1、BRITISH STANDARD BS EN 50274:2002 Low-voltage switchgear and controlgear assemblies Protection against electric shock Protection against unintentional direct contact with hazardous live parts ICS 29.130.20 Incorporating corrigendum July2009BS EN 50274:2002 ISBN 978 0 580 68600 9 Amendments/corrigend
2、a issued since publication Date Comments 31 January 2010 Implementation of CENELEC corrigendum July 2009. Text in Clause 4.5 amended National foreword This British Standard is the UK implementation of EN 50274:2002, incorporating corrigendum July 2009. The UK participation in its preparation was ent
3、rusted by Technical Committee PEL/17, Switchgear, controlgear and Hv-Lv co-ordination, to Subcommittee PEL/17/3, Low voltage switchgear and controlgear assemblies. A list of organizations represented on this subcommittee can be obtained on request to its secretary. This publication does not purport
4、to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard cannot confer immunity from legal obligations. This British Standard was published under the authority of the Standards Policy and Strategy Committee on 23 Jul
5、y 2002 BSI 2010EUROPEAN STANDARD EN 50274 NORME EUROPENNE EUROPISCHE NORM April 2002 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 1050 Brus
6、sels 2002 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 50274:2002 E ICS 29.120.60 English version Low-voltage switchgear and controlgear assemblies - Protection against electric shock - Protection against unintentional direct c
7、ontact with hazardous live parts Ensembles dappareillage basse tension - Protection contre les chocs lectriques - Protection contre le contact direct involontaire avec des parties actives dangereuses Niederspannungs- Schaltgertekombinationen - Schutz gegen elektrischen Schlag - Schutz gegen unabsich
8、tliches direktes Berhren gefhrlicher aktiver Teile This European Standard was approved by CENELEC on 2002-02-01. 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 an
9、y 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 mad
10、e 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, Czech Republic, Denmark, Finland, France, German
11、y, Greece, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.- 2 - Foreword This European Standard has been prepared by WG 3 of Technical Committee CENELEC TC 17D, Low-voltage switchgear and controlgear assemblies. It is intended
12、 as a complementary document to EN 60439-1. EN 60439-1 does not address in detail the issue of protection of skilled and instructed persons from electric shock when they are required to gain access into the assembly to manually operated devices. The intent of this standard is to provide additional r
13、equirements for the protection of these persons against electric shock. The text of the draft has been submitted to the formal vote and was approved by CENELEC as EN 50274 on 2002-02-01. The following dates were fixed: latest date by which the EN has to be implemented at national level by publicatio
14、n of an identical national standard or by endorsement (dop) 2003-02-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2005-02-01 Annexes designated “informative“ are given for information only. In this standard, annex A is informative. BS EN 50274:2002
15、 EN 50274:2002- 3 - Contents Page Introduction .4 1 Scope5 2 Normative references .5 3 Definitions.5 4 Requirements .7 4.1 General requirements.7 4.2 Positioning of operating devices.7 4.3 Measures7 4.4 Space of protection.7 4.5 Base area .7 4.6 Access area8 4.7 Equipment installed on movable parts
16、.8 5 Tests.8 5.1 Operating devices and access area .8 5.2 Finger protected and back of the hand protected locations .8 Annex A (informative) Figures for explanation .9 Figure 1 Permissible area for locating of operating devices9 Figure 2 Maximum and minimum height of the base area depending on the s
17、ervice position .10 Figure 3 Operating space for pushbutton actuation 11 Figure 4 Operating space for actuation by rotary means 12 Figure 5 Example for operating space during activation by pushbutton13 BS EN 50274:2002 EN 50274:2002- 4 - Introduction Within the European Community there are a number
18、of Directives which impact upon electrical equipment including switchgear and controlgear assemblies with regard to the health and safety of the users and others when at work. The Framework Directive (89/391/EEC) on Health and Safety sets out in article 6 - General Obligations on Employers. These in
19、clude a set of criteria to be observed. This listing is in a preferred order, and in the case of switchgear and controlgear assemblies and their operation, the intent can be summarised as follows. a) Remove the danger - in the case of assemblies where access inside for the operation of certain devic
20、es is required, this can be achieved by either isolating the assembly before entry is permitted or ensuring that the degree of protection of these devices and the accessible surrounding areas is not less than IPXXB according to EN 60529. For assemblies located in areas set apart with access restrict
21、ed to skilled and instructed persons the assembly can be isolated before access is permitted or the operating device has a degree of protection of not less than IPXXB according to EN 60529. Or if this is not possible b) Separate the person from the danger by means of screens, barriers or obstacles.
