SIST EN 12957:2002

SLOVENSKI STANDARD
01-januar-2002
Machine tools - Safety - Electro discharge machines
Machine tools - Safety - Electro Discharge Machines
Werkzeugmaschinen - Sicherheit - Funkenerodiermaschinen
Machines-outils - Sécurité - Machines d'électro-érosion
Ta slovenski standard je istoveten z: EN 12957:2001
ICS:
25.120.40 Elektrokemijski stroji Electrochemical machines
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 12957
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2001
ICS 25.120.40
English version
Machine tools - Safety - Electro Discharge Machines
Machines-outils - Sécurité - Machines d'électro-érosion Werkzeugmaschinen - Sicherheit -
Funkenerodiermaschinen
This European Standard was approved by CEN on 9 May 2001.
CEN 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 Management Centre or to any CEN 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 CEN member into its own language and notified to the Management Centre has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,
Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2001 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 12957:2001 E
worldwide for CEN national Members.

Contents page
Foreword.2
0 Introduction .3
1 Scope.3
2 Normative references .3
3 Terms and definitions .5
4 List of hazards.7
5 Safety requirements and/or measures.10
5.1 General requirements .10
5.2 Operating modes .10
5.3 Stop functions .11
5.4 Safety related parts of control systems for EDM equipment or EDM systems .12
5.5 Specific requirements .12
6 Verification of safety requirements and/or measures .21
7 Information for use.21
7.1 General .21
7.2 Markings, signs, written warnings.21
7.3 Instruction handbook .21
Annex A (informative) Examples and schematic pictures .24
Annex B (normative) Noise emission measurements.33
Annex ZA (informative) Clauses of this European Standard addressing essential requirements or other
provisions of EU Directives.34
Foreword
This European Standard has been prepared by Technical Committee CEN/TC 143 "Machine tools - Safety",
the secretariat of which is held by SNV.
This European Standard shall be given the status of a national standard, either by publication of an identical
text or by endorsement, at the latest by January 2002, and conflicting national standards shall be withdrawn
at the latest by January 2002.
This European Standard has been prepared under a mandate given to CEN by the European Commission
and the European Free Trade Association, and supports essential requirements of EU Directive(s).
Annexes A and ZA of this standard are informative, Annex B is normative.
For relationship with EC Directives, see informative Annex ZA, which is an integral part of this standard.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark,
Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal,
Spain, Sweden, Switzerland and the United Kingdom.
0 Introduction
This standard applies to equipment using the process of Electro Discharge Machining (EDM) as defined in
clause 3. This European Standard is a type C Standard as stated in EN 1070.
The machinery concerned and the extent to which hazards, hazardous situations and events are covered are
indicated in the scope of this standard.
Complementary guidance is given in type A and B Standards to which reference is made in the text.
When provisions of this type C Standard are different from those which are stated in type A or B Standards,
the provisions of this type C Standard take precedence over the provisions of the other standards, for
machines that have been designed and built according to the provisions of this type C Standard. It provides
one means of conforming with the Essential Health and Safety Requirements (EHSR’s) of the "Machinery
Directive" (98/37/EC).
1 Scope
1.1 This standard specifies technical safety requirements and measures, applicable to EDM equipment
and EDM system (e.g. for spark erosion-sinking, spark erosion-wire cutting), to be adopted by persons
undertaking the design, construction, installation and/or supply of such equipment. This standard also
includes information to be provided by the manufacturer to the user.
1.2 The design requirements of this standard shall not apply to arc eroding and electro chemical
machining equipment.
1.3 This standard takes account of the intended use in normal workshop environment and non
explosive atmospheres including installation, setting, maintenance, repair and dismantling for removal or
disposal of EDM equipment.
1.4 This standard also applies to auxiliary devices essential for EDM processing.
1.5 This standard deals with specific hazards defined in clause 4, Table 1, and the measures of
prevention in clause 5, Table 2.
1.6 This standard applies to machines built after its date of issue.
NOTE Directive 94/9/EC concerning equipment and protective systems intended for use in potentially
explosive atmospheres can be applicable to the type of machine or equipment covered by this European
Standard. The present standard is not intended to provide means of complying with the essential health and
safety requirements of Directive 94/9/EC.
2 Normative references
This European Standard contains dated or not dated references on provisions from other publications. These
normative references are cited at the appropriate places in the text and the publications are listed hereafter.
For dated references, subsequent amendments to or revisions of any of these publications apply to this
European Standard only when incorporated in it by amendment or revision. For undated references the latest
edition of the publication referred to applies (including amendments).
