KROHNE OPTIWAVE 7300 C Wiring diagram

Radar (FMCW) Level Transmitter for agitated liquids in
process applications
Supplementary Instructions for IECEx applications
Supplementary Instructions for IECEx applicationsSupplementary Instructions for IECEx applications
Supplementary Instructions for IECEx applications
OPTIWAVE 7300 C
OPTIWAVE 7300 COPTIWAVE 7300 C
OPTIWAVE 7300 C Supplementary instructions
Supplementary instructionsSupplementary instructions
Supplementary instructions
© KROHNE 07/2015 - 4000176503 - AD IECEX OPTIWAVE7300 R03 en

CONTENTS
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OPTIWAVE 7300 C
1 General safety information 4
1.1 Scope of the document..................................................................................................... 4
1.2 Device description ............................................................................................................ 4
1.3 Standards and approvals.................................................................................................. 4
1.4 Equipment protection levels (EPL)................................................................................... 5
1.4.1 Ex ia-approved devices ........................................................................................................... 5
1.4.2 Ex ia/d-, Ex d ia- and Ex ia tb-approved devices .................................................................... 6
1.4.3 Definitions of equipment protection levels ............................................................................ 7
1.5 IECEx nameplates ............................................................................................................ 7
2 Installation 8
2.1 Special conditions............................................................................................................. 8
2.2 Precautions....................................................................................................................... 8
2.2.1 General notes.......................................................................................................................... 8
2.2.2 Electrostatic discharge........................................................................................................... 8
2.2.3 Special conditions ................................................................................................................... 9
2.2.4 Optional purging system....................................................................................................... 10
2.3 Operating conditions ...................................................................................................... 10
2.3.1 Ambient and flange temperature ......................................................................................... 10
2.3.2 Maximum surface temperature of the housing ................................................................... 13
3 Electrical connections 14
3.1 General notes ................................................................................................................. 14
3.2 Terminal compartment .................................................................................................. 14
3.2.1 How to open the terminal compartment .............................................................................. 14
3.2.2 How to close the terminal compartment ............................................................................. 15
3.3 Terminal tightening capacity.......................................................................................... 15
3.4 Equipotential bonding system........................................................................................ 16
3.5 Ex ia equipment .............................................................................................................. 16
3.5.1 How to connect the electrical cables ................................................................................... 16
3.5.2 Maximum intrinsically-safe values for the electrical circuit............................................... 17
3.5.3 Supply voltage ....................................................................................................................... 17
3.5.4 Electrical schematic ............................................................................................................. 17
3.6 Ex ia/d, Ex d ia and Ex ia tb equipment .......................................................................... 18
3.6.1 General notes........................................................................................................................ 18
3.6.2 How to connect the electrical cables ................................................................................... 18
3.6.3 Supply voltage ....................................................................................................................... 19
3.6.4 Electrical schematic ............................................................................................................. 20
4 Start-up 21
5 Service 22
5.1 Periodic maintenance..................................................................................................... 22
5.2 Keep the device clean..................................................................................................... 22
5.3 How to remove the device .............................................................................................. 22

CONTENTS
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OPTIWAVE 7300 C
5.4 Returning the device to the manufacturer..................................................................... 23
5.4.1 General information.............................................................................................................. 23
5.4.2 Form (for copying) to accompany a returned device............................................................ 24
6 Notes 25

