SIST EN 50177:2010
(Main)Stationary electrostatic application equipment for ignitable coating powder - Safety requirements
Stationary electrostatic application equipment for ignitable coating powder - Safety requirements
This European Standard specifies the requirements for stationary electrostatic application equipment for ignitable coating powders 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. The charging of ignitable coating powder can be achieved by applying high voltage or triboelectrically. This European Standard also specifies the design-related requirements for a safe operation of the stationary equipment including its electrical installation. This European Standard considers three types of electrostatic spraying systems; see 5.1 for more details. 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. This stationary equipment is classified as equipment of group II, category 2D or category 3D for use in potentially explosive areas of zone 21 or 22, respectively.
Stationäre Ausrüstung zum elektrostatischen Beschichten mit entzünbaren Beschichtungspulvern - Sicherheitsanforderungen
Matériels fixes de projection électrostatique de poudres de revêtement inflammables - Exigences de sécurité
Vgrajena oprema za elektrostatični nanos vnetljivega prahu za prevleke - Varnostne zahteve
Ta evropski standard opredeljuje zahteve za vgrajeno opremo za elektrostatični nanos gorljivega prahu za prevleke za uporabo v eksplozivnih atmosferah, ustvarjenih z njegovim lastnim oblakom razpršila. Razlikujemo med razpršilnimi sistemi, ki ustrezajo EN 50050:2001, in razpršilnimi sistemi, oblikovanimi za višje pretočne energije in/ali tokove. Do vžiga gorljivega prahu za prevleke lahko pride z uporabo visoke napetosti ali na triboelektrični način. Ta evropski standard prav tako opredeljuje oblikovne zahteve za varno delovanje vgrajene opreme, vključno z njeno električno napeljavo. Ta evropski standard upošteva tri tipe elektrostatičnih razpršilnih sistemov; za več podrobnosti glej točko 5.1. Ta evropski standard obravnava vse nevarnosti, značilne za elektrostatično razprševanje prevlek, ki lahko vsebuje 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. Ta vgrajena oprema je razvrščena kot oprema skupine II, kategorije 2D ali kategorije 3D za uporabo na potencialno eksplozivnih območjih cone 21 oziroma 22.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 50177:2010
01-januar-2010
1DGRPHãþD
SIST EN 50177:2007
9JUDMHQDRSUHPD]DHOHNWURVWDWLþQLQDQRVYQHWOMLYHJDSUDKX]DSUHYOHNH
9DUQRVWQH]DKWHYH
Stationary electrostatic application equipment for ignitable coating powder - Safety
requirements
Stationäre Ausrüstung zum elektrostatischen Beschichten mit entzünbaren
Beschichtungspulvern - Sicherheitsanforderungen
Matériels fixes de projection électrostatique de poudres de revêtement inflammables -
Exigences de sécurité
Ta slovenski standard je istoveten z: EN 50177:2009
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 50177:2010 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN 50177:2010
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SIST EN 50177:2010
EUROPEAN STANDARD
EN 50177
NORME EUROPÉENNE
October 2009
EUROPÄISCHE NORM
ICS 87.100 Supersedes EN 50177:2006 + corr. Oct. 2007
English version
Stationary electrostatic application equipment
for ignitable coating powders -
Safety requirements
Matériels stationnaires de projection Stationäre Ausrüstung
électrostatique de poudres zum elektrostatischen Beschichten
de revêtement inflammables - mit entzünbaren Beschichtungspulvern -
Exigences de sécurité 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 50177:2009 E
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SIST EN 50177:2010
EN 50177:2009 – 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 50177 on
2009-09-01.
This European Standard supersedes EN 50177:2006 + corrigendum October 2007.
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 50177 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 50177:2006”.
___________
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Contents
0 Introduction .4
0.1 Process .4
0.2 Explosion hazards .4
0.3 Electric hazards .4
1 Scope .6
2 Normative references .6
3 Definitions .7
4 General requirements .10
5 Requirements for the equipment .11
5.1 Electrostatic spraying systems .11
5.2 Requirements for spraying systems of category 3D .11
5.3 Special requirements for spraying systems of category 2D .13
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 .15
6.3 Specific test requirements for spraying systems of type B-P, type C-P category 2D .16
7 Information for use .17
7.1 General.17
7.2 Instruction manual .18
7.3 Marking .19
7.4 Warning sign .21
Bibliography .22
Annex ZY (informative) Significant changes between this European Standard and
EN 50177:2006 .23
Annex ZZ (informative) Coverage of Essential Requirements of EC Directives .24
Figures
Figure 1 – Test assembly according to 6.3.2 .17
Tables
Table 1 – Electrostatic spraying systems for ignitable coating powders – Fields of application .11
Table 2 – Requirements for electrostatic spraying systems of category 3D for ignitable coating
powders .11
Table 3 – Survey of tests .15
Table 4 – Test intervals .19
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SIST EN 50177:2010
EN 50177:2009 – 4 –
0 Introduction
0.1 Process
During the electrostatic coating process the coating powder is transported in an air stream from a
powder hopper up to an electrostatic spraying device. As the powder particles flow through the
spraying device they are electrostatically charged by means of a high voltage of the order of some tens
of kilovolts and ejected in the form of a cloud which is directed towards the workpiece. The charged
particles of the cloud are attracted by and applied to the earthed workpiece.
Powder, that is not applied to the workpiece (overspray) is removed by a suction device or other means
in the powder collection unit.
After the coating process the workpieces are introduced into an oven where the powder is melted and
cured into a coherent coating.
0.2 Explosion hazards
An explosion could occur, if
– the concentration of coating powder in air is within the explosion limits,
– an ignition source of appropriate energy for this coating powder cloud 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 coating powder in air.
