Danfoss Industrial Refrigeration systems in Potentially Explosive Atmospheres (Hazards area) ATEX 94/9/EC Directive [ATmosphères EXplosives] User guide

Danfoss Industrial Refrigeration systems in Potentially Explosive Atmospheres (Hazards area) ATEX 94/9/EC Directive [ATmosphères EXplosives] User guide
MAKING MODERN LIVING POSSIBLE
Application guide
Industrial Refrigeration systems in
Potentially Explosive Atmospheres
(Hazardous area) ATEX 94/9/EC Directive
[ATmosphères EXplosives]
www.danfoss.com/ir
Application guide
Industrial Refrigeration systems in Potentially Explosive Atmospheres (Hazardous area)
Contents
Page
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Application area for ATEX and Harmonised Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Scope of ATEX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Non-electrically equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Electrical equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Intrinsic safety protection method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Encapsulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Other requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
General zone classification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Zone classification principle of a refrigeration system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Guideline – zone classification of refrigeration systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Zone classification, general . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Zone classification for refrigeration systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Equipment group and zones . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Requirements for refrigeration components in countries outside Europe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
USA & Canada . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Other countries (China, Japan, Brazil, …..) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Danfoss solenoid coils, pressure controls and gas detectors suitable for use in
installations located in potentially explosive atmospheres . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Manufacturer’s declaration for potentially explosive atmosphere . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Declaration of conformity in accordance with ATEX 94/9 EC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Annex I:
Gas Groups and Temperature Classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Protection methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Annex II:
Classification of Danfoss Industrial Refrigeration products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Annex III:
Valves for HC-refrigerants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Annex IV:
Technical data for ICS3E . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Technical data for PMFHE or PMFLE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Technical data for SV3E . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Technical data for CVP-HPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Technical data for CVCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Technical data for EVME . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
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DKRCI.PA.000.A3.02 / 520H1296
© Danfoss A/S (AC-SMC/MWA), 09 - 2011
Application guide
Industrial Refrigeration systems in Potentially Explosive Atmospheres (Hazardous area)
Introduction
Industrial refrigeration components are mainly
used in ammonia refrigeration systems, but some
components are used in related applications,
where locations are classified as hazardous areas.
Danfoss has over a number of years supplied
components to this business area, particularly in
Europe. However, due to new, more restrictive
regulations, refrigeration components and
refrigeration systems have to fulfil requirements
for potentially explosive atmospheres, as
specified in the ATEX directive. PRS systems
(Process Refrigeration Systems) are typically
classified as hazardous areas, where the ATEX
requirements also have to be fulfilled.
The ATEX 94/9/EC directive is one of the “new”
European directives. The ATEX directive specifies
the requirements for equipment intended for
use in potentially explosive atmospheres. ATEX
is derived from the French term “ATmosphères
EXplosives”.
The ATEX directive replaces the previous EC
directive 76/117/EC which only included electrical
equipment, whereas ATEX includes both electrical
and non-electrical equipment.
The ATEX directive became mandatory from
1st July 2003 in all EU and EFTA member states.
Fig. 1 - EU and EFTA Member states
PED
Pressure Equipment
Directive
ATEX
Potentially explosive
atmosphere
EMC
Electro Magnetic
Compatibility
LVD
Low Voltage
Directive
MD
Machinery
Directive
Fig. 2 - EC directives
Application area for ATEX
and Harmonised Standards
© Danfoss A/S (AC-SMC/MWA), 09 - 2011
The ATEX as well as the harmonised technical
standards state requirements for:
Design of equipment / manufacture of
equipment / testing of equipment
Compliance with the ATEX directive ensures
free movement of goods / equipment
between all EU-member states and it also
ensures that the equipment can be put into
service, if there are no particular requirements
for the country of destination.
Important! - The zone classification for the
country of destination of a final refrigeration
system has to be approved by local authorities.
If local authorities require higher classification
than the actual equipment is approved for, the
system must not be used.
Installation and start up.
DKRCI.PA.000.A3.02 / 520H1296
ATEX is just one of a number of EC
directives refrigeration equipment
manufacturers have to comply
with, before their equipment
can be “placed on the market”
in the member states. Other
relevant directives for refrigeration
equipment are PED-Pressure
Equipment Directive, EMC Electro
Magnetic Compatibility, MDMachinery Directive and LVD-Low
Voltage Directive. The Directives
are “law” in the member states,
and only equipment fulfiling the
requirements must be CE marked
and “placed on the market”.
The ATEX directive does not state requirements for:
Operation – When the equipment is
operating at the end-users facility, national
laws become effective.
Degree of
protection
Very High
High
Normal
Protection
Two independent
protection measures or
safe if two errors occur
independently
Safe in normal
operation and in
anticipated case of
commonly occurring
errors
Safe in normal
operation
Category
Category 1
Category 2
Category 3
Fig. 3 - ATEX categories / degree of protection
3
Application guide
Industrial Refrigeration systems in Potentially Explosive Atmospheres (Hazardous area)
Scope of ATEX
Included in the ATEX Directive: Mining and non-mining equipment.
Explosive atmospheres caused by gas and
dust.
Electrical and non-electrical equipment.
Equipment (machines, devices, built-in
instruments or mobile devices).
Security systems (equipment which can stop /
limit explosions).
Components (parts without any independent
function).
Security control and regulation devices
intended for use outside explosive areas but
which secure the equipment in the hazardous
areas .
Non-mining equipment for potential explosive
atmospheres; classified as:
Equipment Group II.
– Category 1
– Category 2
– Category 3
The requirements in the categories depend on
the type of equipment.
Simple mechanical components like valves,
filters, check valves, etc. do normally not
contain any potential ignition source, and are
therefore not covered by the ATEX-directive.
