Bosch Rexroth H-4WEH...XE Series User manual

Operating instructions
RE 24751-XE-B/04.16
Replaces: 09.13
English
4/2 and 4/3 directional valves,
internally pilot-operated,
externally pilot-operated
(Area of application according to the explosion protection directive 2014/34/EU: II 2G)
Type H-4WEH...XE...

The data specified serves to describe the
product. If there is also information on the
use, itis only to be regarded as application
examples and proposals. Catalog information
does not constitute warranted properties.
Theinformation given does not release the
user from the obligation of own judgment and
verification. Our products are subject to a
natural process of wear and aging.
© This document, as well as the data,
specifications and other information set
forth in it, are the exclusive property of
Bosch Rexroth AG. It may not be reproduced or
given to third parties without its consent.
The cover shows an example configuration.
Theproduct supplied may therefore differ from
the figure shown.
The original operating instructions were
prepared in German.

RE 24751-XE-B/04.16, H-4WEH...XE..., Bosch Rexroth AG
3/52Contents
Contents
1 About this documentation 5
1.1 Validity of the documentation 5
1.2 Required and amending documentation 5
1.3 Representation of information 5
2 Safety instructions 7
2.1 General information on this chapter 7
2.2 Intended use 7
2.3 Improper use 8
2.4 Qualification of personnel 9
2.5 General safety instructions 10
2.6 Product-specific safety instructions 11
2.7 Notices on the valve use 13
2.8 Personal protective equipment 14
2.9 Obligations of the machine end-user 14
3 General information on damage to property and damage to product 15
4 Scope of delivery 16
5 Product information 16
5.1 Product identification 17
6 Transport and storage 22
6.1 Transporting the valve 22
6.2 Storing the hydraulic valve 23
7 Assembly 24
7.1 Unpacking 24
7.2 Changes to the surface protection of the valve 24
7.3 Installation conditions 24
7.4 Before the assembly 25
7.5 Required tools 25
7.6 Required accessories 25
7.7 Assembling the valve 26
8 Commissioning 34
9 Operation 37
9.1 General information 37
9.2 Operating the manual override (only relevant for type H-4WEH./.NXE.) 38
10 Maintenance and repair 39
10.1 Cleaning and care 39
10.2 Inspection and maintenance 39
10.3 Maintenance schedule 41
10.4 Repair 41
10.5 Rectifying external leakages 41
10.6 Spare parts 42
11 Disassembly and removal 43
12 Disposal 44
12.1 Environmental protection 44
12.2 Return to Bosch Rexroth AG 44
12.3 Packaging 44
12.4 Materials used 45

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12.5 Recycling 45
13 Extension and modification 45
14 Troubleshooting 46
14.1 How to proceed for troubleshooting 46
15 Technical data 47
16 Appendix 48
16.1 List of addresses 48
17 Declaration of conformity 49
18 Alphabetical index 50

About this documentation 5/52
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1 About this documentation
1.1 Validity of the documentation
This documentation applies to the following products:
•H-4WEH...XE...
This documentation is intended for assemblers, operators, service engineers, system
end-users, machine and system manufacturers.
This documentation contains important information on the safe and proper
assembly, transport, commissioning, operation, use, maintenance, disassembly and
simple troubleshooting of the product.
▶ Read this documentation thoroughly and in particular chapter2 "Safety
instructions" and chapter 3 "General information on damage to property and
damage to product" before working with the valve.
1.2 Required and amending documentation
▶ The product may not be commissioned until you have been provided with the
documentation marked with the book symbol and you have understood and
observed it.
Table 1: Required and amending documentation
Title Document number Document type
4/2 and 4/3 directional valves, internally
pilot-operated, externally pilot-operated
24751-XE Data sheet
General product information on
hydraulic products
07008 Data sheet
Subplates 45100 Data sheet
Declaration of conformity H-4WEH...XE... Document
Refer to operating
instructions
24751-XE-B
1.3 Representation of information
Uniform safety instructions, symbols, terms and abbreviations are used to ensure
quick and safe working with the product using this documentation. For a better
understanding, they are explained in the following sections.
1.3.1 Safety instructions
In this documentation, safety instructions are included in chapter2.6 "Product-
specific safety instructions" and in chapter3 "General information on damage
to property anddamage to product" and whenever a sequence of actions or
instructions is explained which bear the danger of personal injury or damage to
property. Thehazard avoidance measures described must be observed.