1 GENERAL SAFETY INFORMATION
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1.1 Scope of the document
These instructions are applicable only to the explosion-protection version of the radar level
transmitter. For all other data, use the Quick Start and Handbook. If you do not have these
documents, please contact the nearest office or download them from the manufacturer's
internet site.
1.2 Device description
This device is a 2-wire level transmitter that uses FMCW (Frequency-Modulated Continuous
Wave) radar technology. It measures level, volume, distance to surface and reflectivity of liquids,
pastes and slurries. It is suitable for installation on storage tanks, process tanks and stilling
wells. Measurements are displayed via a DTM (device type manager) for remote communication
or on an optional integrated display screen with wizard-driven setup and online help functions.
The level transmitter is approved for use in potentially explosive atmospheres when equipped
with the appropriate options.
1.3 Standards and approvals
The certificate is given on the CD-ROM supplied with the device. You can also download the
certificate from our internet site.
INFORMATION!
The information in these supplementary instructions only contains the data applicable to
explosion protection. The technical data for the non-Ex version in the Handbook shall be valid in
its current version, provided that it is not rendered invalid or replaced by these supplementary
instructions.
WARNING!
Installation, commissioning and maintenance may only be carried out by "Personnel trained in
explosion protection".
DANGER!
In compliance with IECEx scheme rules, the IECEx version of the device described in these
Supplementary Instructions conforms to International Standards IEC 60079-0:2011, IEC 60079-
1:2007, IEC 60079-11:2011, IEC 60079-26:2006, IEC 60079-31:2013. The Ex ia, Ex ia/d, Ex d ia and
Ex ia tb versions are certified for use in hazardous areas by DEKRA Certification B.V. under
IECEx KEM 06.0025X.
WARNING!
Carefully read the IECEx approval certificate. Obey the boundary conditions.

GENERAL SAFETY INFORMATION 1
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1.4 Equipment protection levels (EPL)
1.4.1 Ex ia-approved devices
The Ex ia-approved device has the marking that follows for Gas Groups:
PP Drop antenna version
•Ex ia IIC T6...T4 Ga
All other versions
•Ex ia IIC T6...T3 Ga
The Ex ia-approved device is suitable for use in potentially explosive atmospheres of all
flammable substances in Gas Groups IIA, IIB and IIC. It is certified for applications requiring EPL
Ga or EPL Ga/Gb or EPL Gb equipment, when fitted with the appropriate options. It also agrees
with temperature class T2 and T1 (Gas Groups) if the temperature limits are obeyed. For more
data, refer to
Ambient and flange temperature on page 10.
EPL Ga equipment are used in zone 0. EPL Ga/Gb equipment are used in zone 0, but they are
installed in the boundary wall between zone 0 and zone 1 (the antenna is in zone 0 and the signal
converter is in zone 1). EPL Gb equipment are used in zone 1.
The Ex ia-approved device has the marking that follows for Dust Groups:
•Ex ia IIIC T95°C Da
The Ex ia-approved device is suitable for use in potentially explosive atmospheres of all
flammable substances in Dust Groups IIIA, IIIB and IIIC. It is certified for applications requiring
EPL Da or EPL Da/Db or EPL Db equipment, when fitted with the appropriate options. The
surface temperature of the housing (without a layer of dust) cannot be more than +95°C / +203°F
when the ambient temperature is +80°C / +176°F.
Category 1 D equipment are used in zone 20. EPL Da/Db equipment equipment are used in zone
20, but they are installed in the boundary wall between zone 20 and zone 21 (the antenna is in
zone 20 and the signal converter is in zone 21). EPL Db equipment are used in zone 21.
WARNING!
Make sure that the installation of the device between zone 0 and zone 1 agrees with IEC 60079-
26.