Manufacturers of this kind of equipment,
must nevertheless carry out and keep a
Non electrical valve without
potential ignition source
Zone
–
–
–
–
Stop valves
Filters
Check valves
Etc.
Category 1
(Zone 0)
Category 2
(Zone 1)
Not covered by the scope of
ATEX Directive 94/9/CE
Category 3
(Zone 2)
Not included in the ATEX Directive: Medical equipment for hospital environments.
Equipment and protection systems for use
in connection with explosive or unstable
chemicals.
Household appliances and equipment intended
for use in non-commercial surroundings.
Personal Protection Equipment directive
89/686/EC.
Tankers and mobile offshore units.
Means of transport except vehicles.
Equipment for mining industries and explosive
atmospheres caused by dust are not covered in
this application guide.
risk assessment report, to prove that the
equipment do not have an ignition source,
and are safe for the purpose.
Mechanical components with potential
ignition sources e.g. components containing
non conductive materials, are covered by the
ATEX-directive. These products have to fulfil all
requirements in the ATEX directive, and have
to be marked with the required marking.
Electrically operated components are covered
by the ATEX-directive, and have to fulfil all
requirements in the ATEX directive, and have
to be marked with the required marking.
Non electrical valve with
potential ignition source
Zone
– Not relevant for common
industrial refrigeration
components
Electrical operated valve
Zone
– Electronic components
– Solenoid coils
– Etc.
CE-Type approval
III + IV or V
CE-Type approval
III + IV or V
Documentation at
Notified Body (VIII partly)
CE-Type approval
III + IV or VII
Internal quality control
(VIII)
Internal quality control
(VIII)
Fig. 4 - ATEX-requirements
NOTE:
The letters I, II,….VIII in figure 4, specify the relevant ATEX 94/9/EC directive “modules” that need to be complied
with.
Explosion triangle
The explosion triangle (fig. 5) shows the principle
of explosion. All three elements must be present
before an explosion can take place.
Removing one of the elements eliminates all risk
of explosion.
In refrigeration, the consideration regarding the
risk of explosion is limited to the outside of the
system itself. Within the refrigeration system,
there is 100% concentrated refrigerant with no
oxygen present, consequently there is no risk of
explosion.
4
DKRCI.PA.000.A3.02 / 520H1296
Fig. 5 - The explosion triangle
© Danfoss A/S (AC-SMC/MWA), 09 - 2011
Application guide
Industrial Refrigeration systems in Potentially Explosive Atmospheres (Hazardous area)
Non-electrical equipment
The requirements for non-electrically equipment
in hazardous areas are new. The risk analysis of
non-electrical refrigeration equipment (valves
and similar components) has to focus on ignition
sources.
The requirements for this kind of equipment are
specified in:
EN 1127-1 Explosive atmospheres.
Explosion prevention and protection, Part 1.
Basic concepts and methodology.
EN 13463-1 Non-electrical equipment for
potentially explosive atmospheres, Part 1.
Basic methods and requirements.
EN 13463-6 Non-electrical equipment for
potentially explosive atmospheres, Part 6.
Protection by control of ignition.
Electrical equipment
The requirements for electrical equipment in
hazardous areas are not new. The requirements
specified in the ATEX directive are almost
identical with the previous legislation and are
much more demanding than the requirements
for non-electrical equipment.
Intrinsic safety protection method
Intrinsic safety is an explosion protection
technique ensuring there is insufficient energy
to cause the ignition of a surrounding explosive
atmosphere by an electrical spark or the heating
of components or circuitry.
EX-zone
Examples:
Non-conductive materials (e.g. plastic) are
not acceptable. Non-conductive material can
create “static electricity”.
Category 2: Magnesium content must be less
than 7.5%.
Hot surfaces.
All possible sources of ignition have to be
analysed and avoided.
Simple components like stop valves, filters etc.
without the above mentioned ignition sources,
are normally not covered within the scope of the
ATEX directive.
A number of different methods can be used to
protect electrical equipment. Detailed below
are two commonly used methods of electrical
protection. Further methods are described in
Annex I.
Due to power consumption restrictions, this
method is only suitable for equipment with low
power consumption and is commonly used for
measuring devices.
Non EX-zone
Fig. 6 - Intrinsic safety protection method
Encapsulation
Encapsulation is an explosion protection
technique where the electrical components are
fully encapsulated. This method is often used for
components with“higher” power consumption
e.g. solenoid coils. However, power consumption
is also a limiting factor with this method due
to the risk of “high” surface temperature of the
component.
© Danfoss A/S (AC-SMC/MWA), 09 - 2011
DKRCI.PA.000.A3.02 / 520H1296
Note:
Solenoid valves with these coils can have
relatively low MOPD.
5
Application guide
Industrial Refrigeration systems in Potentially Explosive Atmospheres (Hazardous area)
Marking
Components covered within the scope of the
ATEX directive have to be CE-marked, and
marked with the specific
- sign. The marking
depends on the actual type of equipment.
Specific marking
9999
II
2
Additional marking
G
EEX
CE-marking & registration
number of Notified Body
Equipment Category:
1 (zone 0)
2 (zone 1)
3 (zone 2)
T4
Gas Group:
IIA
IIB
IIC
Nature of atmosphere:
G Gas
D Dust
Documentation
IIC
Protection type:
o for oil immersion
p for pressurisation
q for powder filling
d for flameproof enclosure
e for increased safety
ia for intrinsic safety
ib for intrinsic safety
m for encapsulation
Equipment group:
I Mining
II Non-mining
Fig. 7 -
d
Temperature class:
T1 to T6
-marking
The required documentation depends on whether
the component has an ignition source or not.
All components covered within the scope of the
ATEX directive must be supplied with a CE
declaration of conformity.