6/52 About this documentation
Bosch Rexroth AG, H-4WEH...XE..., RE 24751-XE-B/04.16
Safety instructions are structured as follows:
SIGNAL WORD
Type and source of danger!
Consequences in case of non-compliance
▶ Hazard avoidance measures
▶ <Enumeration>
•Warning sign: draws attention to the danger
•Signal word: identifies the degree of danger
•Type and source of danger: specifies the type and source of danger
•Consequences: describes the consequences in case of non-compliance
•Precaution: specifies how the danger can be prevented
Table 2: Risk classes according to ANSI Z535.6-2006
Warning sign, signal word Meaning
DANGER Indicates a dangerous situation which will cause death or
severe injury if not avoided.
WARNING Indicates a dangerous situation which may cause death or
severe injury if not avoided.
CAUTION Indicates a dangerous situation which may cause minor or
moderate (personal) injury if not avoided.
NOTICE Damage to property: The product or the environment could
be damaged.
1.3.2 Symbols
The following symbols indicate notices which are not safety-relevant but increase the
comprehensibility of the documentation.
Table 3: Meaning of the symbols
Symbol Meaning
If this information is not observed, the product cannot be used and/or
operated optimally.
▶ Individual, independent action
1.
2.
3.
Numbered instruction:
The numbers indicate that the actions must be carried out one after
theother.
1.3.3 Abbreviations
The following abbreviations are used in this documentation:
Table 4: Abbreviations
Abbreviation Meaning
ATEX EU Explosion Protection Directive (Atmosphère explosible)
EN European Standard
ISO International Organization for Standardization

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Abbreviation Meaning
IEC International Electrotechnical Commission
RE Rexroth document
IP Ingress protection rating
A, B Hydraulic connections (actuator)
T Hydraulic connection (tank)
P Hydraulic connection (pump)
X, Y Hydraulic connection (pilot oil)
ANSI American National Standards Institute
2 Safety instructions
2.1 General information on this chapter
The product has been manufactured according to the generally accepted codes of
practice. However, there is still the danger of personal injury and damage to property
if you do not observe this chapter and the safety instructions in this documentation.
▶ Read this documentation completely and thoroughly before working with
theproduct.
▶ Keep this documentation in a location where it is accessible to all users at
alltimes.
▶ Always include the required documentation when you pass the product on to
third parties.
2.2 Intended use
The product is a hydraulic component.
You may use the product as follows:
•as a pilot-operated valve with solenoid actuation for intended use in explosive
atmospheres.
The product is only intended for professional use and not for private use.
Intended use includes having read and understood this documentation completely,
especially chapter 2 "Safety instructions".
The valve is designed and constructed for the control of oil flows. It complies with
the requirements of the EU explosion protection directive 2014/34/EU. According
to directive 2014/34/EU, the device group, category and temperature class to which
the valve corresponds are indicated in the "Area of application" section of the
datasheet.

8/52 Safety instructions
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For information on the device group, category and temperature class according to
the explosion protection directive 2014/34/EU, please refer to "Data sheet 24751-XE"
under "Information on explosion protection" and to the name plate of the valve.
The valve may only be operated in a technically perfect condition and used as
described in these operating instructions. The connection conditions, application
conditions and performance data defined in these operating instructions must not
be changed.
If you intend to use the valve with other connection, application or performance
data than those defined by Bosch Rexroth AG in these operating instructions, please
contact Bosch Rexroth AG beforehand. The valve must not be used with other
connection, application and performance data than those defined in these operating
instructions without the written approval by Bosch Rexroth AG.
2.3 Improper use
Any use deviating from the intended use is improper and thus not admissible.
The installation or use of inappropriate products in safety-relevant applications
could result in unintended operating states during use which in turn could cause
personal injuries and/or damage to property. Therefore, please only use a product
for safety-relevant applications if this use is expressly specified and permitted in
the documentation of the product. For example, in explosion-protected areas or in
safety-related control components (functional safety).
Improper use of the product includes:
•Faulty assembly
•Incorrect transport
•Lack of cleanliness during storage and assembly
•Faulty installation
•Use of inappropriate/non-admissible hydraulic fluids
•Non-compliance with the specified performance limits
Changes and/or modification at the valve are not admissible, see chapter 13
"Extension and modification".
Bosch Rexroth AG does not assume any liability for damage caused by improper use.
The user assumes all risks involved with improper use.

