to
Temperature limits on page 15) and based on the maximum operating
temperature of the connecting cable(s), cable gland(s) and/or blind plug (in case of a single-beam
sensor.
5. The flameproof (Ex d) circular connection box shall always be provided with ATEX and IECEx ap-
proved flameproof cable glands with screw-thread size M20 x 1.5 - 6 g. The by KROHNE
delivered “Ex d”approved cable glands of type A2F (manufacturer CMP) are provided with the
default sealing rubber and are suitable for temperatures ranging from -60°C up to +130°C.
6. The OPTISONIC 8300 system, composed of OPTISONIC 8000-Ex flow sensor and GFC 300 F/…-
Ex flow converter, shall be incorporated into the local equipotential bonding system of the
potentially explosive area.
These notes and instructions shall accompany each device in an adequate form. Components
attached or installed (i.e. terminal compartments, bushings, Ex-type cable glands, connectors,
etc.) shall be of a technical standard that complies with the specifications on the cover sheet and
shall have a separate examination certificate. The operating conditions specified in the component
certificates must be complied with.

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Warning messages
In potentially explosive atmospheres, the enclosure may only be opened after it has been
de-energized and the required waiting time has been obeyed (warning sign!).
For the OPTISONIC 8000-Ex steam/gas flow sensor, no waiting time is required
The warning message reads as follows:
WARNING ! - Do not open when energized.
WARNING ! - Do not open when energized.WARNING ! - Do not open when energized.
WARNING ! - Do not open when energized.
The GFC 300 F/…-Ex flow converter has a waiting time of 35 minutes for temperature class T6
and 10 minutes for temperature class T5. No waiting time has to be considered for T4 up to and
including T1. The warning message reads as follows:
WARNING ! - Do not open flameproof enclosure when energized.
WARNING ! - Do not open flameproof enclosure when energized.WARNING ! - Do not open flameproof enclosure when energized.
WARNING ! - Do not open flameproof enclosure when energized.
Minimum waiting time before opening: T6 = 35 min., T5 = 10 min.
Minimum waiting time before opening: T6 = 35 min., T5 = 10 min.Minimum waiting time before opening: T6 = 35 min., T5 = 10 min.
Minimum waiting time before opening: T6 = 35 min., T5 = 10 min.

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1.6 Approval
The OPTISONIC 8300 ultrasonic gas/steam flowmeters are manufactured according to the
European Directive 2014/34/EU and IECEx 02 Certification System. The flowmeters are approved
for installation and use in hazardous classified locations of zone 1 and 2 and are in accordance
with the European standards of the IEC/EN 60079 series:
The inside of the pipe-line is allowed to be designated as a zone 0 hazardous location. The
explosion safety of the OPTISONIC 8000-Ex sensor is not negatively influenced by this due to its
construction. The sensor is not permitted to be installed in a zone 0 hazardous location.
The OPTISONIC 8000-Ex gas/steam ultrasonic flow sensor, which is only available in remote
design, has the following approval number(s):
KIWA 17ATEX0025 X
KIWA 17ATEX0025 XKIWA 17ATEX0025 X
KIWA 17ATEX0025 X and IECEx KIWA 17.0011X
IECEx KIWA 17.0011XIECEx KIWA 17.0011X
IECEx KIWA 17.0011X
1.7 OPTISONIC 8000-Ex
The OPTISONIC 8000-Ex high temperature gas/steam flow sensor is for measuring high
temperature gases including steam. The thermal sensitive parts of the transducer are located at
a larger distance from the process medium inside the measuring tube. There are 2 versions:
•version with a rectangular aluminium connection box and flameproof connectors
•version with a flameproof (Ex db) circular stainless steel connection box
The high-temperature gas/steam ultrasonic transducers are equipped with flameproof piezo
modules in which the electrical connections via SMB-connectors are made.
The marking code of both versions is:
IEC60079-0:2011/EN60079-0:2012+A11 Equipment - General Requirements
IEC60079-1:2014/EN60079-1:2014 Equipment protected by flameproof enclosures "d"
IEC60079-26:2014/EN60079-26:2015 Equipment with Equipment Protection Level (EPL) Ga
OPTISONIC 8000-Ex
II 1/2 G Ex db T6...T1, 550°C, 615°C Ga/Gb

