EN 50176:2009

Stationary electrostatic application equipment for ignitable liquid coating material - Safety requirements

1.1 This European Standard specifies the requirements for stationary electrostatic application equipment for ignitable liquid coating materials and for hard to ignite liquid coating materials to be used in explosive atmospheres generated by their own spray cloud. A distinction is made between spraying systems corresponding to EN 50050 and spraying systems designed for higher discharge energies and/or currents. This European Standard also specifies the design-related requirements for a safe operation of the stationary equipment including its electrical installation. 1.2 This European Standard considers four types of electrostatic spraying systems; see 5.1 for more details. 1.3 This European Standard deals with all hazards significant for the electrostatic spraying of coating materials, which could also contain small quantities of added metal particles, if the work is carried out under conditions recommended by the manufacturer. In particular, this includes ignition hazards resulting from the generated explosive atmosphere, and the protection of persons from electric shocks. 1.4 This stationary equipment is classified as equipment of group II, category 2G or category 3G for use in potentially explosive areas of zone 1 or 2, respectively. NOTE For other safety aspects like – zone classification of the areas in and around spray booths, see EN 12215:2004, 5.7.2.3; – zone classification of other areas with explosive atmosphere, see EN 60079-10-1; – selection, installation and application of other electrical and non electrical equipment in areas with explosion hazard, see EN 60079-14 and EN 12215:2004, 5.7.2.5; – health protection (for instance, noise), see also EN 12215:2004, 5.5 and EN 14462; – cleaning of spraying areas, see instruction manual of the spraying equipment; – fire prevention and protection (for instance fire hazards due to other sources) see also EN 12215:2004, 5.7.1. Design-related measures for reducing the generation of noise of the stationary equipment for electrostatic coating are given in EN ISO 11688 1. See also EN 14462.

Stationäre Ausrüstung zum elektrostatischen Beschichten mit entzündbaren flüssigen Beschichtungsstoffen - Sicherheitsanforderungen

Matériels stationnaires de projection électrostatique de produit liquide de revêtement inflammable - Exigences de sécurité

Vgrajena oprema za elektrostatični nanos vnetljivih tekočin za prevleke - Varnostne zahteve

Ta evropski standard opredeljuje zahteve za vgrajeno opremo za elektrostatični nanos vnetljivih tekočin za prevleke in za težko vnetljive tekočine za prevleke za uporabo v eksplozivnih atmosferah, ustvarjenih z njihovim lastnim oblakom razpršila. Razlikujemo med razpršilnimi sistemi, ki ustrezajo EN 50050 in razpršilnimi sistemi, oblikovanimi za višje pretočne energije in/ali tokove. Ta evropski standard prav tako opredeljuje oblikovne zahteve za varno delovanje vgrajene opreme, vključno z njeno električno napeljavo. 1.2 Ta evropski standard upošteva štiri tipe elektrostatičnih razpršilnih sistemov; za več podrobnosti glej točko 5.1. 1.3 Ta evropski standard obravnava vse nevarnosti, značilne za elektrostatično razprševanje prevlek, ki lahko vsebujejo tudi manjše količine dodanih kovinskih delcev, če je delo izvedeno pod pogoji po priporočilu proizvajalca. Zlasti to vključuje nevarnost vžiga, ki izhaja iz ustvarjene eksplozivne atmosfere, in varovanje oseb pred električnimi šoki. 1.4 Ta vgrajena oprema je razvrščena kot oprema skupine II, kategorije 2G ali kategorije 3G za uporabo na potencialno eksplozivnih območjih cone 1 oziroma 2.

General Information

• Status: Published
• Publication Date: 15-Oct-2009
• Withdrawal Date: 31-Aug-2012
• ICS: 87.100 - Paint coating equipment
• Technical Committee: CLC/TC 31 - Electrical apparatus for explosive atmospheres - General requirements
• Drafting Committee: CLC/SC 31-8 - Electrostatic painting and finishing equipment
• Parallel Committee: IEC/TC 31 - Electrical apparatus for potentially explosive atmospheres
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 16-Oct-2009
• Completion Date: 16-Oct-2009
• Directive: 2014/34/EU - Directive 2014/34/EU Of The European Parliament And Of The Council of 26 February 2014 on the harmonisation of the laws of the Member States relating to equipment and protective systems intended for use in potentially explosive atmospheres (recast)
• Directive: 94/9/EC - Directive 94/9/EC of the European Parliament and the Council of 23 March 1994 on the approximation of the laws of the Member States concerning equipment and protective systems intended for use in potentially explosive atmospheres
• Ref Project: SIST EN 50176:2010 - Stationary electrostatic application equipment for ignitable liquid coating material - Safety requirements

Relations

• Replaces: EN 50176:1996 - Automatic electrostatic spraying installations for flammable liquid spraying material
• Effective Date: 28-Jan-2023
• Revised: FprEN 50176 - Automatic electrostatic application systems for ignitable coating materials - Safety requirements
• Effective Date: 10-Mar-2020

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 50176:2010
01-januar-2010
1DGRPHãþD
SIST EN 50176:1998
9JUDMHQDRSUHPD]DHOHNWURVWDWLþQLQDQRVYQHWOMLYLKWHNRþLQ]DSUHYOHNH
9DUQRVWQH]DKWHYH

Stationary electrostatic application equipment for ignitable liquid coating material - Safety

requirements

Stationäre Ausrüstung zum elektrostatischen Beschichten mit entzündbaren flüssigen

Beschichtungsstoffen - Sicherheitsanforderungen

Matériel stationaire de projection électrostatique de produit à projeter liquide inflammable