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2.4 Qualification of personnel
The activities described in this documentation require basic knowledge of
mechanics, electrics, hydraulics, pneumatics as well as knowledge of the appropriate
technical terms. For transporting and handling the product, additional knowledge
of how to handle lifting gear and the necessary attachment devices is required.
Inorder to ensure safe use, these activities may only be carried out by an expert in
therespective field or an instructed person under the direction and supervision of
an expert.
Experts are those who are able to recognize potential dangers and apply the
appropriate safety measures due to their professional training, knowledge and
experience, as well as their understanding of the relevant conditions pertaining
to the work to be undertaken. An expert must observe the relevant specific
professional rules and have the necessary expert knowledge.
Expert knowledge means for example for hydraulic products:
•reading and completely understanding hydraulic schemes,
•in particular, completely understanding the correlations regarding the safety
equipment and
•having knowledge of the function and set-up of hydraulic components.
The personnel must have the following additional qualifications to the extent
required to fulfill their tasks:
•Understanding of the general principles of explosion protection, protection classes
and device labelling
•Understanding of those aspects of device design which influence the protection
concept
•Understanding of the contents of certificates and of the relevant parts of this
standard
•General understanding of the testing, maintenance and repair requirements of
IEC60079-17
•Familiarity with the special methods which are to be applied during the selection
and installation of devices to which this standard refers
•Understanding of the additional importance of work permit systems and safe
electrical separation regarding explosion protection
Bosch Rexroth offers measures supporting training in specific fields. You can find
an overview of the training contents on the Internet at:
http://www.boschrexroth.de/didactic
Qualification of personnel
for the installation and
commissioning of valves in
explosive areas

10/52 Safety instructions
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2.5 General safety instructions
•Observe the valid regulations on accident prevention and environmental protection.
•Observe the safety regulations and provisions of the country in which the product
is used/applied.
•Exclusively use Rexroth products in technically perfect condition.
•Observe all notices on the product.
•Persons assembling, operating, disassembling or maintaining Rexroth products
must not be under the influence of alcohol, other drugs or medication influencing
the ability to react.
•Only use original Rexroth accessories and spare parts in order to exclude any
hazard to persons due to unsuitable spare parts.
•Comply with the technical data and environmental conditions specified in the
product documentation.
•The installation or use of inappropriate products in safety-relevant applications
could result in unintended operating states during use which in turn could cause
personal injuries and/or damage to property. Therefore, only use a product for
safety-relevant applications if this use is expressly specified and permitted in the
documentation of the product, e.g. in explosion protection zones or in safety-
related parts of control systems (functional safety).
•Do not commission the product until you can be sure that the end product (for
example a machine or system) where the Rexroth product is installed complies
with the country-specific provisions, safety regulations and standards of the
application.

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2.6 Product-specific safety instructions
The following safety instructions apply to chapters 6 to 14.
WARNING
Explosion hazard due to explosive atmosphere during assembly!
During assembly, there must not be an explosive atmosphere. During work at the
valve, this condition could trigger an ignition which may lead to an explosion.
▶ Before working with the valve, ensure that no explosive atmosphere may occur
during the work.
Easily inflammable hydraulic fluid!
In connection with an explosive atmosphere or other hot heat sources, leaking
hydraulic fluid mist due to defective or incompletely assembled valves and their
connections may lead to explosions.
▶ Only use the valve in the intended explosion protection area.
▶ The ignition temperature of the hydraulic fluid used must be 50 K higher than
the maximum surface temperature.
Exceedance of the maximum temperatures!
Use of the valve outside the approved temperature ranges may lead to functional
failures like e.g. overheating of the valve solenoid. This means that the explosion
protection is no longer ensured.
▶ Only use the valve within the intended environmental and hydraulic fluid
temperature range.
Hot surface at the valve solenoid!
Risk of burning!
▶ Provide for a suitable touch guard.
▶ During operation, only touch the valve solenoid using heat-protective gloves.
Allow the valve solenoid to cool down to room temperature before touching it
directly with your hands during maintenance work.
Pressurized system parts and leaking hydraulic fluid!
When working at hydraulic systems with stored pressure energy (accumulators
or cylinders working under gravity), the valve may even be pressurized after the
pressure supply has been switched off. During assembly and disassembly work,
the valve or parts may fly around and cause personal injuries and/or damage to
property. There is moreover the danger of serious injury caused by a powerful
leaking hydraulic fluid jet.
▶ Before working at the valve, ensure that the hydraulic system is depressurized
and the electrical control is de-energized.
▶ Completely unload the pressure at machines and systems before working at
thevalve.