1 GENERAL SAFETY INFORMATION
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1.4.2 Ex ia/d-, Ex d ia- and Ex ia tb-approved devices
The Ex ia/d- and Ex d ia-approved device has the marking that follows for Gas Groups:
PP Drop antenna version
•Ex ia/d IIC T6...T4 Ga/Gb
All other versions
•Ex ia/d IIC T6...T3 Ga/Gb
Ex ia/d and Ex d ia-approved devices are suitable for use in potentially explosive atmospheres of
all flammable substances in Gas Groups IIA, IIB and IIC. They also agree with temperature class
T2 and T1 (Gas Groups) if the temperature limits are obeyed. For more data, refer to
Ambient
and flange temperature
on page 10.
EPL Ga/Gb equipment are used in zone 0, but they are installed in the boundary wall between
zone 0 and zone 1 (the antenna is in zone 0 and the signal converter is in zone 1). EPL Gb
equipment are used in zone 1.
The Ex ia tb-approved device has the marking that follows for Dust Groups:
All other versions
•Ex ia tb IIIC T95°C Da/Db
The Ex ia tb-approved device is suitable for use in potentially explosive atmospheres of all
flammable substances in Dust Groups IIIA, IIIB and IIIC. It is certified for applications requiring
EPL Da/Db or EPL Db equipment, when fitted with the appropriate options. The surface
temperature of the device (without a layer of dust) cannot be more than +95°C / +203°F when the
ambient temperature is +80°C / +176°F.
EPL Da/Db equipment are used in zone 20, but they are installed in the boundary wall between
zone 20 and zone 21 (the probe is in zone 20 and the signal converter is in zone 21). EPL Db
equipment are used in zone 21.
INFORMATION!
Ex ia/d and Ex d ia approvals
Ex ia/d and Ex d ia approvalsEx ia/d and Ex d ia approvals
Ex ia/d and Ex d ia approvals
Only the marking for the Ex ia/d approval is shown on the nameplate. If the device has an Ex ia/d
approval marking on the nameplate then it also has the Ex d ia approval. This document gives
data about the two approvals.
The Ex ia/d approval is applicable to EPL Ga/Gb equipment, when the device is fitted with the
appropriate options. The Ex d ia approval is applicable to EPL Gb equipment, when the device is
fitted with the appropriate options.

GENERAL SAFETY INFORMATION 1
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1.4.3 Definitions of equipment protection levels
EPL Ga or Da
EPL Ga or DaEPL Ga or Da
EPL Ga or Da
The device is installed in hazardous areas that must have equipment with a very high level of
protection. The device is not a source of ignition in usual conditions of operation or when
possible or unusual faults occur.
EPL Gb or Db
EPL Gb or DbEPL Gb or Db
EPL Gb or Db
The device is installed in hazardous areas that must have equipment with a high level of
protection. The device is not a source of ignition in usual conditions of operation or when
possible faults occur. It is possible that this does not include frequent faults.
1.5 IECEx nameplates
Figure 1-1: Nameplate on the signal converter housing
1 IECEx certification agency code
2 Equipment protection level, types of device protection including approved Gas Groups and temperature classes
Equipment protection level, types of device protection including approved Dust Groups and maximum surface temper-
ature
3 Ex ia approvals:
Ex ia approvals:Ex ia approvals:
Ex ia approvals: Intrinsically-safe circuit data
Ex ia/d or Ex ia tb approvals:
Ex ia/d or Ex ia tb approvals:Ex ia/d or Ex ia tb approvals:
Ex ia/d or Ex ia tb approvals: Maximum voltage in accordance with IEC 60079-0. Refer to 7for the input voltage range.
4 Ex ia/d or Ex ia tb approvals:
Ex ia/d or Ex ia tb approvals:Ex ia/d or Ex ia tb approvals:
Ex ia/d or Ex ia tb approvals: Minimum waiting time after the device is de-energized before it is safe to open the ter-
minal compartment
5 Cable entry type and size (M20×1.5, M25×1.5, ½NPT or G ½)
6 Input voltage range and maximum current (4...20 mA passive –HART)