- Exigences de sécurité
Ta slovenski standard je istoveten z: EN 50176:2009
ICS:
29.260.20 (OHNWULþQLDSDUDWL]D Electrical apparatus for
HNVSOR]LYQDR]UDþMD explosive atmospheres
87.100 Oprema za nanašanje Paint coating equipment
premazov
SIST EN 50176:2010 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST EN 50176:2010
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SIST EN 50176:2010
EUROPEAN STANDARD
EN 50176
NORME EUROPÉENNE
October 2009
EUROPÄISCHE NORM
ICS 87.100 Supersedes EN 50176:1996
English version
Stationary electrostatic application equipment
for ignitable liquid coating material -
Safety requirements
Matériels stationnaires de projection Stationäre Ausrüstung
électrostatique de produit liquide zum elektrostatischen Beschichten
de revêtement inflammable - mit entzündbaren flüssigen
Exigences de sécurité Beschichtungsstoffen -
Sicherheitsanforderungen

This European Standard was approved by CENELEC on 2009-09-01. CENELEC members are bound to

comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European

Standard the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on

application to the Central Secretariat or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other

language made by translation under the responsibility of a CENELEC member into its own language and

notified to the Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Cyprus, the

Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,

Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia,

Slovenia, Spain, Sweden, Switzerland and the United Kingdom.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
Central Secretariat: Avenue Marnix 17, B - 1000 Brussels

© 2009 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.

Ref. No. EN 50176:2009 E
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SIST EN 50176:2010
EN 50176:2009 – 2 –
Foreword

This European Standard was prepared by SC 31-8, Electrostatic painting and finishing equipment, of

Technical Committee CENELEC TC 31, Electrical apparatus for potentially explosive atmospheres.

The text of the draft was submitted to the formal vote and was approved by CENELEC as EN 50176 on

2009-09-01.
This European Standard supersedes EN 50176:1996.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2010-09-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2012-09-01

This European Standard has been prepared under a mandate given to CENELEC by the European

Commission and the European Free Trade Association and covers essential requirements of

EC Directive 94/9/EC. See Annex ZZ.

CENELEC/TC 31 as the responsible committee has concluded that this new edition of EN 50176 does

not contain substantial changes regarding the ESRs.

The State of the Art is included in Annex ZY “Significant changes between this European Standard and

EN 50176:1996”.
___________
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SIST EN 50176:2010
– 3 – EN 50176:2009
Contents

0 Introduction ........................................................................................................................................4

0.1 Process ...................................................................................................................................4

0.2 Explosion hazards ...................................................................................................................4

0.3 Electric hazards .......................................................................................................................4

1 Scope ................................................................................................................................................5

2 Normative references ........................................................................................................................5

3 Definitions ..........................................................................................................................................6

4 General requirements ........................................................................................................................9

5 Requirements for the equipment .....................................................................................................10

5.1 Electrostatic spraying systems ..............................................................................................10

5.2 Requirements for spraying systems of category 3G .............................................................11

5.3 Special requirements for spraying systems of category 2G ..................................................12

5.4 Spraying area ........................................................................................................................13

5.5 High voltage supply ...............................................................................................................13

5.6 Electric requirements ............................................................................................................14

5.7 Grounding measures .............................................................................................................14

5.8 Supply for coating material ....................................................................................................14

6 Testing .............................................................................................................................................15

6.1 Tests of the high voltage cables ............................................................................................15

6.2 Test of the insulating spraying material supply hose.............................................................15

6.3 Tests of the stationary equipment .........................................................................................15

6.4 Specific test requirements for spraying systems of type B-L, type C-L or type D-L

category 2G ...........................................................................................................................17

7 Information for use ..........................................................................................................................18

7.1 General..................................................................................................................................18

7.2 Instruction manual .................................................................................................................18

7.3 Marking .................................................................................................................................19

7.4 Warning sign .........................................................................................................................21

Annex A (informative) Ignitability of water-based paints .........................................................................22

Bibliography ............................................................................................................................................24

Annex ZY (informative) Significant changes between this European Standard and

EN 50176:1996 ................................................................................................25

Annex ZZ (informative) Coverage of Essential Requirements of EC Directives ...................................26

Figure

Figure 1 – Test assembly according to 6.4.2 ..........................................................................................17

Tables

Table 1 – Electrostatic spraying systems for ignitable and hard to ignite liquid coating materials –

Fields of application .................................................................................................................10

Table 2 – Requirements for electrostatic spraying systems of category 3G for ignitable and hard

to ignite liquid coating materials ..............................................................................................11

Table 3 – Survey of tests ........................................................................................................................15

Table 4 – Test intervals ..........................................................................................................................19

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SIST EN 50176:2010
EN 50176:2009 – 4 –
0 Introduction
0.1 Process

During the electrostatic coating process the liquid coating material is transported to an electrostatic

spraying device where it is converted to droplets by mechanical forces and by the influence of an

electric field. During this atomising process the droplets are charged by high voltage of some 10 kV

and a spray cloud is generated. The charged droplets are attracted by and applied to the earthed

workpiece.

Droplets, which are not applied to the workpiece (overspray) are removed by a suction device or by

other means.

After the coating process the coated workpieces are introduced into a dryer where the solvent is

evaporated and a dry film of coating material is generated.
0.2 Explosion hazards
An explosion could occur, if

– the concentration of sprayed liquid ignitable coating materials in air is within the explosion limits,

– an ignition source of appropriate energy for this explosive atmosphere is present.

Ignition sources could be, for instance, a hot surface, an open flame, an electric arc or a spark.

An explosion could be prevented, if one – or better both – conditions are avoided. Because it is very

difficult to exclude the possibility of ignitable discharges completely, the main focus should be the

prevention of ignitable concentrations of explosive atmosphere.

0.2.1 Mixtures of ignitable coating materials and air could only explode within a given range of

concentration, but not, if the concentration is above or below this range.

NOTE If an explosive mixture of coating materials and air is trapped in a closed room, an explosion could lead to a fatal

increase of pressure.

0.2.2 Particular attention should be paid to the prevention of electrostatic charges on different

surfaces, which are in the vicinity of the spray cloud. This could apply to workpieces during the coating

process or the reciprocating devices and the mounting parts of the spraying system etc.

0.3 Electric hazards

0.3.1 Electric shock (by direct or indirect contact) could be generated, for instance, by contact with

– live parts, which are not insulated for operational reasons,

– conductive parts, which are not under dangerous voltage during normal operation, but in case of

failure,

– insulated live parts whose insulation is insufficient or has been damaged due to mechanical

influences.
0.3.2 Inadequate grounding could occur, for instance, due to
– faulty connections to the protective grounding system,
– a too high resistance to ground.