12/52 Safety instructions
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WARNING
Non-compliance with functional safety!
The valve controls movements in machines or systems. In case of mechanical and
electric faults, e.g. failure of the energy supply, persons may be caught by the
system, kicked away or bruised.
▶ When setting up your circuit, observe functional safety e.g. according to
ENISO13849.
Penetrating water and humidity!
In case of use in humid or wet environments, water or humidity may penetrate at
electrical connections or the valve electronics. This case may lead to malfunctions
at the valve and to unexpected movements in the hydraulic system which may result
in personal injury and damage to property.
▶ Only use the valve within the intended IP protection class or lower.
▶ Ensure before the assembly that all seals and caps of the plug-in connections
are tight and intact.
CAUTION
Contaminated hydraulic fluid!
Contamination in the hydraulic fluid may cause functional failures e.g. jamming or
blocking of nozzles of the valve. In the worst case, this may result in unexpected
system movements and thus constitute a risk of injury for persons.
▶ Ensure adequate hydraulic fluid cleanliness according to the cleanliness classes
of the valve over the entire operating range.
Leakage in case of incorrect working temperatures!
Use of the valve outside the approved temperature ranges may lead to permanent
leakage at the valves. Thus, hydraulic fluid in the form of a leaking hydraulic fluid jet
may injure persons, lead to damage to property and endanger the environment.
▶ Only use the valve within the intended environmental and hydraulic fluid
temperature range.
▶ In case of leakage, immediately exchange damaged seal rings or the valve.
Corrosion!
The valve described has surface protection (see Data sheet "24751-XE"). If the
valve is used in a damp environment, the valve and the valve mounting screws may
corrode, which may reduce the preload force of the screw connection. To prevent
the valve from becoming loose and causing a risk of injury:
▶ Exchange valves with corrosion damage at an early stage.
▶ Check the surface protection at the valve and the valve mounting screws at
regular intervals.

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Contact with salt water leads to increased corrosion at the valve. This may
chemically corrode and damage individual components of the valve. So take
suitable corrosion protection measures.
2.7 Notices on the valve use
Observe the following information during project planning:
▶ Special application conditions for safe use include that in case of valves with two
solenoids, maximally one solenoid is operated at a time in all operating states.
The simultaneous operation of both solenoids leads to malfunctions, excessive
heating and will result in loss of explosion protection.
▶ Be aware of possible pressure intensification if the valve is connected to the
chamber on the piston rod side of a differential cylinder. If the outflow of the
hydraulic fluid from this chamber is obstructed, pressure on the cylinder may
result in a pressure intensification that may damage cylinder chamber, supply
line, andvalve.
▶ To ensure proper functioning, the valve must be bled. It must be ensured that the
values for the minimum pilot pressure specified in "Data sheet 24751-XE, Technical
data, hydraulic" are complied with.
▶ Pressure peaks in the joint return line of more than one valve may cause
unintended movements of the control spool and thus unintended switching
processes. This particularly holds true when valves with detent are used. It is
recommended to use separate return lines.
▶ Ports P, A, B and T as well as the pilot oil ports X and Y are clearly assigned
according to their function and must not be exchanged or closed. The flow is only
admissible in the direction of arrow specified in "Data sheet 24751-XE".
▶ Switching off the valve solenoid results in a voltage peak due to the inductive
effect. The valve solenoid already contains an interference protection circuit
dampening this voltage peak. However, additional external switching measures
have to be taken, if required, in order to avoid connected electric circuits being
influenced by the residual voltage peak. The values for the residual voltage peak
depend on the valve solenoid used, see the "Data sheet 24751-XE".