EN 2:1992 Classification of fires
EN 54-1:1996 Fire detection and fire alarm systems - Part 1: Introduction
EN 292-1:1991 Safety of machinery - Basic concepts, general principles for design - Part 1:
Basic terminology, methodology
EN 292-2:1991 Safety of machinery - Basic concepts, general principles for design - Part 2:
Technical principles and specifications
EN 292-2:1991/A1:1995 Safety of machinery - Basic concepts, general principles for design - Part 2:
Technical principles and specifications, (Amendment A.1)
EN 294:1992 Safety of machinery - Safety distances to prevent danger zones being
reached by the upper limbs
EN 349:1993 Safety of machinery - Minimum gaps to avoid crushing of parts of the human
body
EN 418:1992 Safety of machinery - Emergency stop equipment, functional aspects -
Principles for design
EN 626-1:1994 Safety of machinery - Reduction of risks to health from hazardous
substances emitted by machinery - Part 1: Principles and specifications for
machinery manufacturers
EN 775:1992 Manipulating industrial robots - Safety (ISO 10218:1992 modified)
EN 811:1996 Safety of machinery - Safety distances to prevent danger zones being
reached by the lower limbs
EN 953:1997 Safety of machinery - Guards - General requirements for the design and
construction of fixed and movable guards
EN 954-1:1996 Safety of machinery - Safety related parts of control systems - Part 1:
General principles for design
EN 982:1996 Safety of machinery - Safety requirements for fluid power systems and their
components - Hydraulics
EN 983:1996 Safety of machinery - Safety requirements for fluid power systems and their
components - Pneumatics
EN 999:1998 Safety of machinery - The positioning of protective equipment in respect of
approach speeds of parts of the human body
EN 1037:1995 Safety of machinery - Prevention of unexpected start-up
EN 1050:1996 Safety of machinery - Principles for risk assessment
EN 1070:1998 Safety of machinery - Terminology
EN 1088:1995 Safety of machinery - Interlocking devices associated with guards - Principles
for design and selection
prEN 12437-1:1996 Safety of machinery - Permanent means of access to machines and
industrial plants - Part 1: Choice of a fixed means of access between two
levels
prEN 12437-2:1996 Safety of machinery - Permanent means of access to machines and
industrial plants - Part 2: Working platforms and gangways
prEN 12437-3:1996 Safety of machinery - Permanent means of access to machines and
industrial plants - Part 3: Stairways, stepladders and guard-rails
prEN 12437-4:1996 Safety of machinery - Permanent means of access to machines and
industrial plants - Part 4: Fixed ladders
EN 55011:1998 Industrial, scientific and medical (ISM) radio frequency equipment - Radio
disturbance characteristics - Limits and methods of measurement (CISPR
11:1997, modified)
EN 60204-1:1997 Safety of machinery - Electrical equipment of machines - Part 1: General
requirements (IEC 60204-1:1997)
EN 60529:1991 Degrees of protection provided by enclosures (IP code) (IEC 60529:1989)
EN 60742:1995 Isolating transformers and safety isolating transformers - Requirements (IEC
60742:1983 + A1:1992, modified)
EN 61000-6-2:1999 Electromagnetic compatibility (EMC) Part 6-2:Generic standards - Immunity
for industrial environments (IEC 61000-6-2:1999)
EN 61310-1:1995 Safety of machinery - Indication, marking and actuation - Part 1:
Requirements for visual, auditory and tactile signals (IEC 61310-1:1995)
EN 61310-2:1995 Safety of machinery - Indication, marking and actuation - Part 2:
Requirements for marking (IEC 61310-2:1995)
EN ISO 3746: 1995 Acoustics – Determination of sound power levels of noise sources using
sound pressure - Survey method using an enveloping measurement surface
over a reflecting plane (ISO 3746:1995)
EN ISO 4871: 1996 Acoustics – Declaration and verification of noise emission values of
machinery and equipment
EN ISO 11202:1995 Acoustics - Noise emitted by machinery and equipment - Measurement
method of emission sound pressure levels at the workstation and at other
specified positions - Survey method in situ
EN ISO 11688-1:1998 Acoustics – Recommended practice for the design of low noise machinery
and equipment – Part 1 Planning
3 Terms and definitions
For the purposes of this standard, the definitions given in EN 1070:1998 apply together with definitions listed
below.
Other general definitions (e.g. hazard, risk, safeguarding) are mentioned in corresponding type A and type B
Standards and in the annex A of EN 292-2:1991.
3.1
arc erosion; arc eroding; arc machining
the removal of material by constant (non pulsed) electro discharges, performed in a dielectric medium. The
discharges are initiated by periodical contact of the electrode with the work piece interrupted by axial
movement of the electrode
3.2
arc erosion equipment
all the necessary units for the process of arc machining
3.3
automatic mode
use of the machine under numerical control to achieve programmed sequential operation. This term is
equivalent with machining mode
3.4
control circuit
circuit used for the operational control of the machine and for protection of the power circuits
3.5
control system for EDM equipment or EDM system
the system from the initial actuator or sensor to the point of input to the final actuator or element (e.g. motor,
cylinders)
3.6
dielectric fluid (for EDM processes)
non-conductive medium to improve the discharge effect, evacuate debris and to cool the work
piece/electrode
...