0.3.3 Hazards could occur, for instance, if hazardous malfunctions (e.g. shortcut of electronic

safety circuits, of access guards to dangerous areas or of warning devices) occur due to interferences

of the high voltage equipment and the components of control and safety systems.

0.3.4 Hazardous electrostatic discharges could be generated, for instance, by non-earthed

conductive components or by large insulating surfaces, especially if they are backed with conductive

material.
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SIST EN 50176:2010
– 5 – EN 50176:2009
1 Scope

1.1 This European Standard specifies the requirements for stationary electrostatic application

equipment for ignitable liquid coating materials and for hard to ignite liquid coating materials to be used

in explosive atmospheres generated by their own spray cloud. A distinction is made between spraying

systems corresponding to EN 50050 and spraying systems designed for higher discharge energies

and/or currents.

This European Standard also specifies the design-related requirements for a safe operation of the

stationary equipment including its electrical installation.

1.2 This European Standard considers four types of electrostatic spraying systems; see 5.1 for

more details.

1.3 This European Standard deals with all hazards significant for the electrostatic spraying of

coating materials, which could also contain small quantities of added metal particles, if the work is

carried out under conditions recommended by the manufacturer. In particular, this includes ignition

hazards resulting from the generated explosive atmosphere, and the protection of persons from

electric shocks.

1.4 This stationary equipment is classified as equipment of group II, category 2G or category 3G

for use in potentially explosive areas of zone 1 or 2, respectively.
NOTE For other safety aspects like

– zone classification of the areas in and around spray booths, see EN 12215:2004, 5.7.2.3;

– zone classification of other areas with explosive atmosphere, see EN 60079-10-1;

– selection, installation and application of other electrical and non electrical equipment in areas with explosion hazard, see

EN 60079-14 and EN 12215:2004, 5.7.2.5;

– health protection (for instance, noise), see also EN 12215:2004, 5.5 and EN 14462;

– cleaning of spraying areas, see instruction manual of the spraying equipment;

– fire prevention and protection (for instance fire hazards due to other sources) see also EN 12215:2004, 5.7.1.

Design-related measures for reducing the generation of noise of the stationary equipment for electrostatic coating are given in

EN ISO 11688-1. See also EN 14462.
2 Normative references

The following referenced documents are indispensable for the application of this document. For dated

references, only the edition cited applies. For undated references, the latest edition of the referenced

document (including any amendments) applies.
EN 1081, Resilient floor coverings – Determination of the electrical resistance

EN 1127-1, Explosive atmospheres – Explosion prevention and protection – Part 1: Basic concepts

and methodology

EN 1149-5, Protective clothing – Electrostatic properties – Part 5: Material performance and design

requirements

EN 12215:2004, Coating plants – Spray booths for application of organic liquid coating materials –

Safety requirements

EN 13463-1, Non-electrical equipment for use in potentially explosive atmospheres - Part 1: Basic

method and requirements
EN 13478, Safety of machinery – Fire prevention and protection
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SIST EN 50176:2010
EN 50176:2009 – 6 –

EN 50050, Electrical apparatus for potentially explosive atmospheres – Electrostatic hand-held

spraying equipment

EN 60079-0, Electrical apparatus for explosive gas atmospheres – Part 0: General requirements

(IEC 60079-0)

EN 60204-1, Safety of machinery – Electrical equipment of machines – Part 1: General requirements

(IEC 60204-1)

EN 60529:1991, Degrees of protection provided by enclosures (IP code) (IEC 60529:1989)

EN 61340-4-1, Electrostatics – Part 4-1: Standard test methods for specific applications – Electrical

resistance of floor coverings and installed floors (IEC 61340-4-1)

EN 62061, Safety of machinery – Functional safety of safety-related electrical, electronic and

programmable electronic control systems (IEC 62061)

EN ISO 12100-1, Safety of machinery – Basic concepts, general principles for design –

Part 1: Basic terminology, methodology (ISO 12100-1)

EN ISO 12100-2, Safety of machinery – Basic concepts, general principles for design –

Part 2: Technical principles (ISO 12100-2)

EN ISO 13849-1, Safety of machinery – Safety-related parts of control systems – General principles for

design (ISO 13849-1)

EN ISO 20344, Personal protective equipment – Test method for footwear (ISO 20344)

3 Definitions
For the purposes of this document, the following terms and definitions apply.
3.1

stationary electrostatic application equipment for ignitable liquid coating material

equipment in which the electrostatic spraying equipment is either fixed stationary (e.g. on supports)

and is operated automatically or is guided by reciprocators (e.g. robots).
In general, the equipment comprises the following:
– spray booth;
– spraying area;
– spraying system;
– fixtures for workpieces;
– conveyors;
– grounding system;
– forced ventilation;
– fire prevention and protection equipment
3.2
spraying system

devices for application of liquid coating material by means of electrostatic charge.

In general, the spraying system consists of the following compounds:
– device for the supply of coating material;
– high voltage electrode;
– high voltage supply system;
– spraying device
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SIST EN 50176:2010
– 7 – EN 50176:2009
3.3
high voltage supply system
system consisting in general of the following components:

─ low voltage section with devices for switching on and off the unit and for adjustment, control,

regulation, limitation and monitoring of current and voltage, as well as the required connecting

cables;
─ high voltage generator;
─ high voltage switching device;
─ high voltage cable;
─ high voltage plug-and-socket connector
3.4
spraying area

area, closed or not, in which the coating material is applied to the workpiece by the electrostatic

spraying system
3.5
dangerous discharge

discharge which generates the hazard of ignition of explosive mixtures or of electric shock

3.6
workpiece
article to which the coating material is applied
3.7
ignitable liquid coating materials

sprayed materials, especially varnishes, which could be ignited by an effective ignition source and

which continue to burn after the ignition source has been removed or may react in the form of an

explosion

NOTE A formula for the estimation of ignitability on the basis of the composition of the coating material is given in Annex B.