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1.8 Ultrasonic gas transducers
The OPTISONIC 8000-Ex gas flow sensor, can be equipped with the following types of
high-temperature gas/steam ultrasonic transducers, made of:
•stainless steel
•inconel 625
The back-end of the transducer is provided with a flameproof piezo module for the electrical
connection via SMB-connectors.
There are two variants of the high-temperature gas/steam ultrasonic transducers:
•Reso-type (uses resonance decoupling)
•Foil Wave Guide (FWG) type
Both types use a different piezo module and have a type of protection flameproof enclosure
according to IEC/EN 60079-1.
1.9 OPTISONIC 8300-Ex
The OPTISONIC 8300-Ex is the remote configuration of the GFC 300 F/...-Ex ultrasonic flow
converter and the OPTISONIC 8000 ultrasonic gas/steam flow sensor.
The OPTISONIC 8300-Ex flow sensor is connected to the converter by one (in case of a single-
beam sensor) or two (for a dual-beam sensor) cables of type 2-pole RG316 triax (Habia RGT 316
STR 2 + dr).
The GFC 300 F/...-Ex flow converter has flameproof protected electrical connections to the
flameproof piezo modules of the high-temperature gas/steam transducers of the sensor. The
converter has
non-Ex or intrinsically safe (Ex ia) in-/outputs. The connection terminals of these in-/outputs are
located in the terminal compartment, which is configured as “Ex d”or “Ex e”.
See the next section(s) for more information of the GFC 300 F/…-Ex converter.

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1.10 GFC 300 F/...-Ex
The GFC 300 F/...-Ex is the remote version of the ultrasonic flow converter and has flameproof
protected connections to the flameproof gas transducers of the ultrasonic flow sensor.
The ultrasonic gas flow converter is either provided with non-explosion protected or intrinsically
safe in-/outputs (“Ex ia”or “Ex ib”). The connection terminals of these in-/outputs are located in
the terminal compartment, which is either configured as “Ex d”or “Ex e”.
The marking code can be:
Approvals
The GFC 300 F/…-Ex ultrasonic gas flow converter in remote design is manufactured according
to the European Directive 2014/34/EU and IECEx 02 Certification System.
The converter is approved for installation and use in hazardous classified locations of Zone 1 and
2 in accordance with the below listed international and European Standards.
The GFC 300 F/…-Ex ultrasonic flow converter has the following approval numbers:
KIWA 17ATEX0002 X
KIWA 17ATEX0002 XKIWA 17ATEX0002 X
KIWA 17ATEX0002 X and IECEx KIWA 17.0001X
IECEx KIWA 17.0001XIECEx KIWA 17.0001X
IECEx KIWA 17.0001X
1.11 Technical data
Converter type "Ex db" terminal compartment "Ex eb" terminal compartment
GFC 300 F-Ex II 2 G Ex db IIC T6 Gb II 2 G Ex db eb IIC T6 Gb
GFC 300 F/i-Ex II 2 (1) G Ex db [ia Ga] IIC T6 Gb II 2 (1) G Ex db eb [ia Ga] IIC T6 Gb
IEC60079-0:2011/EN60079-0:2012+A11: 2013 Equipment - General Requirements
IEC60079-1:2014/EN60079-1:2014 Equipment protected by flameproof enclosures "d"
IEC60079-7:2006/EN60079-7:2007 Equipment protected by increased safety "e"
IEC60079-11:2011/EN60079-11:2012 Equipment protected by increased safety "i"
Process medium Flammable and non-flammable gases
Protection category acc. to
IEC/EN 60529 IP66/IP67
Ambient temperature range Signal converter GFC 300 F/...-Ex: -40...+65°C
1
OPTISONIC 8000-Ex : -40...+70°C
Process medium temperature range -25...+600°C
INFORMATION!
1
Maximum ambient temperature of 65 º C applies to the aluminum MH 300-Ex converter
housing. The stainless steel version of this housing is limited to +60
º C.

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1.12 Marking labels (examples)
The marking labels shown here are configuration examples.
Figure 1-1: Example of the nameplate for the OPTISONIC 8000-Ex flow sensor
1 Specific sign for explosion protection, Ex codes and number of EC type examination certificate
2 Explosion safety notes
3 Tag number
4 PED data, year of manufacturing and country of origin
5 Protection class and calibration data
6 Type designation of the flow meter, disposal logo and CE sign with number(s) of notified body / bodies.
7 Name and address of the manufacturer.
Figure 1-2: Example of the nameplate for the GFC 300 F-Ex flow converter
1 Specific sign for explosion protection, Ex codes and number of EC type examination certificate
2 Additional information
3 Explosion safety notes and warning messages
4 Protection class and Tag number
5 Main supply data
6 Calibration data / CG number
7 Manufacturer website, info and disposal logo
8 Type designation of the flow meter, manufacturing date and CE sign with number(s) of notified body / bodies.
9 Name and address of the manufacturer.