Non-electrical equipment without any ignition
source, is not covered within the scope of the
ATEX directive, but has to be supplied with the
manufacturer’s declaration.
The manufacturer’s declaration must declare
that the equipment is suitable for the purpose,
and that it does not have any ignition sources.
The manufacturer also has the obligation to
document a safety risk assessment for the
equipment.
Use
in
Use in
Explosive
Explosive
atmosphere
atmosphere
no
ATEX requirements
requirements
NoNo
ATEX
yes
Manufacturer’s risk
Manufacturer’s
risk
assessment
assessment
Potential
Potential
ignition
source
ignition source
no
Manufacture's
Manufacture’s
declaration for
declaration
for
potentially explosive
potentially
explosive
atmosphere
atmosphere
See fig. 15
yes
ATEX
ATEX94/9
94/9 ECEC
applies
applies
Declaration
Declaration ofof
conformity inin
conformity
accordance
withATEX
accordance
with
ATEX
94/9EC
EC
94/9
See fig. 16
Fig. 8 - Documentation
Other requirements
The ATEX directive does not differentiate between
different refrigerant types and for manufacturers
of refrigerant valves, this is an important issue.
Refrigeration valves are normally designed for
use with specific refrigerant types or groups
of refrigerants. In PRS systems flammable
refrigerants like propylene are often used.
When propylene is compared to e.g. ammonia it
has many different material compatibility issues.
Refrigerant
(flammable)
Propane
Butane
Iso-butane
Propylene
Ethane
Neoprene / CR (cloroprene)
Used for standard
refrigeration valves
fair
satisfactory
fair
unsatisfactory
fair
It is therefore very important that material
compatibility is also evaluated.
The suitability of O-rings with the different
refrigerant types depends on the compatibility
judgement, and the actual type of sealing.
An O-ring with a judgement “fair”, is normally
suitable for all internal sealings, but not
necessarily for external sealings. It is important to
make sure that specific products are approved for
the actual refrigerant.
Nitrile / NBR
Flourcarbon
FPM (Viton) 1)
satisfactory
satisfactory
satisfactory
doubtful
satisfactory
satisfactory
satisfactory
satisfactory
satisfactory
satisfactory
Fig. 9 - Material compatibility (sealing material / O-rings)
1
) There are no FPM O-rings available for low temperature (below –40°C)
6
DKRCI.PA.000.A3.02 / 520H1296
© Danfoss A/S (AC-SMC/MWA), 09 - 2011
Application guide
Industrial Refrigeration systems in Potentially Explosive Atmospheres (Hazardous area)
General zone classification
Components for use in hazardous areas are
classified from Category 1 to Category 3.
Hazardous areas are classified in Zones; Zone 0
is the most restrictive and Zones 1 and 2 are less
restrictive.
The zone classification of final equipment is very
important. It is also important to acknowledge
that local authorities have to approve the
specified zone classification of the final
equipment. There is no standard available, where
an exact definition of zones are made.
Valves and similar equipment in refrigeration
systems located in hazardous areas classified for
zone 2, 1 or 0, have to fulfil the requirements in
ATEX directive (Directive 94/9/EC).
Guideline –
zone classification of
refrigeration systems
Equipment group and zones
Locations for “standard “refrigeration systems
with CFC, HCFC, HFC, Ammonia are “normally”
not classified as hazardous areas. Requirements
for ammonia are specifically mentioned in EN
378-2 (for information also see prEN 378-2).
Refrigeration systems located in hazardous
areas (e.g. in petro chemical plants) have to
fulfil requirements for “Potentially explosive
atmospheres” irrespective of the refrigerant.
Industrial refrigeration systems with HC
refrigerants (e.g. Propane, Butane, Propylene,
etc) are “normally” classified as hazardous areas.
Certain local authorities interpret the
requirements so that equipment located in a
machinery room for a HC refrigeration system
is classified as Zone 2 if only one compressor is
employed. If two compressors are present, and
one of these is under service (e.g. changing oil),
then it becomes Zone 1.
“Potentially explosive atmospheres” do not
occur inside a refrigeration system because
no oxygen is present. (Refrigeration systems
designed and maintained according to EN 378
fulfil this requirement).
“Potentially explosive atmospheres” can occur
outside a refrigeration system (in the location
of a refrigeration system).
Refrigeration systems in “Potentially explosive
atmospheres” can contain flammable or nonflammable refrigerants.
Zone 22
Zone
Zone 00
Zone
Zone 11
Zone
Zone
Zone 00
Zone classification, general
Fig. 10 - Zone-classification principle
For refrigerant systems with flammable
refrigerants, special consideration should be
given to:
– The tightness of the system.
– The correct equipment is being used e.g. sealing materials must be compatible with the refrigerant.
– The system is maintained correctly.
Zone classification for refrigeration systems
Refrigeration systems are classified in relevant
zones according to the risk for the location for a
particular refrigerant system.
A particular refrigeration system can be classified
in different zones, for different part of the system.
No requirements
Zone 2
Low risk
-
DKRCI.PA.000.A3.02 / 520H1296
High risk
Condenser
Evaporator
Fig. 11 - Zone-classification principle for a refrigeration system
Hazards area
No requirements
© Danfoss A/S (AC-SMC/MWA), 09 - 2011
-
Zone 0
Compressor
Equipment located in zone specified areas must
fulfil the following requirements:
Category 3 - approved equipment can be
installed in hazardous areas zone 2 and
outside zone categorised areas.
Category 2 - approved equipment can be
installed in hazardous areas zone 1, zone 2
and outside zone categorised areas.
Category 1 - approved equipment can be
installed in hazardous areas zone 2, zone 1,
zone 0 and outside zone categorised areas.