0.2.1 Mixtures of ignitable coating powder and air could only explode within a given range of
concentration, but not, if the concentration is above or below this range.
NOTE 1 If an explosive cloud of coating powder and air is trapped into a closed room, an explosion could lead to a fatal
increase of pressure.
NOTE 2 The particle size distribution of coating powders is usually in the range of 5 µm to 120 µm.
0.2.2 It is important that deposits of powder are not allowed to accumulate within the spraying areas
for they may be whirled up and give rise to an explosive atmosphere. This does not apply to deposits
on filter devices and accumulations of coating powder in hoppers where filters and hoppers are
integrated in the spraying area and are designed to collect the coating powder. [See EN 12981:2005,
4.6].
0.2.3 Particular attention should be paid to the prevention of electrostatic charges on different
surfaces, which are in the vicinity of the powder cloud. This could apply to workpieces during the
coating process or the reciprocating devices and the mounting parts of the powder 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.
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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 the 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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EN 50177:2009 – 6 –
1 Scope
1.1 This European Standard specifies the requirements for stationary electrostatic application
equipment for ignitable coating powders 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. The charging of ignitable
coating powder can be achieved by applying high voltage or triboelectrically.
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 three 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 2D or category 3D
for use in potentially explosive areas of zone 21 or 22, respectively.
NOTE For other safety aspects like
– zone classification of the areas in and around spray booths, see EN 12981:2005, 5.6.2.3;
– zone classification of other areas with explosive atmosphere, see EN 60079-10-2;
– selection, erection and application of other electrical and non electrical equipment in areas with explosion hazard, see
EN 60079-14 and EN 12981:2005, 5.6.2.4;
– health protection (for instance, noise) see also EN 12981:2005, 5.4 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 12981:2005, 5.6;
– explosion protection system, see EN 12981:2005, 5.6.2.5;
– dust hazards, see EN 12981:2005, 5.5.
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 incorporated 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 12981:2005, Coating plants - Spray booths for application of organic powder coating material - Safety
requirements
EN 13463-1, Non-electrical equipment for use in potentially explosive atmospheres – Part 1: Basic
method and requirements
EN 13478:2001, Safety of machinery – Fire prevention and protection
EN 50050:2001, Electrical apparatus for potentially explosive atmospheres – Electrostatic hand-held
spraying equipment
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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 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 coating powders
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:
– powder spray booth;
– spraying area;
– spraying system;
– dosing device;
– fixtures for workpieces;
– conveyors;
– grounding system;
– forced ventilation;
– fire prevention and protection equipment
3.2
spraying system
devices for application of coating powder by means of electrostatic charge.
In general, the spraying system consists of the following components:
– device for the supply of coating material;
– high voltage electrode;
– high voltage supply system;
– spraying device
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
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3.4
spraying area
area, closed or not, in which the coating powder 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
dosing device
in general, the dosing devices comprise the following components:
– devices for dosing the coating powder;
– supply lines for coating powder;
– devices for drive, control and monitoring powder delivery
3.7
workpiece
article to which the coating powder is applied
3.8
ignitable coating powder
coating powder which, in whirled-up state, could be ignited by an effective ignition source and which
continues to burn after the ignition source has been removed or may react in the form of an explosion
3.9
explosive atmosphere
mixture of air, under atmospheric conditions, and of 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 powder in air
mass of the ignitable coating powder applied in the spraying area divided by the volume of air
exchanged during the same period of time in the spraying area
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 of an incentive discharge [see EN 1149-5]
NOTE A necessary electric insulating resistance to prevent electric shocks is not contradictory to this definition.
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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
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 .
k
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 .
v
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 .
k
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 .
b
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 Iü.
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
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EN 50177:2009 – 10 –
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 the spraying system and workpiece and is
actuated immediately in case of fire. It shall meet the special requirements of electrostatic powder 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.
4.6 Spraying systems of category 2D, with exception of the spraying device, shall have at last IP-
protection IP64 according to EN 60529:1991 and spraying systems of category 3D, with exception of
the spraying device, shall have at last IP-protection IP54 according to EN 60529:1991.
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 risks due to program errors.
This requirement is satisfied by observance of the requirements for the safety integrity level 2
according to EN 62061.
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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 three types according to Table 1.
Table 1 – Electrostatic spraying systems for ignitable coating powders – Fields of application
Types Discharge energy Hazard by Hazard by
(“P” for powder) ignitable discharge electric shock
during processing
Type A-P < 2 mJ No No
Type B-P < 350 mJ Yes No
Type C-P > 350 mJ 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 met by observing this standard.
5.2 Requirements for spraying systems of category 3D
The requirements related to the different types are listed in Table 2.
Table 2 – Requirements for electrostatic spraying systems of category 3D
for ignitable coating powders
Subclause Requirements Type A-P Type B-P Type C-P
5.2.1 Distance workpiece-spraying system No Yes Yes
5.2.2 Disconnection of high voltage No Yes Yes
5.5.2 Protection against contact No No Yes
5.2.3 Personal protection No No Yes
b
5.2.4 Ignition protection/cleaning agent Yes Yes Yes
a
5.2.5 Locally acting fire extinguishing equipment No Yes Yes
a
A locally acting fire extinguishing equipment is not required when using category 2D equipment of types B-P and C-P only
in areas with explosion hazards of zone 22.
b
Satisfied by construction.
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 powders. In this context, a difference shall be made
between voltage-controlled, constant voltage and constant current operating modes.
For category 3D 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.
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5.2.2.1 Voltage-controlled and constant voltage operating mode
A device shall be installed, which is to disconn
...
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