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2.1 Special conditions
This device can be installed on the applicable auxiliary equipment: a bypass chamber, a stilling
well or a communicating pipe.
2.2 Precautions
2.2.1 General notes
Make sure that:
•you can get access to the device,
•there is sufficient space around the device for inspections
•you can see the device nameplate, and
•there are no external forces applied on the device.
2.2.2 Electrostatic discharge
WARNING!
When you install the device, obey the conditions in the IECEx approval certificate. These
conditions include:
• The special conditions for safe use.
• The Essential Health and Safety Requirements.
The certificate is given on the DVD-ROM supplied with the device. You can also download the
certificate from our internet site.
DANGER!
This installation must agree with IEC 60079-14: Explosive atmospheres
– Part 14: Electrical
installations design, selection and erection.
DANGER!
Risk of electrostatic discharge from painted surfaces, the blue plastic sun cover, the hygienic
antenna, the Drop antenna and the flange plate protection (if the Drop antenna has this option).
Make sure that all personnel and equipment are correctly grounded.
DANGER!
Take the necessary antistatic precautions if:
• you handle the device in potentially explosive atmospheres,
• you install the device in potentially explosive atmospheres or
• you use the device in potentially explosive atmospheres.
Install the device correctly to prevent electrostatic discharge. Make sure that all equipment is
correctly grounded.
Make sure that the housing and adjacent objects do not rub together.
If dirt collects on the device, clean it with a damp cloth.

INSTALLATION 2
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Do not install in a location where the electrostatic charge can increase. This includes:
•locations near ventilation systems,
•locations where there is a risk of an increase in electrostatic charge caused by compressed
air and dust,
•locations near machines that use friction,
•locations near systems that apply electrons as a spray (e.g. near electrostatic painting
systems), and
•locations near other machines and systems that can have large electrostatic charges.
2.2.3 Special conditions
Figure 2-1: ESD warning sticker (below the device nameplate)
1 Text: Plastic Parts
2 Text: Warning! Potential electrostatic hazard –see instructions
Figure 2-2: Risk of ESD
1 Sun cover
2 Drop antenna
3 Flange plate protection (option for the Drop antenna)
WARNING!
Aluminium housing: Possible source of ignition in a potentially explosive atmosphere where it is
necessary to use EPL Ga equipment. The housing is made of either aluminium alloy or stainless
steel. If the device has an aluminium alloy housing, make sure that iron/steel objects do not hit
or rub against the device.
INFORMATION!
The display agrees with the low-energy impact test requirements.

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2.2.4 Optional purging system
The purging system is supplied as an option for devices that have horn antennas.
Connection and operation of the purging connection are the responsibility of the user. The
operator is also responsible for selection of a suitable fluid to purge the device.
• If the screw is removed, make sure that the installation agrees with the Ex requirements for
the purging system.
2.3 Operating conditions
The allowable ambient temperature and corresponding flange temperature range for the device
depends on the Ex equipment category and temperature classes marked on the nameplate.
2.3.1 Ambient and flange temperature
Because product temperature has an effect on the device, more than one temperature class is
given. The temperature class is related to the product temperature and the temperature of the
adjacent area.
Figure 2-3: Optional purging system
1 ¼NPTF purging connection (optional)
INFORMATION!
If delivered with the device, the purging connection is plugged with a
¼ NPTF screw and engaged
on a minimum of 3
½ threads.
WARNING!
The gasket temperature must be in the approved limits. For more data, refer to "Pressure and
temperature ranges" in the Installation chapter of the handbook.
WARNING!
The reference point for the process temperature is the flange facing (flanges) or the thread stop
(threaded connections) of the device. In the tables that follow, this reference point will be
referred to as the "flange temperature".

INSTALLATION 2
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The maximum permitted process temperatures are applicable in these conditions. Refer also to
the tables that follow.
•Device installation must agree with the instructions given in the handbook.
•Make sure that the device temperature does not increase because of other heat sources
(sunlight, adjacent system components etc.). The device must not be operated above the
maximum permitted ambient temperature.
•Do not put insulation around the signal converter. Make sure that the airflow around the
signal converter is sufficient. It is permitted to have insulation on the pipe (stilling well) and
the flange.
EPL Ga: Ex ia devices only
EPL Ga/Gb: Ex ia and Ex ia/d devices
WARNING!
An explosive atmosphere is a mixture of air and flammable gases, vapour, mist or dust in
atmospheric conditions. If you do not use the device in these conditions (T
atm
= -20...+60 ° C/
-4...+140
° F and p
atm
= 0.8...1.1 barg / 11.60...15.95 psig), do an analysis of the risk of ignition.
T
atm
= atmospheric temperature and p
atm
= atmospheric pressure.
WARNING!
If the device must operate at a high process temperature, make sure that the maximum flange
temperature and maximum ambient temperature are not more than the values given in the
table.
Temperature
class
Ambient temperature Flange temperature
(process temperature)
[°C] [°F] [°C] [°F]
T6 -20…+57 -4…+122 -20…+60 -4…+140
Temperature
class
Ambient temperature Flange temperature
(process temperature)
[°C] [°F] [°C] [°F]
T6 -40…+57 -40…+134 -20…+60 -4…+140
T5 -40…+72 -40…+161 -20…+60 -4…+140
T4 -40…+80 -40…+176 -20…+60 -4…+140