14/52 Safety instructions
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2.8 Personal protective equipment
The machine end-user must provide the personal protective equipment (such as
gloves, working shoes, safety goggles, working clothes, etc...).
2.9 Obligations of the machine end-user
The machine end-user is obliged to check in the order confirmation whether the
supplied valve complies with the required category and the corresponding zone.
The machine end-user of the Bosch Rexroth valve is responsible that
•the valve is only used according to the intended use as defined in these operating
instructions.
•the valve is only stored, operated and maintained according to the technical data,
operating and environmental conditions indicated in "Data sheet 24751-XE", in
particular that the limit values indicated in "Data sheet 24751-XE" are not exceeded.
•the applicable provisions, regulations and directives on explosion protection are
complied with.
•the operating personnel are instructed at regular intervals.
•a danger zone is marked, if required.
•the safety measures for the specific area of application of the valve are
complied with.

General information on damage to property anddamage to product 15/52
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3 General information on damage to
property anddamage to product
The warranty only applies to the delivered configuration.
•The claim to warranty expires if the product is incorrectly assembled,
commissioned and operated, not used as intended and/or handled improperly.
•The following safety instructions apply to chapters 6 to 14.
NOTICE
Inadmissible mechanical load!
Impact or shock forces on the valve may damage or even destroy it.
▶ Never use the valve as a handle or a step. Do not place/put any objects on top
ofit.
Dirt and foreign particles in the valve!
Penetrating dirt and foreign particles in the valve lead to wear and malfunctions.
Safe function of the valve is therefore no longer ensured.
▶ During installation, ensure utmost cleanliness in order to prevent foreign
particles such as welding beads or metal chips from getting into the hydraulic
lines.
▶ Before commissioning, ensure that all hydraulic connections are tight and
that all seals and caps of the plug-in connections are correctly installed and
undamaged.
▶ Do not use linting cleaning fabric for cleaning.
▶ Ensure that no cleaning agents are able to penetrate the hydraulic system.
Hydraulic fluid harmful to the environment!
Leaking hydraulic fluid leads to environmental pollution.
▶ Immediately remedy possible leakage.
▶ Dispose of the hydraulic fluid in accordance with the currently applicable
national regulations in your country.

16/52 Scope of delivery
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4 Scope of delivery
The scope of delivery includes:
•Pilot-operated directional valve
type H-4WEH...XE...
•Operating instructions including declaration of conformity
▶ Check the scope of delivery for completeness.
▶ Check the scope of delivery for possible transport damage, see chapter 6
"Transport and storage".
In case of complaints, please contact Bosch Rexroth AG, see chapter 16.1 "List of
addresses".
Accessories such as valve subplates and valve mounting screws are not included in
the scope of delivery and must be ordered separately. See chapter 7.6 "Required
accessories".
5 Product information
For information on the performance and product description, please refer to
"Data sheet 24751-XE" of your valve.

Product information 17/52
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5.1 Product identification
5.1.1 Information on the name plate and the valve solenoid housing
The meaning of the information on the name plate applicable to the non-electrical
part of the valve can be seen from the numbered fields of the following table.
Fig. 1: Name plate for valves of size 10
Fig. 2: Name plate for valves of size 16, 25, 32
Table 5: Information on the name plate
No. Type of information Information or example
1 Manufacturer's logo Rexroth
2 Material no. of the valve e.g. MNR: R901034038
3 Type designation complete valve e.g. H-4WEH10H4X/
6BW230RNXEDZ2
4 Serial number of the valve e.g. SN: 0002111
5 Manufacturer's factory number e.g. 7081
6 Date of manufacture (year and week) e.g. FD: 03W01
7 Maximum operating pressure e.g. pmax 350 bar
8 Ambient temperature range –20°C ≤Ta ≤+60°C
9 Hydraulic symbol according to ISO 1219 Graphic

18/52 Product information
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No. Type of information Information or example
10 Designation of origin Made in Germany
11 Name and address of the manufacturer Bosch Rexroth AG D-97816
LOHR
12 Customer's or production order number e.g. 123456789012345678
13 Customer material number or additional information e.g. CNR: 1234567890
14 CE mark CE
15 Explosion protection mark Ex
16 Mark according to the explosion protection directive
2014/34/EU and mark for the type of protection of
the mechanical part according to EN 13463-5
II 2G c T4X
17 --- ---
18 --- ---
19 --- ---
95 Rexroth QR code QR code