Zone 1
ATEX
Directive
Zone 2
Zone 1
Zone 0
Catagory
3
Equipment Catagory
group II
2
Catagory
1
Fig. 12 - Category relations
7
Application guide
Industrial Refrigeration systems in Potentially Explosive Atmospheres (Hazardous area)
Requirements for
refrigeration components
in countries outside Europe
USA & Canada
Mechanical components without any electrical
equipment generally do not need to be
approved.
Electrical components have to be approved
according to UL, Division 1 or 2. When the
electrical equipment is mounted on e.g. a valve,
the complete valve assembly has to be approved.
Other countries (China, Japan, Brazil, …..)
In particular electrical equipment has to be
type approved in several countries, and the
requirements are different (e.g. only available in
local language).
Approval cost is generally relatively high for
these products, depending of actual division and
product type.
Definition
Degree of
protection
Areas in which a gas/
oxygen mixture occurs
CONTINUOUSLY or for
extended periods.
Very High
Areas in which a gas/
oxygen mixture occurs
OCCASIONALLY.
High
Areas in which a gas/
oxygen mixture occurs
EXCEPTIONALLY and only
for short periods.
Normal
Protection
Two independent
protection measures or
safe if two errors occur
independently.
Safe in normal operation
and in anticipated case
of commonly occuring
errors.
Safe in normal operation.
Europe
USA &
Canada
Zone 0
Division 1
Zone 1
Zone 2
Division 2
Fig. 13 - Hazardous areas Europe / USA
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DKRCI.PA.000.A3.02 / 520H1296
© Danfoss A/S (AC-SMC/MWA), 09 - 2011
Application guide
Solenoid coils type BP
II 2 G EEx m II T4
The coils are suitable for use in installations located in potentially
explosive atmospheres.
l
l
l
l
ATEX Category 2 (Zone 1).
Grade of enclosure: IP 67.
Supplied with 3 m moulded-in 3-core cable.
16 W dc.
NOTE 1: The coil has reduced MOPD
(MOPD~8 bar depending of actual valve type).
NOTE 2: The supply must be secured against a too high power
consumption in case of a short circuit.
Category 2 – Zone1
Danfoss solenoid coils,
pressure controls and gas
detectors suitable for use
in installations located
in potentially explosive
atmospheres
Industrial Refrigeration systems in Potentially Explosive Atmospheres (Hazardous area)
Literature No.: DKACV.PD.600.A
II 3 G EEx nA II T3
The coils are suitable for use in installations located in potentially
explosive atmospheres.
l
l
l
ATEX Category 3 (Zone 2).
Grade of enclosure: IP 67.
Supplied with 1 m moulded-in 3-core cable or terminal. 1- 20
W dc & ac
NOTE: The supply must be secured against a too high power
consumption in case of a short circuit.
Literature No.: RD3JE
Category 3 – Zone 2
Solenoid coils type “refrigeration”
Pressure Control type MP 55E
l
l
l
l
ATEX Category 3 (Zone 2).
Grade of enclosure: IP 20.
Max working pressure PS = 17 bar.
ATEX design
o Gold contactors.
o Stainless steel bellow with restricted movement.
o Soldering connection.
NOTE: Contact loads - Must be used with reliable means of
limiting the voltage and current to prevent sparks between the
contact surfaces. This could be zener diodes or Ex barriers.
Category 3 – Zone 2
II 3 G EEx nL IIC T6
The differential pressure controls are suitable for use in
installations located in potentially explosive atmospheres.
Literature No.: RD5CB
Pressure Control type KPE
ATEX Category 3 (Zone 2).
Grade of enclosure: IP 30 or IP 40
l Max working pressure: KP 1E: PS = 8 bar.
KP 7E: PS = 32 bar.
l ATEX design
o Gold contactors.
o Stainless steel bellow with restricted movement.
o Soldering connection.
l
l
NOTE: Contact loads - Must be used with reliable means of
limiting the voltage and current to prevent sparks between the
contact surfaces. This could be zener diodes or Ex barriers.
Category 3 – Zone 2
II 3 G EEx nL IIC T6
The pressure controls are suitable for use in installations located
in potentially explosive atmospheres.
Literature No.: RD5AC
© Danfoss A/S (AC-SMC/MWA), 09 - 2011
DKRCI.PA.000.A3.02 / 520H1296
9
Application guide
Industrial Refrigeration systems in Potentially Explosive Atmospheres (Hazardous area)
Pressure Transmitter Type MBS 4201
II 1 G EEx ia IIC T4 – T6
The pressure transmitters are suitable for use in installations
located in potentially explosive atmospheres.
l
l
l
ATEX Category 1 (Zone 0).
Grade of enclosure: IP 65 / IP67.
Measuring range 0 - 600 bar.
NOTE: Must be used in conjunction with safety barriers - (see
DKACT.PD.P20y1.02).
Literature No.: DKACT.PD.P20.W
II 2 G EEx d IIB + H2 T3 –T6
The gas detectors are suitable for use in installations located in
potentially explosive atmospheres.
l
l
ATEX Category 2 (Zone 1).
Grade of enclosure: IP 65.
NOTE: Literature No.: RD7HA
Category 2 – Zone 1
Gas detector type GD
Category 1 – Zone 0
Danfoss solenoid coils,
pressure controls and gas
detectors suitable for use
in installations located
in potentially explosive
atmospheres
(continued)
RT- pressure and temperature controls
l
l
l
l
l
l
ATEX design
ATEX Category 2 (Zone 1)
Grade of enclosure IP 67
Gold contactors
Stainless steel bellow with restricted movement
Stainless steel frame (conductive)
NOTE: Contact loads - Must be used with reliable means of
limiting the voltage and current to prevent sparks between the
contact surfaces. This could be zener diodes or Ex barriers.