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The I/O sticker is placed on the inside of the module terminal compartment;
•Fieldbus IO PA on IO board 1
•Intrinsic safety option with current out active
•Pulse/Status Out/Control in on IO board 2
Other combinations are possible. See the approval description of the GFC 300 electronics unit.
Figure 1-3: Example of the nameplate for the GFC 300 F/i-Ex flow converter
1 Specific sign for explosion protection, Ex codes and number of EC type examination certificate
2 Ex specific remarks
3 Explosion safety notes and warning messages
4 Protection class and Tag number
5 Main supply data
6 Calibration data / CG number
7 Manufacturer website, info and disposal logo
8 Type designation of the flow meter, manufacturing date and CE sign with number(s) of notified body / bodies.
9 Name and address of the manufacturer.
I/O sticker
Figure 1-4: Example of I/O sticker on cover of terminal compartment

TEMPERATURE LIMITS 2
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2.1 General
Due to the influence of the process medium (gas/steam) temperature, the ultrasonic flow
sensors in remote design are not allocated to any fixed temperature class.
The temperature limits apply under the following conditions:
•The instrument is installed and operated in accordance with the installation directions given
in the quick start and / or handbook.
•The instrument is not heated up by any additional heat radiation (direct solar radiation, heat
from adjacent plant parts) causing it to operate above the permissible ambient temperature
range.
•The ultrasonic transducers (piezo modules) do not dissipate any significant power under
normal operating conditions and therefore practically do not generate heat. All defined
temperature classes are a consequence of the applied process temperature in combination
with the ambient temperature.
•Insulation is not hindering free ventilation of the ultrasonic signal converter housing.
2.2 GFC 300 F/...-Ex
The GFC 300 F/...-Ex signal converter has a temperature classification of T6 (85°C).
The permissible ambient temperature is dependent on the material that the MH 300-Ex
electronics housing is made of, namely:
•die-casted aluminum: -40...+65ºC
•die-casted stainless steel: -40...+60ºC

2TEMPERATURE LIMITS
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2.3 OPTISONIC 8000-Ex
The OPTISONIC 8000-Ex high temperature (gas/steam) flow sensor is suitable for an ambient
temperature in the range of -40...+70°C. The maximum process medium temperature is listed in
the tables below.
Temperature class Maximum process temperature [ºC] at
T
a
d40ºCT
a
d50ºCT
a
d60ºCT
a
d65ºCT
a
d70ºC
T6 80 80 80 80 80
T5 95 95 95 95 95
T4 130 130 130 130 130
T3 195 195 195 195 195
T2 290 290 290 290 290
T1 440 440 410 355 305
550ºC540 520 410 355 305
615ºC600 520 410 355 305
Table 2-1: Temperature classification without heat insulation
Temperature class Maximum process temperature [ºC] at
T
a
d40ºCT
a
d50ºCT
a
d60ºCT
a
d65ºCT
a
d70ºC
T6 80 80 80 80 80
T5 95 95 95 95 95
T4 130 130 130 130 130
T3 195 195 195 195 195
T2 290 290 290 290 290
T1 440 440 440 440 375
550ºC540 540 520 445 375
615ºC600 585 520 445 375
Table 2-2: Temperature classification with heat insulation