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EPL Gb: Ex ia and Ex d ia devices
EPL Da: Ex ia devices only
EPL Da/Db, EPL Db: Ex ia and Ex ia tb devices
Temperature
class
Ambient temperature Flange temperature
(process
temperature)
Hygienic antennas Drop and horn
antennas
Drop and horn
antennas with the
distance piece
[°C] [°F] [°C] [°F] [°C] [°F] [°C] [°F]
T6 -40…+57 -40…+134 -40…+57 -40…+134 -40…+57 -40…+134 -50…+60
1
-58…+140
1
-40…+50 -40…+122 -40…+47 -40…+116 -40…+51 -40…+124 -50…+85
1
-58…+185
1
T5 -40…+72 -40…+161 -40…+72 -40…+161 -40…+72 -40…+161 -50…+75
1
-58…+167
1
-40…+65 -40…+149 -40…+62 -40…+143 -40…+66 -40…+151 -50…+100
1
-58…+212
1
T4 2 -40…+80 -40…+176 -40…+80 -40…+176 -40…+80 -40…+176 -50…+85
1
-58…+185
1
-40…+76 -40…+169 -40…+74 -40…+165 -40…+79 -40…+174 -50…+100
1
-58…+212
1
-40…+73 -40…+163 -40…+70 -40…+158 -40…+74 -40…+165 -50…+110
1
-58…+230
1
-40…+66 -40…+151 -40…+60 -40…+140 -40…+68 -40…+154 -50…+135
1
-58…+275
1
T3 3 -40…+62 -40…+143 -40…+54 -40…+129 -40…+64 -40…+147 -50…+150
1
-58…+302
1
— — — — -40…+57 -40…+134 -50…+180
1
-58…+356
1
— — — — -40…+52 -40…+125 -50…+200
1
-58…+392
1
1Min. -50°C/-58°F, if an EPDM gasket is used. Min. -20°C/-4°F, if a Kalrez®6375 gasket is used. Min. -40°C/-40°F, if an FKM/FPM
gasket is used. Min. -30°C/-22°F, if a Metaglas®feedthrough is used. Min. -50°C/-58°F, if a PEI feedthrough is used.
2Max. flange temperature is +100°C / +212°F, if the PP Drop antenna used
3Do not use this temperature class for the PP Drop antenna. Max. flange temperature is +150°C / +302°F, if the PTFE Drop antenna or
Hygienic antenna are used.
Ambient temperature Flange temperature (process temperature)
[°C] [°F] [°C] [°F]
-40…+80 -40…+176 -50…+200 1 -58…+392 1
1Max. flange temperature is +100°C / +212°F, if PP Drop antenna used. Max. flange temperature is +150°C / +302°F, if the PTFE Drop or
the Hygienic antenna is used. Min. -50°C/-58°F, if an EPDM gasket is used. Min. -20°C/-4°F, if a Kalrez®6375 gasket is used. Min. -
40°C/-40°F, if an FKM/FPM gasket is used. Min. -30°C/-22°F, if a Metaglas®feedthrough is used. Min. -50°C/-58°F, if a PEI
feedthrough is used.