3.8
hard to ignite liquid coating materials

sprayed materials, especially varnishes, which could be ignited by an effective ignition source with an

energy of 2 J or above and which continue to burn after the ignition source has been removed, or may

react in the form of an explosion

NOTE A formula for the estimation of ignitability on the basis of the composition of the coating material is given in Annex B.

3.9
explosive atmosphere

mixture of air, under atmospheric conditions, and ignitable substances in the form of gas, vapour, mist,

powder or flock, in such proportions that it can be ignited by effective ignition sources, such as

excessive temperature, arcs or sparks [see EN 1127-1]
3.10
lower explosion limit (LEL)

concentration of ignitable gas, vapour, mist, powder or flock in air below which an explosive

atmosphere will not be formed
3.11
average concentration of ignitable coating materials in air

mass of the ignitable coating material applied in the spraying area divided by the volume of air

exchanged during the same period of time in the spraying area
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SIST EN 50176:2010
EN 50176:2009 – 8 –
3.12
discharge energy

energy discharged from a conductive part of the installation in form of a spark which could cause both

electric shock to a person and an ignition of an explosive atmosphere
3.13
antistatic footwear

footwear that has a resistance to earth via its sole, which is low enough to prevent the build-up of

electrostatic charges capable to produce an incendive discharge [see EN ISO 20344]

NOTE A necessary electric insulating resistance to prevent electric shocks is not contradictory to this definition.

3.14
antistatic clothes

clothes that have a resistance to earth, which is low enough to prevent the build-up of electrostatic

charges capable to produce an incendive discharge [see EN 1149-5]

NOTE A necessary electric insulating resistance to prevent electric shocks is not contradictory to this definition.

3.15
antistatic floor

floor that has a resistance to earth, which is low enough to prevent the build-up of electrostatic charges

capable to produce an incendive discharge
3.16
minimum air volume flow

air volume flow of the forced ventilation which shall be ensured in case of worst operational conditions

as described in 5.4.1 and 5.4.4
3.17
accessories

accessories are all devices, components and other equipment, except for 3.2 of this standard

3.18
constant-voltage operation

closed control circuit system with direct feedback of the actual value of the output high voltage. During

the constant-voltage operation the adjusted output high voltage is maintained constant up to the

capacitance of the high voltage part via a control device, independent of the variable operational

current
NOTE In general the symbol for this type of operation is U .
3.19
voltage-controlled operation

open control circuit system without feedback of the output high voltage. During the voltage-controlled

operation the output high voltage is adjusted generally at a defined operational current. The output high

voltage, however, is not maintained constant by a control device, it varies depending on the operational

current and the on-load behaviour of the high voltage device
NOTE In general the symbol for this type of operation is U .
3.20
constant current operation

closed control circuit system with direct feedback of the actual value of the high voltage current to a

control device. In doing so, the operational current is maintained constant, and the output high voltage

varies load-dependently between a minimum and a maximum value defined by the process

NOTE In general the symbol for this type of operation is I .
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SIST EN 50176:2010
– 9 – EN 50176:2009
3.21
operational current

current which flows within the high voltage circuit during failure-free operation

NOTE In general the symbol for the operational current is I .
3.22
overcurrent

current occurring during a malfunction, exceeding the operational current of the high voltage circuit and

giving rise to expect that in voltage-controlled and constant voltage operation hazardous discharges or

arcs between high voltage parts and earthed parts of the plant could occur in case the safety distance

drops below the permissible limit
NOTE In general the symbol for overcurrent in the high voltage circuit is I .
3.23
minimum voltage

voltage of the high voltage circuit giving rise to expect that in constant current operation hazardous

discharges or arcs could occur between high voltage parts and earthed parts of the plant, in case the

safety distance drops below the permissible limit

NOTE In general the symbol for minimum voltage in the high voltage circuit is U .

min
3.24
disconnection threshold

limit value for current I or voltage U . In case of any deviation of the actual value from the threshold

ü min
value, disconnection of the high voltage supply is activated
3.25
locally acting fire extinguishing system

device which protects the highly hazardous area between spraying system and workpiece and is

actuated immediately in case of fire. It shall meet the special requirements of electrostatic coating

3.26
skilled person

person who, due to technical training, experience and recent occupational activities, has sufficient

knowledge in the field of electrostatic coating with stationary equipment, is familiar with the relevant

and generally accepted technical rules, and thus is able to check and evaluate the occupationally safe

state of coating plants
3.27
repeated inspection

inspection of the entire electrical equipment, systems and plants to be carried out at regular intervals

4 General requirements

4.1 All equipment and components shall be designed and constructed according to good

engineering practice and comply with the required categories for group II devices to ensure avoidance

of any ignition source.

4.2 All accessories shall be, if possible, outside the areas with explosion hazards.

4.3 All accessories used in areas with explosion hazards shall comply with the requirements of

EN 60079-0 and/or EN 13463-1.

4.4 An appropriate grounding of the different surfaces shall be provided. Special care shall be

taken that sufficient grounding is maintained by the hangers. These hangers shall be designed in such

a way that deposits of coating materials are minimized.
---------------------- Page: 11 ----------------------
SIST EN 50176:2010
EN 50176:2009 – 10 –

4.5 Stationary equipment shall be designed and constructed to satisfy the intended function as

given by the limitations of the manufacturer safely even in case of varying environmental conditions,

influence of external voltages, exposure to humidity, vibrations, contaminations as well as other

environmental influences. Stationary equipment shall be suitable for the intended mechanical and

thermal demands and shall withstand the effects of present or predictable aggressive materials.

4.6 Spraying systems of category 2G, with exception of the spraying device, shall have at last IP-

protection IP64 according to EN 60529 and spraying systems of category 3G, with exception of the

spraying device, shall have at last IP-protection IP54 according to EN 60529.

4.7 Safety devices shall function independently of the measuring, control and regulation devices

required for operation. The failure of a safety device shall be detected, if possible, by appropriate

technical measures in an adequate period so that hazardous conditions are not likely to occur.