Category 2 – Zone 1
II 2 G EEx ia IIC T6
The RT- pressure and temperature controls are suitable for use in
installations located in potentially explosive atmospheres.
Literature No.: RD5BA
Accessories for Potentially
Explosive Atmospheres
l
l
LED indication
power supply
Safety barriers.
I.S Isolator, transmitter supply unit Safety barriers and I.S
Isolator.
Literature No.: DKACT.PD.P20.Y
LED indication
open-circuit/
short-circuit
Fig. 14
10
DKRCI.PA.000.A3.02 / 520H1296
© Danfoss A/S (AC-SMC/MWA), 09 - 2011
Application guide
Industrial Refrigeration systems in Potentially Explosive Atmospheres (Hazardous area)
Manufacturer’s declaration
for potentially explosive
atmospheres
Manufacturer’s Declaration
to the European Directive ATEX 94/9/CE
Group D
Component with special sealing material for HC-refrigerants ( Propane, Butane,
Iso-butane and Propylene)
and - can be mounted with electrically pilots / equipment
and - have no ignition sources
Main Valves (control valves)
Modulating liquid level regulators
Pilots for ICS Valves
Pilots for ICS Valves
ICS 3E
PMFLE
CVP-HPE
EVME
For the above listed valves a hazard analysis to the directive ATEX 94/9/EC has been carried
out with the following result:
•
•
•
This non-electrical equipment holds no potential ignition source at normal usage.
The listed valves are not covered by the scope of ATEX Directive 94/9/EC.
The valves my be used in the following EX range:
ƒ Category 2 (Zone 1) and Category 3 (Zone 2)
IMPORTANT:
The above-mentioned valves are not identically to standard refrigeration valves.
The valves are equipped with special o-rings compatible with the specified refrigerants.
The valves have a reduced temperature range.
Note 1:
Valves used for the above condition has to installed and maintained according to the
requirements in EN 378.
Note 2:
Electronic / Mechanical actuators / pilots used to operate the above-mentioned equipment,
has to undergo a separate conformity assessment.
Reference to standards and directives:
EN 13453-1
EN 13453-5
EN 378
ATEX 94/9/EC
14/04/2005
Danfoss Industrial Refrigeration A/S
Danfoss Industrial Refrigeration has a quality and environmental management system that is
certified in accordance with international standards ISO 9001 and ISO 14001.
Our products comply with the requirements of the Pressure Equipment Directive 97/23/EC and are approved by TÜV Nord (0045)
Fig. 15
Declaration of conformity
in accordance with
ATEX 94/9 EC
Fig. 16
© Danfoss A/S (AC-SMC/MWA), 09 - 2011
DKRCI.PA.000.A3.02 / 520H1296
11
Application guide
Industrial Refrigeration systems in Potentially Explosive Atmospheres (Hazardous area)
Annex I
Gas Groups and
Temperature Classes
Gas Group
A
II
B
C
Ignition temperature
[°C]
Acetone
540
Acetic acid
485
Ammonia
630
Ethane
515
Methylene chloride
556
Methane (CH4)
595
Carbon monoxide
605
Propane
470
n-Butane
365
n-Butyl
370
Hydrogen sulfide
270
n-Hexane
240
Acetaldehyde
140
Ethyl ether
170
Ethyl nitrite
90
Ethylene
425
Ethyl oxide
429 - 440
Acetylene (C2H2)
305
Carbon bisulphide (CS2)
102
Hydrogen (H2)
560
Gas
T1
×
×
×
×
×
×
×
×
T6
×
×
×
×
×
×
×
×
×
×
×
×
450
Max. allowed equipment surface temp. [°C]
Temperature Class
T2
T3
T4
T5
300
200
135
100
85
The ignition temperature of a fluid is the lowest temperature at which the fluid / vapour will be ignited. This temperature defines
the Temperature Class. The Temperature Class, defines the highest allowable surface temperature . E.g. Equipment used with
Butane must have a max. allowable surface temperature of 300°C (Temperature Class T2), this means that equipment with
Temperature Class T2 to T6 can be used.
Protection methods
Technique
Protection type
Ex
Overpressure
Symbol
EN
Standard
Typical application
p
EN50 016
Control rooms
Lowered in oil
o
EN50 015
Analysis
Powder filling
q
EN50 017
Instumentation
Encapsulaiton
m
EN50 028
Instrumentation
solenoid coils e.g.