INSTALLATION 2
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2.3.2 Maximum surface temperature of the housing
EPL Da: Ex ia devices only
EPL Da/Db, EPL Db: Ex ia and Ex ia tb devices
Max. ambient temperature Max. flange
temperature
Max. surface
temperature
Hygienic antennas Drop and horn
antennas
Drop and horn
antennas with the
distance piece
[°C] [°F] [°C] [°F] [°C] [°F] [°C] [°F] [°C] [°F]
+60 +140 +60 +140 +60 +140 +60 +140 +67 +153
+75 +167 +75 +167 +75 +167 +75 +167 +82 +180
+80 +176 +80 +176 +80 +176 +85 +185 +92 +198
+67 +152 +59 +138 +62 +143 +150 1 +302 1 ≤+90 ≤+194
— — — — +57 +134 +200 2 +302 2 ≤+90 ≤+194
1Max. flange temperature is +100°C / +212°F, if the PP Drop antenna is used. Max. flange temperature is +150°C / +302°F, if the PTFE
Drop antenna or Hygienic antenna are used.
2Do not use the PP Drop antenna. Max. flange temperature is +150°C / +302°F, if the PTFE Drop antenna or Hygienic antenna are used.
INFORMATION!
For applications for which EPL Gb equipment are necessary, the surface temperature of the
bottom of the transmitter can be as high as the flange temperature. We recommend that you put
insulation on these parts if the safety factor related to the minimum dust ignition temperature
does not agree with rules given in IEC 60079-14.

3 ELECTRICAL CONNECTIONS
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3.1 General notes
3.2 Terminal compartment
3.2.1 How to open the terminal compartment
• De-energize the circuit.
• After the time given in the table that follows, remove the cover stop 1.
iUse a 3 mm Allen wrench.
• Remove the terminal compartment cover 2.
WARNING!
• De-energize the circuit.
• Use the applicable cable glands for the cable entry openings in the housing (M20×1.5,
M25×1.5,
½ NPT or G ½ ). For the cable entry size, refer to the device nameplate. It is not
possible to have the G
½ cable entry option with Ex d- or Ex t-approved devices.
• If ambient temperature > +70 ° C / > +158 ° F, use heat-resistant cables, cable glands and cable
entry plugs certified for continuous operation above +80
° C / +176 ° F.
WARNING!
If dirt collects on the housing, clean the device with a damp cloth before you remove the terminal
compartment cover.
Figure 3-1: How to open the terminal compartment
1 Cover stop
2 Terminal compartment cover
WARNING!
Do not remove the terminal compartment cover while the electrical power is connected.

ELECTRICAL CONNECTIONS 3
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Time necessary to de-energize an Ex ia/d-, Ex d ia- or Ex ia tb-approved device
3.2.2 How to close the terminal compartment
Ex d / Ex t applications
• Attach the terminal compartment cover 2. Turn the terminal compartment cover carefully to
prevent damage to the thread and the gasket.
• Make sure that the terminal compartment cover is tight.
• Use a 3 mm Allen wrench to attach the cover stop 1.
• Make sure that the cover stop 1screw is tight.
3.3 Terminal tightening capacity
The terminal tightening capacity for current output terminals 1 and 2 is:
Temperature class Time to de-energize an Ex ia/d-, Ex d ia- or Ex ia tb-
approved device
[minutes]
T6 20
T5 10
Others Not necessary
WARNING!
If dirt collects on the terminal compartment gasket, clean it before you attach the terminal
compartment cover.
DANGER!
Ex d applications
Ex d applicationsEx d applications
Ex d applications
Make sure that the terminal compartment is correctly sealed. An explosion can cause death or
injury to personnel and/or damage to equipment. Obey the instructions that follow:
Type of wire Terminal tightening capacity
[mm²][AWG]
Rigid 411
Flexible 2.5 13