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The meaning of the information on the name plate of the valve solenoid mounted on
the valve can be read in the correspondingly numbered fields of the following table.
Fig. 3: Solenoid name plate
Table 6: Information on the name plate
No. Type of information Information or example
1 Name/logo of the valve solenoid manufacturer Hydac electronic GmbH
2 Address of the valve solenoid manufacturer 66128 Saarbrücken,
Hauptstr. 27, Germany
3 Internal identification number e.g. EX-1516-001
4 Customer material number e.g. R1234567891
5 Nominal voltage e.g. 24 VDC
6 Rated current e.g. 0.708 A
7 Electrical characteristic values:
Duty cycle according to IEC 34-1 (VDE 0580) and frequency
e.g. S1(DB) 50 Hz.
8 Admissible ambient temperature range
e.g. –20°C ≤ Ta ≤ +55°C1)
9 Explosion protection mark Ex
10 Type examination certificate number KEMA 02ATEX2240 X
11 Mark for protection class according to explosion protection
directive2014/34/EU
II 2G
12 Mark for the type of protection according to EN 60079-7 or
EN60079-18
Ex eb mb IIC T4 Gb
13 CE mark and identification of notified body CE 0158
14 IEC Certificate of Conformity IECEx DEK 12.0068X
15 Mark for the type of protection according to EN 60079-7 or
EN60079-18
Ex eb mb IIC T4 Gb
16 Serial number of the valve solenoid and date of production e.g. X110125 / 302
17 Application note Line/cable ≥ 110°C
18 Rated current for external miniature fuse e.g. 800 mA
19 Rated voltage for external miniature fuse e.g. 250 V
20 Hydac data matrix code Data matrix code
1) Dependent on valve sizes and the configuration of the solenoid coils, higher ambient temperatures up to 70°C are
admissible. Also observe the "Special conditions for safe use" in "Data sheet 24751-XE".
1
2
34
56
7
8
10
9
11 12 13
14 15
18 19
17
16
13
13
20

20/52 Product information
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5.1.2 Explosion protection marking
According to EU directive 1999/92/EC, the user/machine end-user has to classify
potentially explosive atmospheres into zones. In the following table, the
corresponding zones for device groups and categories are shown.
The valve may only be used in the areas and zones which correspond to the device
group and category. During use, also observe the other information on explosion
protection in "Data sheet 24751-XE".
Table 7: Device groups and categories
Zones, device groups
andcategories
Device group
according to
2014/34/EU
Category
according to
2014/34/EU
Area of application, properties (excerpt from the directives)
Usable in zone
according to
1999/92/EC
I M1 Areas susceptible to firedamp (=device group I), i.e.: underground mines and their
pitheads. If there is an explosive atmosphere, the operation can continue.
Very high level of safety.
-
I M2 Areas susceptible to firedamp (=device group I), i.e.: underground mines and their
pitheads. If there is an explosive atmosphere, it must be possible to switch off
thedevice.
High level of safety.
-
II 1G Potentially explosive atmospheres in which explosive gasses, mists or vapors
(=device group II) occur permanently or for a long time or frequently.
Corresponds to zone 0 according to directive 1999/92/EC.
Very high level of safety.
0, 1, 2
II 2G Potentially explosive atmospheres in which explosive gasses, mists or vapors
(=device group II) occur sometimes.
Corresponds to zone 1 according to directive 1999/92/EC.
High level of safety.
1, 2
II 3G Potentially explosive atmospheres in which explosive gasses, mists or vapors
(=device group II) do not normally occur or only rarely or for a short time.
Corresponds to zone 2 according to directive 1999/92/EC.
Standard level of safety.
2
II 1D Potentially explosive atmospheres in which explosive dust/air mixtures (=device
group II) occur permanently or for a long time or frequently.
Corresponds to zone 20 according to directive 1999/92/EC.
Very high level of safety.
20, 21, 22
II 2D Potentially explosive atmospheres in which explosive dust/air mixtures (=device
group II) occur sometimes.
Corresponds to zone 21 according to directive 1999/92/EC.
High level of safety.
21, 22
II 3D Potentially explosive atmospheres in which an explosive atmosphere due to blown
up dust (=device group II) does not normally occur or only rarely or for a short time.
Corresponds to zone 22 according to directive 1999/92/EC.
Standard level of safety.
22