Refined
mechanical
design
Increased safety
e
EN50 019
Engines, lighting,
junction boxes
Energy
limitation
Intrinsic safety
ia ib
EN50 020
Instrumentation
e.g. MBS Pressure
Transmitters
Encapsulation
Explosionflameproof
d
EN50 018
Engines / pumps
Special
Special
s
General requirements for all methods
EN50 014
Separation
12
DKRCI.PA.000.A3.02 / 520H1296
© Danfoss A/S (AC-SMC/MWA), 09 - 2011
Application guide
Industrial Refrigeration systems in Potentially Explosive Atmospheres (Hazardous area)
Annex II
A
B
C
D
E
F
Category 1 Zone 0
Category 2 Zone 1
Category 3 Zone 2
Component type
Outside catagory / zone
ATEX Equipment group II
Category 1 Zone 0
Hazardous area
Category 2 Zone 1
“Non-flammable”
Flammable refrigerants Comments
refrigerants
(Ammonia, CFC,HCFC,
(Propane, Butane,
HFC,CO2)
Iso-butane, Propylene,
ethane)
Category 3 Zone 2
Product groups - ATEX requirements
Outside catagory / zone
Group
Classification of Danfoss Industrial Refrigeration products
Components which can be used with all refrigerants
and - cannot be mounted with any electrically pilots / equipment
and - have no ignition sources
Stop Valves
SVA-HS, X1
X
X
X
X
X
X
Filters
FIA
X
X
X
X
X
X
Check Valves
NRVS
X
X
X
X
X
X
Check Valves
NRVA
X
X
X
X
X
X
Components which can be used with Ammonia, CO2, CFC, HCFC, HFC refrigerants
and - cannot be mounted with any electrically pilots / equipment
and - have no ignition sources
Stop Valves
SVA-ST
X
X
X
Regulating Valves
REG
X
X
X
Stop Check Valves
SCA
X
X
X
Check Valves
CHV
X
X
X
Float Valves
HFI
X
X
X
Float Valves
SV
X
X
X
Pilots for ICS Valves
CVP, CVPP
X
X
X
Safety Valves
SFA
X
X
X
Safety Valves
SFV
X
X
X
Safety Valves
BSV
X
X
X
Change Over Valves for Safety Valves DSV
X
X
X
Safety Valves
POV
X
X
X
Components which can be used with Ammonia, CO2, CFC, HCFC, HFC refrigerants
and - can be mounted with electrically pilots / equipment
and - have no ignition sources
Note: Only EX approved coils, if any coils are used
Main Valves (control valves)
ICS 1 ICS 3
X
X
X
Main Valves (control valves)
PM1 PM3 PML PMLX
X
X
X
Modulating liquid level regulators
PMFH
X
X
X
Pilots for ICS Valves
EVM
X
X
X
Electrically operated expansion valve AKVA
X
X
X
Solenoid Valves
EVRS
X
X
X
Solenoid Valves
EVRA
X
X
X
Components with special sealing material for use with HC-refrigerants
(Probane, Butane, Iso-butane and Propylene)
and - can be mounted with electrically pilots / equipment
and - have no ignition sources
Note: Only EX approved coils, if any coils are used
Main Valves (control valves)
ICS3E
X
X
X
Modulating liquid level regulators
PMFHE
X
X
X
Pilots for ICS Valves
CVP-HPE
X
X
X
Pilots for ICS Valves
CVCE
X
X
X
Pilots for ICS Valves
EVME
X
X
X
Components not to be used in hazardous areas
Components in this group has an ignition source
Motor Valves
ICM, ICAD 600/900
Motor Valves
MRV / MEV
Level controls
38E, AKS 38, AKS 41/41U
Electronic regulators
EKC 2.., EKC 3..
“Standard” solenoid coils
all
Pilots
CVQ, CVPM
Electrical components for use in hazardous areas
RT-Safety pressure control
RTE
X
X
X
X
X
X
RT-Differential pressure control
RTE
X
X
X
X
X
X
RT-Thermostats
RTE
X
X
X
X
X
X
KPE-Safety pressure control
KPE; Ex II 3 G EEx nL IIC T6
X
X
MP 55E-Differential pressure control
MP 55E; Ex II 3 G EEx nL IIC T6
X
X
MBS Pressure transmitter
MBS 42xx; Ex II 1 G EEx ia II T4 - T6
X
X
X
X
X
X
X
X
EX solenoid coils
BP; Ex II 2 G EEx m II T4
X
X
X
X
X
X
EX solenoid coils
“ “; Ex II 3 G EEx nA II T3
X
X
X
X
Gas detector
GD; Ex II 2 G EEx d IIB + H2 T3 –T6
X
X
X
X
X
X
-
© Danfoss A/S (AC-SMC/MWA), 09 - 2011
DKRCI.PA.000.A3.02 / 520H1296
Literature No.: RD5CB102
Literature No.: RD5AC103
Literature No.: DKACT.PD.P20.W1.02
Literature No.: DKACV.PD.600.A4.03
Literature No.: RD5AC103
Literature No.: RD5AC103
13
Application guide
Valves for HC-refrigerants
14
Industrial Refrigeration systems in Potentially Explosive Atmospheres (Hazardous area)
ICS pilot control
ICS3E
20 D-5
ICS3E
20 D-10
ICS3E
20 D-15
ICS3E
20 D-20
ICS3E
20 D-25
ICS3E
25 D-5
ICS3E
25 D-10
ICS3E
25 D-15
ICS3E
25 D-20
ICS3E
25 D-25
ICS3E
32 D
ICS3E
40 D
ICS3E
50 D
ICS3E
65 D
Code no.
027H1060
027H1061
027H1062
027H1063
027H1064
027H2175
027H2176
027H2177
027H2178
027H2179
027H3029
027H4038
027H5037
027H6038
PMFHE High pressure float valve
PMFHE
80-2
PMFHE
80-3
PMFHE
80-4
PMFHE
80-5
PMFHE
80-6
PMFHE
80-7
PMFHE
125
PMFHE
200
PMFHE
300
PMFHE
500
Code no.
027F4038
027F4039
027F4040
027F4041
027F4042
027F4043
027F4044
027F4045
027F4046
027F4047
SV3E Pilot float valve
SV3E
Code no.
027B0081
CVP-HPE Pressure control pilot
CVP-HPE 4 to 22 bar
CVP-HPE 4 to 28 bar
CVP-HPE -0,66 to 7 bar
Code no.
027B0083
027B0084
027B0085
CVCE Pressure control pilot
CVCE
–0.45 to 7 bar
Code no.
027B0086
EVME Solenoid pilot
EVME
Code no.
032F8029
DKRCI.PA.000.A3.02 / 520H1296
Annex III
PMFLE Low pressure float valve
PMFLE
80-1
PMFLE
80-2
PMFLE
80-3
PMFLE
80-4
PMFLE
80-5
PMFLE
80-6
PMFLE
80-7
PMFLE
125
PMFLE
200
Code no.