3 ELECTRICAL CONNECTIONS
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3.4 Equipotential bonding system
Connect the device to the equipotential bonding system for the hazardous location.
You can use 2 terminals to connect the device to the equipotential bonding system:
•a ground connection in the terminal compartment and
•an external ground terminal immediately below the signal converter
Makes sure that the electrical connections agree with the applicable regulations (IEC 60079-14).
Use the ground terminal in the terminal compartment to connect all electrical cable shields to
ground.
Ground all remaining electrical wires in the hazardous location or make sure that they have good
insulation. Refer also to the sections that follow in this chapter.
Ex ia-approved devices
The device electronics are isolated with a rating of 500 V
RMS
.
Ex ia/d-, Ex d ia- or Ex ia tb-approved devices
The device does not agree with the 500 V
RMS
dielectric strength requirement. Obey all the
instructions given in the "Electrical connections" chapter.
3.5 Ex ia equipment
3.5.1 How to connect the electrical cables
Refer to the handbook for data about the device terminals.
Cable entries are supplied on customer demand. If you supply the cable entries, this part must
have a degree of ingress protection IP≥6X (IEC 60529). We recommend that you use a part that
has a degree of ingress protection IP≥66. Make sure that the cable gland is sealed.
Obey the instructions that follow:
• Electrical wires must agree with applicable standards (e.g. IEC 60079-14).
• Use the electrical connection procedure in the Handbook.
• Put the electrical wires down, set them in position, and safely attach them to prevent damage.
The electrical wires must also be a sufficient distance from hot surfaces.
• Make sure that unused electrical wires are safely connected to the ground potential of the
hazardous area. If this is not possible, make sure that each of the unused electrical wires are
safely isolated (other electrical wires, ground etc.) and rated for a test voltage ≥500 V
RMS
.
• If it is necessary, make sure the electrical wire insulation gives good protection from
corrosion.
• Connect only to separate certified, intrinsically-safe circuits. Make sure that the electrical
circuit characteristics are not more than the values that follow.

ELECTRICAL CONNECTIONS 3
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3.5.2 Maximum intrinsically-safe values for the electrical circuit
Level transmitter with the 4...20 mA output option (output terminal 1 or 2)
•U
i
=30 V
•I
i
=300 mA
•P
i
=1 W
•C
i
=16 nF
•L
i
=29 µH
3.5.3 Supply voltage
Level transmitter with the 4...20 mA output option
3.5.4 Electrical schematic
INFORMATION!
The optional second output is galvanically isolated from the main power supply, output 1 and
parts of the device that are grounded.
Current output terminal Minimum voltage at output
terminal [VDC]
Maximum voltage at output
terminal [VDC]
1 (U
S1
)14 1 30 1
2 (U
S2
) 2 10 1 30 1
1Minimum voltage at output terminal for a current output of 22 mA
2Optional. Use a second power supply. This power supply energizes current output terminal 2 only.
Figure 3-2: Electrical schematic for Ex i-approved equipment with the 4...20 mA output option
1 Intrinsically-safe power supply (use a second power supply for optional terminal 2 if the device has two 4...20 mA out-
puts)
2 Non-Ex zone
3 Ex zone
4 Resistor for HART®communication
5 Grounding wire –if the electrical wire is shielded (braided wire etc.)
INFORMATION!
For applications where EPL Gb is necessary, you must also connect the device to an intrinsically-
safe circuit with protection concept "ib". If the device is connected to an intrinsically-safe circuit
with protection concept "ia", the device operates with a higher level of safety.