Fundamentally the fail-safe principle shall be applied.

In case of a failure of safety devices the stationary equipment shall be led to a safe condition as far as

possible.

4.8 If the safety functions of the safety devices of the stationary equipment according to Clause 5

and Table 2 depend on software, particular attention shall be paid to the risks due to program errors.

This requirement is satisfied by observance of the requirements for the safety integrity level 2

according to EN 62061.
5 Requirements for the equipment
5.1 Electrostatic spraying systems

Depending on the maximal discharge energy that can occur, electrostatic spraying systems are

categorised in four types according to Table 1.
Table 1 – Electrostatic spraying systems for ignitable and hard to ignite
liquid coating materials – Fields of application
Types Discharge energy Hazard by Hazard
(“L” for liquid
ignitable discharge by
coating during processing electric shock
materials)
Ignitable coating Hard to ignite
material coating material
(see 3.7) (see 3.8)
Type A-L < 0,24 mJ No No No
Type B-L < 350 mJ Yes No No
Type C-L < 2 J Yes No Yes
Type D-L > 2 J Yes Yes Yes

NOTE 1 The discharge energy W can be calculated by the following formula: W = ½ C · U². If resistors, semi-conductors or

liquid conductors are present, the calculation of W results in too high values. Alternatively, the discharge energy can be

determined by measurement.

NOTE 2 Hazards listed in the table are adequately prevented by observing this standard.

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SIST EN 50176:2010
– 11 – EN 50176:2009
5.2 Requirements for spraying systems of category 3G
The requirements related to the different types are listed in Table 2.

Table 2 – Requirements for electrostatic spraying systems of category 3G for ignitable

and hard to ignite liquid coating materials
Subclause Requirements Type A-L Type B-L Type C-L Type D-L
a a
5.2.1 Distance workpiece-spraying system No Yes Yes Yes
5.2.2 Disconnection of high voltage No Yes Yes Yes
5.5.2 Protection against contact No No Yes Yes
5.2.3 Personal protection No No Yes Yes
5.2.4 Ignition protection/cleaning agent Yes Yes Yes Yes
a a
5.2.5 Locally acting fire extinguishing No Yes Yes Yes
equipment

Not required if only hard to ignite liquid coating materials are processed (see 3.8).

Satisfied by construction.

A locally acting fire extinguishing equipment is not required when using category 2G equipment of types B-L, C-L and D-L

only in areas with explosion hazards of zone 2.
5.2.1 Distance workpiece – spraying system

The distance between the workpieces and the parts of the spraying system under high voltage shall be

so great that an electrical discharge is prevented du
...

SLOVENSKI STANDARD
oSIST prEN 50176:2007
01-november-2007
,QãWDODFLMH]DDYWRPDWVNRRSUHPR]DHOHNWURVWDWLþQREUL]JDQMH]YQHWOMLYLPL
WHNRþLQDPL]DEDUYDQMH

Stationary electrostatic application equipment for ignitable liquid coating material - Safety

requirements

Stationäre Ausrüstung zum elektrostatischen Beschichten mit entzündbaren flüssigen

Beschichtungsstoffen - Sicherheitsanforderungen

Matériel stationaire de projection électrostatique de produit a projeter liquide inflammable

- Exigences de sécurité
Ta slovenski standard je istoveten z: prEN 50176:2007
ICS:
87.100 Oprema za nanašanje Paint coating equipment
premazov
oSIST prEN 50176:2007 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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DRAFT
EUROPEAN STANDARD
prEN 50176
NORME EUROPÉENNE
September 2007
EUROPÄISCHE NORM
ICS 87.100 Will supersede EN 50176:1996
English version
Stationary electrostatic application equipment
for ignitable liquid coating material -
Safety requirements
Matériel stationaire de projection Stationäre Ausrüstung zum
électrostatique de produit à projeter elektrostatischen Beschichten mit
liquide inflammable - entzündbaren flüssigen
Exigences de sécurité Beschichtungsstoffen -
Sicherheitsanforderungen

This draft European Standard is submitted to CENELEC members for CENELEC enquiry.

Deadline for CENELEC: 2007-11-09.
It has been drawn up by CLC/SC 31-8.

If this draft becomes a European Standard, CENELEC members are bound to comply with the CEN/CENELEC

Internal Regulations which stipulate the conditions for giving this European Standard the status of a national

standard without any alteration.

This draft European Standard was established by CENELEC in three official versions (English, French, German).

A version in any other language made by translation under the responsibility of a CENELEC member into its own

language and notified to the Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Cyprus, the

Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,

Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,

Sweden, Switzerland and the United Kingdom.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to

change without notice and shall not be referred to as a European Standard.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
Central Secretariat: rue de Stassart 35, B - 1050 Brussels

© 2007 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.

Project: 16944 Ref. No. prEN 50176:2007 E
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prEN 50176:2007 – 2 –
Foreword

This draft European Standard was prepared by SC 31-8, Electrostatic painting and finishing

equipment, of Technical Committee CENELEC TC 31, Electrical apparatus for explosive atmospheres.

It is submitted to the CENELEC enquiry.
This European Standard will supersede EN 50176:1996.

This draft European Standard has been prepared under a mandate given to CENELEC by the

European Commission and the European Free Trade Association and covers essential requirements

of EC Directive 94/9/EC. See Annex ZZ.
_____________________
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Contents

0 Introduction........................................................................................................................................4

0.1 Process ...................................................................................................................................4

0.2 Explosion hazard.....................................................................................................................4

0.3 Electric hazards.......................................................................................................................4

1 Scope ................................................................................................................................................5

2 Normative references ........................................................................................................................5

3 Definitions..........................................................................................................................................6

4 General requirements........................................................................................................................9

5 Requirements for the equipment.....................................................................................................10

5.1 Electrostatic spraying systems..............................................................................................10

5.2 Requirements for spraying systems of category 3................................................................10

5.3 Special requirements for spraying systems of category 2G..................................................12

5.4 Spraying area ........................................................................................................................13

5.5 High voltage supply...............................................................................................................13