027F4048
027F4049
027F4050
027F4051
027F4052
027F4053
027F4054
027F4055
027F4056
© Danfoss A/S (AC-SMC/MWA), 09 - 2011
Application guide
Industrial Refrigeration systems in Potentially Explosive Atmospheres (Hazardous area)
Annex IV
ICS3E valves
Are servo operated valves which belong to the
ICV (Industrial Control Valve) family.
Are special valves which can be used with
Hydro Carbon refrigerants.
Have three pilot pressure connections.
Technical data
Refrigerants:
Applicable to HC refrigerants (e.g. Propane,
Butane, Propylene, …..)
Max. working pressure: 52 bar g (754 psig)
O-ring material:
Fluorocarbon (Viton) compound for low
temperature application
Marking:
The valve is marked with the name “ICS3E”.
All dimensions and performance data are
identical to the standard ICS (Literature no.:
PD.HS0.A)
Temperature range: –40/+120°C (–40/+248°F).
Material specification
O-ring*
O-ring*
O-ring*
O-ring*
© Danfoss A/S (AC-SMC/MWA), 09 - 2011
No.
Part
Material
EN
ASTM
JIS
1
Body
Low temperature steel
G20Mn5QT, EN 10213-3
LCC A352
SCPL1 G5151
2
Top cover
Low temperature steel
G20Mn5QT, EN 10213-3
LCC A352
SCPL1 G5151
3
Function module
(assembled)
A
Cylinder
Steel
B
Piston
Steel
C
Valve plate
PTFE
D
Spring
Steel
E
Cone
Steel
F
Intermediate plate
Steel
4
Gasket
Fibre, non-asbestos
5
Bolts
Stainless steel
A2-70, EN 1515-1
Grade B8 A320
A2-70, B 1054
6
Plug
Steel
7
Gasket
Aluminium
8
Manual operating
spindle
Steel
Steel
9
Plug
10
Gasket
Aluminium
*
O-ring
Flourocarbon (Viton)
DKRCI.PA.000.A3.02 / 520H1296
15
Application guide
PMFHE or PMFLE
valves
Industrial Refrigeration systems in Potentially Explosive Atmospheres (Hazardous area)
Are modulating servo-controlled main
expansion valves, controlled by pilot float
valve type SV3E.
Are special valves which can be used with
Hydro Carbon refrigerants.
Have one pilot pressure connection.
Temperature range: –40/+120°C (–40/+248°F).
Max. working pressure: 28 bar g (406 psig)
O-ring material:
Fluorocarbon (Viton) compound for low
temperature application
Marking:
The valve is marked with the name “PMFHE” or
“PMFLE”.
Technical data
Refrigerants:
Applicable to HC refrigerants (e.g. Propane,
Butane, Propylene, …..)
All dimensions and performance data are identical
to the standard PMFH or PMFL (Literature no.:
RD2CB).
Material specification
O-ring*
O-ring*
O-ring*
O-ring*
PMFHE
No.
16
PMFLE
Part
Material
2
Gasket between body
and flange
Non-metal
Non-asbestos
DIN/EN
ISO
ASTM
3
Bolts for flange
4
Flange PM 5 - 65
Stainless steel
A2-70
A2-70
Type 308
Steel
RSt. 37-2, 10025
Fe360 B, 630
6
Grade C, A 283
Plug
Steel
9SMn28
1651
Type 2
R683/9
1213
SAE J 403
10
Valve spindle
Steel
9SMn28
1651
Type 2
R683/9
1213
SAE J 403
12
Valve seat
Teflon [PTFE]
19
Valve body
Low temperature cast
iron (spherical)
EN-GJS-400-18-LT
EN-1693
20
Bottom cover
Low temperature cast
iron (spherical)
EN-GJS-400-18-LT
EN-1693
23
Spring
Steel
24
Servo piston
Cast iron
GG-25
Grade 250
Class 40B
30
Cover
Low temperature cast
iron (spherical)
EN-GJS-400-18-LT
EN-1693
31
Trottle cone
Steel
9SMn28
1651
Type 2
R683/9
1213
SAE J 403
32
Gasket between body
and bottom cover
Non-metal
Non-asbestos
34
Bolts for top and
bottom cover
Stainless steel
A2-70
A2-70
Type 308
41
Gasket
Non-metal
Non-asbestos
43
Spring
Steel
53
Spindle cap
Steel
9SMn28
1651
Type 2
R683/9
1213
SAE J 403
60
Setting / manual
operating spindle
Steel
9SMn28
1651
Type 2
R683/9
1213
SAE J 403
73
Pilot connection
Steel
9SMn28
1651
Type 2
R683/9
1213
SAE J 403
*
O-ring
Flourocarbon (Viton)
DKRCI.PA.000.A3.02 / 520H1296
© Danfoss A/S (AC-SMC/MWA), 09 - 2011
Application guide
SV3E valves
Industrial Refrigeration systems in Potentially Explosive Atmospheres (Hazardous area)
Can be used separately as a modulating liquid
level regulator in refrigerating, freezing and
air conditioning systems for ammonia or
fluorinated refrigerants. However, in most
cases, the SV3E is used as a float pilot valve for
the main expansion valve type PMFHE.
Are special valves which can be used with
Hydro Carbon refrigerants.
Technical data
Refrigerants:
Applicable to HC refrigerants (e.g. Propane,
Butane, Propylene, …..)
Temperature range: –40/+120°C (–40/+248°F).
Max. working pressure: 28 bar g (406 psig)
O-ring material:
Fluorocarbon (Viton) compound for low
temperature application
Marking:
The valve is marked with the name “SV3E”.
All dimensions and performance data are identical
to the standard SV (Literature no.: RD2BB).
Material specification
No.