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3.6 Ex ia/d, Ex d ia and Ex ia tb equipment
3.6.1 General notes
Ex ia/d-, Ex d ia- and Ex ia tb-approved equipment have two separate compartments. The
electronics in the electronics block compartment are Ex ia-approved and the terminals
compartment is Ex d / Ex t-approved.
3.6.2 How to connect the electrical cables
Cable entries are supplied on customer demand. If you supply the cable entries, this part must
have a degree of ingress protection IP≥6X (IEC 60529). We recommend that you use a part that
has a degree of ingress protection IP≥66. Make sure that the cable gland is sealed.
Terminal compartment
•If you connect electrical wires to the terminals in the flameproof terminal compartment, use
approved flameproof cable glands (M20×1.5, M25×1.5 or ½NPT). The cable glands must have
a test certificate that agrees with IEC 60079-1. Obey the instructions given on the test
certificates. Make sure that that the tightening capacity of the cable entry is applicable to the
diameter of the electrical wire.
Figure 3-3: Compartments in Ex ia/d-, Ex d ia- and Ex ia tb-approved equipment
1 Electronics block (Ex ia) compartment
2 Terminal (Ex d / Ex t) compartment
INFORMATION!
If you must open the electronics block compartment and remove the electronics blocks for
servicing, it is not necessary to disconnect the wires from the Ex d / Ex t terminal.
INFORMATION!
The flamepath dimensions are better than the values specified in the International Standard
IEC 60079-1. For more data, speak to your supplier.
WARNING!
Use only Ex d-approved cable entries and plugs for Ex d applications. Use only Ex t-approved
cable entries and plugs for Ex t applications.
Do not remove more than 6 mm / 0.2
¨ of insulation from the wire.

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•If you use conduits to connect electrical wires to the terminals in the flameproof terminal
compartment, obey the instructions that follow. Make sure that the conduits are correctly
attached and the flameproof compartment is sealed. The flameproof joint must have a
minimum thread length of 8 mm / 0.32¨. The conduits must have a test certificate that agrees
with IEC 60079-1. Use conduit stopping boxes that agree with precautions given in the test
certificate and data in standards related to the installation of the conduit.
•If you connect electrical wires to the terminals in the dustproof terminal compartment, use
approved flameproof cable glands (M20×1.5, M25×1.5 or ½NPT). The cable glands must have
a test certificate that agrees with IEC 60079-31. Obey the instructions given on the test
certificates. Make sure that that the tightening capacity of the cable entry is applicable to
diameter of the electrical wire.
Obey instructions that follow:
•The electrical wiring must agree with the applicable standards (e.g. IEC 60079-14).
•Put the electrical wires down, set them in position, and safely attach them to prevent
damage. The electrical wires must also be a sufficient distance from hot surfaces.
•If it is necessary, make sure that the electrical wire insulation gives good protection from
corrosion.
•Make sure that the device is connected to a PELV (protective extra-low voltage) circuit.
•Make sure that electrical wires for the converter are isolated from the ground of the
hazardous area. This data is also applicable to the equipotential bonding conductors (PE).
•Make sure that unused electrical wires and shields are safely connected to the ground
potential of the hazardous area. If this is not possible, make sure that each of the unused
electrical wires are safely isolated (other electrical wires, ground etc.) and rated for a test
voltage ≥1500 V
RMS
.
Load resistor
• Connect the load resistor to the positive terminal of the power supply.
• Ground the negative connection.
• If the load resistor has to be connected to the negative terminal, the loop resistance must not
be more than 250 ohms.
3.6.3 Supply voltage
CAUTION!
Do not ground the positive connection.
Current output terminal Minimum voltage at output
terminal [VDC]
Maximum voltage at output
terminal [VDC]
1 (U
S1
)20 1 36 1
2 (U
S2
) 2 10 1 30 1
1Minimum voltage at output terminal for a current output of 22 mA
2Optional. Use a second power supply. This power supply energizes current output terminal 2 only.

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3.6.4 Electrical schematic
CAUTION!
Make sure that you connect the load resistor to the positive side.
Figure 3-4: Electrical schematic for Ex ia/d-, Ex d ia- and Ex ia tb-approved equipment (with galvanic isolation)
Figure 3-5: Electrical schematic for Ex ia/d-, Ex d ia- and Ex ia tb-approved equipment (without galvanic isolation)
1 Galvanically-isolated power supply (use a second power supply for optional terminal 2)
2 Power supply (use a second power supply for optional terminal 2)
3 Resistor for HART®communication
4 Non-Ex zone
5 Ex zone
6 Grounding wire –if the electrical wire is shielded (braided wire etc.)
7 |U| < 5 V