CONNECTION OF SEPARATE SYSTEMS 3
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3.1 General
The electrical connection between OPTISONIC 8000-Ex ultrasonic (gas/steam) flow sensor and
GFC 300 F/...-Ex ultrasonic signal converter is established via one (single beam versions) signal
cable of type "2 -pole RG316 Triax", or two (dual beam) signal cable(s).
This cable consists of two Triax cables (double shielding) surrounded by an additional screen and
outer insulation layer. The ends of the cables are provided with SMB connectors. .
Depending on version, both cable ends of the non-"Ex d" connection box and console are
provided with SMB plugs and are integrated into the special flameproof connectors.
The signal cable(s) is (are) included with the remote system.
3.2 Cable marking
The coaxial transducer cables are marked at each end by yellow tubing with a black number
of subsequently 1.1 and 1.2 for a single-beam design and numbers 1.1, 1.2, 2.1 and 2.2 for a
double-beam design. The first number represents the path, 1 (single-beam) or 2 (double-beam)
and the second the position of the transducer of that path (1 or 2). The marking of the SMB
counter-plugs in the connection box is identical to that of the transducers cables (1.1, 1.2, ...).
3.3 Equipotential bonding
3.3.1 Flow sensor
The transducer circuits are galvanically isolated from earth and therefore an equipotential
bonding conductor between the ultrasonic flow sensor and the ultrasonic signal converter does
not have to be connected but can be used if necessary.
Where screened signal cable is used, the screen should only be earthed at the flow sensor end.
In the special case of a screen being earthed at both ends of the system, a potential difference
between the sensor and converter is not permitted. Refer to IEC/EN 60079-14 for further
requirements of cable screens.
3.3.2 Signal converter
The GFC 300 F/...-Ex ultrasonic signal converter must
mustmust
must be incorporated in the equipotential
bonding system of the installation. This can be established by connecting a separate
equipotential bonding conductor to the external U-clamp screw terminal (size M5) on the
mounting support of the converter.
The separate bonding conductor must be at least 4 mm
2
(11 AWG) or 2.5 mm
2
(14 AWG), in case
it is mechanically protected, see standard HD-IEC 60364 for details. Make sure that the core of
the bonding wire is properly mounted under the U-clamp of the PE-terminal and that the screw
is tightly fixed.
The transducer circuits of the signal converter are galvanically isolated from earth, therefore an
equipotential bonding conductor between the flow sensor and the signal converter does not have
to be connected, but can be used if necessary (e.g. for EMC reasons).

3CONNECTION OF SEPARATE SYSTEMS
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3.4 Connection of signal cable to signal converter
The flow sensor is connected to the signal converter via one or two signal cables, with 2 inner
Triax cables for the connection of one or two acoustic path(s). A flow sensor with one acoustic
path has one cable. A flow sensor with two acoustic paths has two cables.
Figure 3-1: Connection of signal cable to signal converter
1 Signal converter
2 Open connection box
3 Tool for releasing connectors
4 Marking on cable
5 Insert cable (1 path flowmeter) or cables (2 path flowmeter) through cable glands
CAUTION!
To ensure smooth functioning, always use the signal cable(s) included in the delivery.
Figure 3-2: Clamp the cables on the shielding bush
1 Cables
2 Cable glands
3 Grounding clamps
4 Cable with metal shielding bush

CONNECTION OF SEPARATE SYSTEMS 3
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Figure 3-3: Connect the cables in the connection box of the sensor
INFORMATION!
Connect the cable on connector with similar numeral marking

4ELECTRICAL CONNECTIONS
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4.1 General
The display cover seals the electronics compartment of the converter housing and provides type
of protection “flameproof enclosure”(Ex db) according to IEC/EN 60079-1. The terminal
compartment is either in type of protection "increased safety" or performed as "flameproof
enclosure". The threaded joints formed by the covers and housing are a tight fit due to the
requirements for type of protection “flameproof enclosure”. Screw the covers on and off with
care and never use excessive force!
Keep the screw-threads free of dirt and well-greased (e.g. with PTFE grease). The grease will
help to prevent the threads from locking due to corrosion.
To unscrew the covers, first release the interlocking devices (one at each cover). Therefore
unscrew the M4 head screw with an internal hexagon socket set using a No. 3 Allen key until the
interlocking device can be turned. After the covers are screwed back onto the housing, make
sure that the interlocking devices are properly refitted.
WARNING!
Allow the electronics to de-energize before opening the electronics compartment of the flow
converter housing. Wait at least 35 minutes for T6 and 10 minutes for T5 before opening.
INFORMATION!
Cables and cable glands must be suitable for at least 75
° C when the ambient temperature
exceeds 60
° C. The connecting wires must be stripped over a length of 8 mm and the screws of
the terminal block must be fastened with a torque between 0.6 and 0.8 Nm.
Figure 4-1: Electrical connections
1 Unscrew interlocking head screw
2 Turn cover counter-clockwise and remove
3 Open / close safety lid of mains supply section
4 Mains supply & signal / data terminals