© Danfoss A/S (AC-SMC/MWA), 09 - 2011
Part
Material
DIN / EN
1
Float housing
Stainless steel
Low temperature, steel
X5CrNi18-10, DIN 17440
P285QH, EN 10222-4
2
Float
Stainless steel
3
Split pin
Steel
4
Float arm
Stainless steel
5
Link
Steel
6
Pin
High density polymer
7
Valve housing
Steel
8
O-ring
Flourocarbon (Viton)
9
Float orifice
High density polymer
10
Manual regulation unit.
Throttle valve
Steel
11
Gasket
Non asbestos
12
Plug
Steel
13
O-ring
Flourocarbon (Viton)
14
Pilot connection
(spare part)
Steel
15
Orifice needle
Plastic
16
O-ring
Flourocarbon (Viton)
17
Screw
Steel
18
Gasket
Non asbestos
19
Pin
Steel
20
Cover
Low temperature, cast iron
(spherical)
EN-GJS-400-18-LT
EN 1563
21
Screw
Stainless steel
A2-70
22
Gasket
Non asbestos
23
Label
Cardboard
25
Screw
Steel
26
Spring washer
Steel
28
Sign
Aluminium
DKRCI.PA.000.A3.02 / 520H1296
17
Application guide
CVP-HPE valves
Industrial Refrigeration systems in Potentially Explosive Atmospheres (Hazardous area)
Are constant pressure pilot valves for high
pressure applications.
Are special valves which can be used with
Hydro Carbon refrigerants.
Technical data
Refrigerants:
Applicable to HC refrigerants (e.g. Propane,
Butane, Propylene, …..)
O-ring material:
Fluorocarbon (Viton) compound for low
temperature application
Marking:
The valve is marked with the name “CVP-HPE”.
All dimensions and performance data are identical
to the standard CVP (Literature no.: PD.HN0.A).
Temperature range: –40/+120°C (–40/+248°F).
Max. working pressure: 28 bar g (406 psig)
Material specification
18
No.
Part
Material
A1
O-ring
Flourocarbon (Viton)
A2
Seal
Non-asbestos
1
Protective cap
Steel
3
Seal
Non-asbestos
4
Nut
Stainless steel
10
Diaphragm
Stainless steel
11
Thrust pad
Stainless steel
12
Spring guide
Stainless steel
13
Flange
Steel
14
Orifice
Stainless steel
15
Base
Stainless steel
17
Valve body
Cast iron
18
Cover bolt
Steel
20
Setting spindle
Stainless steel
21
Screw (M6 × 10)
Steel
22
Cover gasket
Non-asbestos
24
Spring
Steel
28
Spring
Steel
DKRCI.PA.000.A3.02 / 520H1296
© Danfoss A/S (AC-SMC/MWA), 09 - 2011
Application guide
CVCE valves
Industrial Refrigeration systems in Potentially Explosive Atmospheres (Hazardous area)
Are pressure-operated pilot valves with an
external signal connection that can be used to
obtain an indication of the system reference
pressure.
Are special valves which can be used with
Hydro Carbon refrigerants.
Technical data
Refrigerants:
Applicable to HC refrigerants (e.g. Propane,
Butane, Propylene, …..)
Temperature range: –40/+120°C (–40/+248°F).
Max. working pressure: 28/17 bar (406/247 psig)
O-ring material:
Fluorocarbon (Viton) compound for low
temperature application
Marking:
The valve is marked with the name “CVCE”.
All dimensions and performance data are identical
to the standard CVC (Literature no.: PD.HN0.A).
Material specification
The maximum working pressure (MWP)
refers to the high-pressure side of the
valve (28 bar); the reference pressure
(17 bar) refers to the low-pressure side
of the system.
The reference pressure must be
connected to the low-pressure side of
the system.
O-ring*
O-ring*
No.
Part
Material
17
Valve body
Stainless steel
43
Seal
Aluminium
44
Blanking plug for pressure gauge connection
Stainless steel
81
Seal
Non-asbestos
82
O-ring
Flourocarbon (Viton)
103
Banjo fitting
Steel
104
O-ring
Flourocarbon (Viton)
105
Protective cap
Steel
106
O-ring
Cloroprene (Neoprene)
107
Signal connection
108
Pilot orifice
Stainless steel
109
Connector on banjo fitting 103
Steel
110
Diaphragm
Stainless steel
111
Spring
Steel
112
Setting spindle
Stainless steel
O-ring
Flourocarbon (Viton)
*
© Danfoss A/S (AC-SMC/MWA), 09 - 2011
DKRCI.PA.000.A3.02 / 520H1296
19
Application guide
EVME valves
Industrial Refrigeration systems in Potentially Explosive Atmospheres (Hazardous area)
Are pilot solenoid valves suitable for liquid,
suction and hot gas lines applications.
Are special valves which can be used with
Hydro Carbon refrigerants.
Technical data
Refrigerants:
Applicable to HC refrigerants (e.g. Propane,
Butane, Propylene, …..)
Temperature range: –40/+120°C (–40/+248°F).
O-ring material:
Fluorocarbon (Viton) compound for low
temperature application
Marking:
The valve is marked with the name “EVME”.
All dimensions and performance data are identical
to the standard EVM (Literature no.: PD.HN0.A).
Note: Solenoid coils must be EX approved.
Max. working pressure: 42 bar (609 psig).
Material specification
5
No.
20
Part
Material
2
Armature
Stainless steel
3
Armature tube
Stainless steel
4
Seal
Non-asbestos
5
O-ring
Flourocarbon (Viton)
6
Seal
Aluminium
7
Spacing ring
10
Valve body
Steel
11
Valve seat
Teflon (PTFE)
DKRCI.PA.000.A3.02 / 520H1296
© Danfoss A/S (AC-SMC/MWA), 09 - 2011
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