5.6 Electric requirements ............................................................................................................14

5.7 Grounding measures.............................................................................................................14

6 Testing.............................................................................................................................................14

6.1 Tests of the high voltage cables............................................................................................14

6.2 Tests of the stationary equipment.........................................................................................14

6.3 Specific test requirements for spraying systems of type B-L, type C-L or type D-L

category 2G...........................................................................................................................16

7 Information for use ..........................................................................................................................17

7.1 General..................................................................................................................................17

7.2 Instruction handbook.............................................................................................................17

7.3 Marking .................................................................................................................................18

7.4 Warning sign .........................................................................................................................20

Annex ZZ (informative) Coverage of Essential Requirements of EC Directives ...................................21

Bibliography ............................................................................................................................................22

Figure

Figure 1 – Test assembly according to 6.3.2..........................................................................................16

Tables

Table 1 – Electrostatic spraying systems for ignitable and hard to ignite liquid coating materials –

Fields of application.........................................................................................................................10

Table 2 – Requirements for electrostatic spraying systems of category 3 for ignitable and hard to

ignite liquid coating materials ..........................................................................................................11

Table 3 – Survey of tests........................................................................................................................15

Table 4 – Test intervals ..........................................................................................................................18

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prEN 50176:2007 – 4 –
0 Introduction
0.1 Process

During the electrostatic coating process the liquid coating material is transported to an electrostatic

spraying device where it is converted to droplets by mechanical forces and by the influence of an

electric field. During this atomising process the droplets are charged by high voltage of some 10 kV

and a spray cloud is generated. The charged droplets are attracted by and applied to the earthed

workpiece.

Droplets, which are not applied to the workpiece (overspray) are removed by a suction device or by

other means.

After the coating process the coated workpieces are introduced into a dryer where the solvent is

evaporated and a dry film of coating material is generated.
0.2 Explosion hazard
An explosion could occur, if

– the concentration of sprayed liquid ignitable coating materials in air is within the explosion limits,

– an ignition source of appropriate energy for this explosive atmosphere is present.

Ignition sources could be, for instance, a hot surface, an open flame, an electric arc or a spark.

An explosion could be prevented, if one – or better both – conditions are avoided. Because it is very

difficult to exclude the possibility of discharges completely, the main focus should be the prevention of

ignitable concentrations.

0.2.1 Mixtures of ignitable coating materials and air could only explode within a given range of

concentration, but not, if the concentration is above or below this range.

NOTE If an explosive cloud of coating materials is trapped in a closed room, an explosion could lead to a fatal increase of

pressure.

0.2.2 Particular attention should be paid to the prevention of electrostatic charges on different

surfaces, which are in the vicinity of the spray cloud. This could apply to workpieces during the coating

process or the reciprocating devices and the mounting parts of the spraying system etc.

0.3 Electric hazards

0.3.1 Electric shock (by direct or indirect contact) could be generated, for instance, by contact with

– live parts, which are not insulated for operational reasons,

– conductive parts, which are not under dangerous voltage during normal operation, but in case of

failure,

– insulated live parts whose insulation is insufficient or has been damaged due to mechanical

influences.
0.3.2 Inadequate grounding could result, for instance, from
– faulty connections to the protective grounding system,
– a too high resistance to ground.

0.3.3 Hazards could occur, for instance, if hazardous malfunctions (e.g. shortcut of electronic

safety circuits, of access guards to dangerous areas or of warning devices) occur due to interferences

of the high voltage equipment and the components of control and safety systems.

0.3.4 Hazardous electrostatic discharges could be generated, for instance, by non-earthed

conductive components or by large insulating surfaces, especially if they are backed with conductive

material.
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1 Scope

1.1 This European Standard specifies the requirements for stationary electrostatic equipment for

ignitable liquid coating materials and for hard to ignite liquid coating materials to be used in explosive

atmospheres generated by their own spray cloud. A distinction is made between spraying systems

corresponding to EN 50050:2001 and spraying systems designed for higher discharge energies and/or

currents.

This European Standard also specifies the design-related requirements for a safe operation of the

stationary equipment including its electrical installation.

1.2 This European Standard considers four types of electrostatic spraying systems; see 5.1 for

more details.

1.3 This European Standard deals with all hazards significant for the electrostatic spraying of

coating materials, which could also contain small quantities of added metal particles, if the work is

carried out under conditions recommended by the manufacturer. In particular, this includes ignition

hazards resulting from the generated explosive atmosphere, and the protection of persons from

electric shocks.

1.4 This stationary equipment is classified as equipment of group II, category 2G or category 3G

for use in potentially explosive areas of zone 1 or 2, respectively.
NOTE For other safety aspects like

– zone classification of the areas in and around spray booths, see EN 12215:2004, 5.7.2.3;

– zone classification of other areas with explosive atmosphere, see EN 60079-10-1;

– selection, installation and application of other electrical and non electrical equipment in areas with explosion hazard, see

EN 60079-14 and EN 12215:2004, 5.7.2.5;

– health protection (for instance, noise), see also EN 12215:2004, 5.5 and EN 14462;

– cleaning of spraying areas, see instruction manual of the spraying equipment;

– fire prevention and protection (for instance fire hazards due to other sources) see also EN 12215:2004, 5.7.1.

Design-related measures for reducing the generation of noise of the stationary equipment for electrostatic coating are given in

EN ISO 11688-1. See also EN 14462.
2 Normative references

The following referenced documents are indispensable for the application of this document. For dated

references, only the edition cited applies. For undated references, the latest edition of the referenced

document (including any amendments) applies.
EN 1081, Resilient floor coverings – Determination of the electrical resistance

EN 1127-1, Explosive atmospheres – Explosion prevention and protection – Part 1: Basic concepts

and methodology

EN 1149-5 , Protective clothing – Electrostatic properties – Part 5: Performance requirements

EN ISO 12100-1, Safety of machinery – Basic concepts, general principles for design –

Part 1: Basic terminology, methodology (ISO 12100-1)

EN ISO 12100-2, Safety of machinery – Basic concepts, general principles for design –

Part 2: Technical principles (ISO 12100-2)
At draft stage.
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EN 12215:2004, Coating plants – Spray booths for application of organic liquid coating materials –

Safety requirements

EN 13463-1, Non-electrical equipment for potentially explosive atmospheres – Part 1: Basic method

and requirements
EN 13478:2001, Safety of machinery – Fire prevention and protection

EN ISO 20344, Personal protective equipment – Test method for footwear (ISO 20344)

EN 50050:2001, Electrical apparatus for potentially explosive atmospheres – Electrostatic hand-held

spraying equipment

EN 60079-0, Electrical apparatus for explosive gas atmospheres – Part 0: General requirements

(IEC 60079-0)

EN 60204-1, Safety of machinery – Electrical equipment of machines – Part 1: General requirements

(IEC 60204-1)
EN 60529, Degrees of protection provided by enclosures (IP code) (IEC 60529)

EN 61340-4-1, Electrostatics – Part 4-1: Standard test methods for specific applications – Electrical

resistance of floor coverings and installed floors (IEC 61340-4-1)

EN 62061, Safety of machinery – Functional safety of safety-related electrical, electronic and

programmable electronic control systems (IEC 62061)
3 Definitions
For the purposes of this document, the following terms and definitions apply.
3.1

stationary electrostatic application equipment for ignitable liquid coating material

equipment in which the electrostatic spraying equipment is either fixed stationary (e.g. on supports)

and is operated automatically or is guided by reciprocators (e.g. robots).
In general, the equipment comprises the following:
– spray booth,
– spraying area,
– spraying device,
– fixtures for workpieces,
– conveyors,
– grounding system,
– forced ventilation,
– fire prevention and protection equipment
3.2
spraying system

devices for application of liquid coating material by means of electrostatic charge.

In general, the spraying system consists of the following compounds:
– device for the supply of coating material,
– high voltage electrode,
– high voltage supply system,
– spraying device
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3.3
high voltage supply system
system consisting in general of the following compounds:

─ low voltage section with devices for switching on and off the unit and for adjustment, control,

regulation, limitation and monitoring of current and voltage, as well as the required connecting

cables,
─ high voltage generator,
─ high voltage switching device,
─ high voltage cable,
─ high voltage plug-and-socket connector
3.4
spraying area

area, closed or not, in which the coating material is applied to the workpiece by the electrostatic

spraying system
3.5
dangerous discharge

discharge which generates the hazard of ignition of explosive mixtures or of electric shock

3.6
workpiece
article to which the coating material is applied
3.7
ignitable liquid coating materials

sprayed materials, especially varnishes, which could be ignited by an effective ignition source and

which continue to burn after the ignition source has been removed or may react in the form of an

explosion
3.8
hard to ignite liquid coating materials

sprayed materials, especially varnishes, which could be ignited by an effective ignition source with an

energy of 2 J or above and which continue to burn after the ignition source has been removed, or may

react in the form of an explosion

NOTE A formula for the estimation of ignitability on the basis of the composition of the coating material is given in Annex A.

3.9
explosive atmosphere

mixture of air, under atmospheric conditions, and ignitable substances in the form of gas, vapour, mist,

powder or flock, in such proportions that it can be ignited by effective ignition sources, such as

excessive temperature, arcs or sparks (see EN 1127-1)
3.10
lower explosion limit (LEL)

concentration of ignitable gas, vapour, mist, powder or flock in air below which an explosive

atmosphere will not be formed
3.11
average concentration of ignitable coating materials in air

mass of the ignitable coating material applied to the spraying area divided by the volume of air

exchanged during the same period of time
3.12
discharge energy

energy discharged from a conductive part of the installation in form of a spark which could cause both

electric shock to a person and an ignition of an explosive atmosphere
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3.13
antistatic footwear

footwear that has a resistance to earth via its sole, which is low enough to prevent the build-up of

electrostatic charges capable to produce an incendive discharge (see EN ISO 20344)

NOTE A necessary electric insulating resistance to prevent electric shocks is not contradictory to this definition.

3.14
antistatic clothes

clothes that have a resistance to earth, which is low enough to prevent the build-up of electrostatic

charges capable to produce an incendive discharge (see EN 1149-5)

NOTE A necessary electric insulating resistance to prevent electric shocks is not contradictory to this definition.

3.15
antistatic floor

floor that has a resistance to earth, which is low enough to prevent the build-up of electrostatic charges

capable to produce an incendive discharge
3.16
minimum air volume flow

air volume flow of the forced ventilation which shall be ensured in case of worst operational conditions

as described in 5.4.1
3.17
accessories

accessories are all devices, components and other equipment, except for 3.2 of this standard

3.18
constant-voltage operation

closed control circuit system with direct feedback of the actual value of the output high voltage. During

the constant-voltage operation the adjusted output high voltage is maintained constant up to the

capacity of the high voltage part via a control device, independent of the variable operational current

NOTE In general the symbol for this type of operation is U .
3.19
voltage-controlled operation

open control circuit system without feedback of the output high voltage. During the voltage-controlled

operation the output high voltage is adjusted generally at a defined operational current. The output high

voltage, however, is not maintained constant by a control device, it varies depending on the operational

current and the on-load behaviour of the high voltage device
NOTE In general the symbol for this type of operation is U .
3.20
constant current operation

closed control circuit system with direct feedback of the actual value of the high voltage current to a

control device. In doing so, the operational current is maintained constant, and the output high voltage

varies load-dependently between a minimum and a maximum value defined by the process

NOTE In general the symbol for this type of operation is I .
3.21
operational current

current which flows within the high voltage circuit during failure-free operation

NOTE In general the symbol for the operational current is I .
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3.22
overcurrent

current occurring during a malfunction, exceeding the operational current of the high voltage circuit and

giving rise to expect that in voltage-controlled and constant voltage operation hazardous discharges or

arcs between high voltage parts and earthed parts of the plant could occur in case the safety distance

drops below the permissible limit
NOTE In general the symbol for overcurrent in the high voltage circuit is I .
3.23
minimum voltage

voltage of the high voltage circuit giving rise to expect that in constant current operation hazardous

discharges or arcs could occur between high voltage parts and earthed parts of the plant, in case the

safety distance drops below the permissible limit

NOTE In general the symbol for minimum voltage in the high voltage circuit is U .

min
3.24
disconnection threshold

limit value for current I or voltage U . In case of any deviation of the actual value from the threshold

ü min
value, disconnection of the high voltage supply is activated
3.25
locally acting fire extinguishing system

device which protects the highly hazardous area between spraying system and workpiece and is

actuated immediately in case of fire. It shall meet the special requirements of electrostatic coating

3.26
skilled person

person who, due to technical training, experience and recent occupational activities, has sufficient

knowledge in the field of electrostatic coating with stationary equipment, is familiar with the relevant

and generally accepted technical rules, and thus is able to check and evaluate the occupationally safe

state of coating plants
3.27
repeated inspection

inspection of the entire electrical equipment, systems and plants to be carried out at regular intervals

4 General requirements

4.1 All equipment and components shall be designed and constructed according to good

engineering practice and comply with the required categories for group II devices to ensure avoidance

of any ignition source.

4.2 All accessories shall be, if possible, outside the areas with explosion hazards.

4.3 All accessories used in areas with explosion hazards shall comply with the requirements of

EN 60079-0 and/or EN 13463-1.

4.4 An appropriate grounding of the different surfaces shall be provided. Special care shall be

taken that sufficient grounding is maintained by the hangers. These hangers shall be designed in such

a way that deposits of coating materials are minimized.

4.5 Stationary equipment shall be designed and constructed to satisfy the intended function as

given by the limitations of the manufacturer safely even in case of varying environmental conditions,

influence of external voltages, exposure to humidity, vibrations, contaminations as well as other

environmental influences. Stationary equipment shall be suitable for the intended mechanical and

thermal demands and shall withstand the effects of present or predictable aggressive materials.

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4.6 Spraying systems of category 2 shall have at least IP-protection IP64 according to EN 60529

and spraying systems of category 3 at least IP-protection IP54 according to EN 60529.

4.7 Safety devices shall function independently of the measuring, control and regulation devices

required for operation. The failure of a safety device shall be detected, if possible, by appropriate

technical measures in an adequate period so that hazardous conditions are not likely to occur.

Fundamentally the fail-safe principle shall be applied.

In case of a failure of safety devices the stationary equipment shall be led to a safe condition as far as

possible.

4.8 If the safety functions of the safety devices of the stationary equipment according to Clause 5

and Table 2 depend on software, particular attention shall be paid to the risks due to program errors.

This requirement is satisfied by observance of the requirements for the safety integrity level 2

according to EN 62061.
5 Requirements for the equipment
5.1 Electrostatic spraying systems

Depending on the maximal discharge energy that can occur, electrostatic spraying systems are

categorised in four types according to Table 1.
Table 1 – Electrostatic spraying systems for ignitable and hard to ignite
liquid coating materials – Fields of application
Types Discharge energy Hazard by Hazard
(“L” for liquid ignitable discharge by
coating during processing electric shock
materials)
Ignitable coating Hard to ignite
material coating material
(see 3.7) (see 3.8)
Type A-L < 0,24 mJ No No No
Type B-L < 350 mJ Yes No No
Type C-L < 2 J Yes No Yes
Type D-L > 2 J Yes Yes Yes

NOTE 1 The discharge energy W can be calculated by the following formula: W = ½ C · U². If resistors, semiconductors or

liquid conductors are present the calculation of W leads to a too high value, Alternatively, the discharge energy can be

determined by experiments.

NOTE 2 Hazards listed in the table are adequately prevented by observing this standard.

5.2 Requirements for spraying systems of category 3
The requirements related to the different types are listed in Table 2.
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Table 2 – Requirements for electrostatic spraying systems of category 3 for ignitable

and hard to ignite liquid coating materials
Subclause Requirements Type A-L Type B-L Type C-L Type D-L
a a
5.2.1 Distance workpiece-spraying system No Yes Yes Yes
5.2.2 Disconnection of high voltage No Yes Yes Yes
5.5.2 Protection against contact No No Yes Yes
5.2.3 Personal protection No No Yes Yes
5.2.4 Ignition protection/cleaning agent Yes Yes Yes Yes
a a
5.2.5 Locally acting fire extinguishing No Yes Yes Yes
equipment

Not required if only hard to ignite liquid coating materials are processed (see 3.8).

Satisfied by construction.

A locally acting fire extinguishing equipment is not required when using category 2G equipment of types B-L, C-L and D-L

only in areas classified as zone 2.
5.2.1 Distance workpiece – spraying system

The distance between the workpieces and the parts of the spraying system under high voltage shall be

so great that an electrical discharge is prevented during normal operation.
5.2.2 Safe disconnection of high voltage

A device shall be installed which prevents the occurrence of discharges between parts under high

voltage and earthed parts in such a way that it disconnects the high voltage, discharges the spraying

system and shuts down the supply of coating materials. In this context, a difference shall be made

between voltage-controlled, constant voltage and constant current operating modes.

For category 3 devices, this requirement is considered to be satisfied if the safe disconnection is

actuated after the first discharge at the latest. However, during normal operation spark discharges shall

not occur.
5.2.2.1 Voltage-controlled and constant voltage operating mode

A device shall be installed, which is to disconnect the high voltage, in case the safety distance between

the parts under high voltage and earthed parts drops below the permissible limit.

For voltage-controlled and constant voltage operating mode this is achieved by disconnection in case

of overcurrent I .

The disconnection threshold shall be defined with consideration of the operational and local conditions.

NOTE 1 In general, an overcurrent I , for operational currents of less than 200 µA up to 200 % or for operational currents of

more that 200 µA up to 50 % is permissible.

NOTE 2 If the disconnection threshold I value is set too high, the safe disconnection of the high voltage in case the safety

distance drops below the permissible limit and the breakthrough distance between parts under high voltage and earthed parts

of the plant is not ensured any more. This should
...