22、This standard sets out requirements according to b) for assemblies where the measures for the protection of persons as set out in a) above cannot be achieved. Or if this is not possible c) Provide personal protective equipment to ensure the health and safety of the person this is a measure of last r
23、esort and is not considered suitable for these assemblies. In addition, the requirements set out in both the Low Voltage Directive (73/23/EEC) and the use of Work Equipment Directive (89/655/EEC) together with both of their Amending Directives (93/68/EEC and 95/63/EEC) need to be observed. The parti
24、cular article of the LVD to be considered is article 2 together with clauses 1 and 2 of annex 1. Within the use of Work Equipment Directive, article 3 is particularly relevant to the design and construction of switchgear and controlgear assemblies. Controls of any description should be sited in loca
25、tions such that when they are actuated, the operator is not exposed to any danger nor risks to health. The preferred approach is to ensure that the assembly has a degree of protection not less than IPXXB at the operating faces. Alternatively, the assembly should be designed and constructed so that t
26、he controls are set apart in a safe location within the assembly where there are no hazardous live parts. It should be noted that the Basic Safety Publication (EN 61140) sets a minimum level of protection against electric shock of IPXXB for equipment. BS EN 50274:2002 EN 50274:2002- 5 - 1 Scope This
27、 standard applies to low-voltage switchgear and controlgear assemblies with a rated voltage not exceeding AC 1 000 V or DC 1 500 V. It sets out the requirements for the provision of additional features to provide protection against electric shock from direct contact with hazardous live parts only fo
28、r skilled and instructed persons when they are required to manually actuate devices within the assembly and where a level of protection for the operating face of not less than IPXXB cannot be achieved. These devices are those only accessible via a door or cover requiring a key or tool to open it or
29、in an assembly located in an area set apart and where the access to that area is restricted solely to skilled or instructed persons. This standard does not apply to manually operated devices and their locations where access is available to ordinary persons, low-voltage switchgear and controlgear ass
30、emblies where the operating voltage does not exceed AC 50 V or DC 120 V and there is protective separation, in accordance with EN 61140, between these circuits and any other circuits, NOTE Voltages generated by means of auto-transformers, potentiometers, semiconductor components etc. do NOT meet the
31、se requirements. low-voltage switchgear and controlgear assemblies where protection of persons is provided by limitation of steady-state touch current or charge in accordance with EN 61140. 2 Normative references This European Standard incorporates, by dated or undated reference, provisions from oth
32、er 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
33、 revision. For undated references, the latest edition of the publication referred to applies (including amendments). EN 60529, Degrees of protection provided by enclosures (IP Code) (IEC 60529) EN 61032, Protection of persons and equipment by enclosures Probes for verification (IEC 61032) EN 61140,
34、Protection against electric shock Common aspects for installation and equipment (IEC 61140) IEC 60050-195, International Electrotechnical Vocabulary Part 195: Earthing and protection against electric shock IEC 60050-826, International Electrotechnical Vocabulary Part 826: Electrical installations of
35、 buildings 3 Definitions For the purposes of this European Standard, the following terms and definitions apply. 3.1 low-voltage switchgear and controlgear assembly (ASSEMBLY) a combination of one or more low-voltage switching devices together with associated control, measuring, signalling, protectiv
36、e, regulating equipment, etc., completely assembled under the responsibility of the manufacturer with all internal electrical and mechanical interconnections and structural parts 3.2 hazardous live part live part which, under certain conditions, can give a harmful electric shock IEV 195-06-05 3.3 op
37、erating device actuator (e.g. pushbutton, toggle) and replaceable warning or protective device (e.g. screw plug fuse, flashing light) which serves to operate, protect or indicate the operating status of an equipment or installation BS EN 50274:2002 EN 50274:2002- 6 - 3.4 protection against unintenti
38、onal direct contact protection of skilled and/or instructed persons against unintentional direct contact of hazardous live parts NOTE Hazardous live parts are protected so as to prevent unintentional direct contact with fingers, hands, arms or other parts of the body of an operator while actuating o
39、perating devices. 3.5 space of protection space designated in an assembly where skilled and/or instructed persons can activate the operating devices without danger; defined by the base area around the operating device and by the access area in front of the operator NOTE Space of protection is shown
40、in Figure 2. 3.6 base area area limiting the operating space at the side of the operating device NOTE Base area is shown in Figure 3. 3.7 access area area limiting the operating space at the operators side NOTE Access area is shown in Figures 3, 4 and 5. 3.8 finger protection protection against acce
41、ss to hazardous live parts with a finger 3.9 back of the hand protection protection against access to hazardous live parts with the back of a hand 3.10 obstacle a part preventing unintentional direct contact, but not preventing direct contact by deliberate action IEV 826-03-14 3.11 mounting height d
42、istance between the standing area of the operator and the mid point of the actuation 3.12 operating outline envelope defined by all positions of motion and rest of the operating device 3.13 (electrically) skilled person person with relevant education and experience to enable him or her to perceive r
43、isks and to avoid hazards which electricity can create IEV 195-04-01 3.14 (electrically) instructed person person adequately advised or supervised by electrically skilled persons to enable him or her to perceive risks and to avoid hazards which electricity can create IEV 195-04-02 BS EN 50274:2002 E
44、N 50274:2002- 7 - 4 Requirements 4.1 General requirements The operating devices shall be designed and positioned in such a way that they can be reached and actuated without unintentional direct contact of hazardous live parts. 4.2 Positioning of operating devices The positioning of operating devices
45、 shall allow activation in a standing or kneeling position. The permissible area for locating of operating devices is shown in Figure 1. The permissible area for locating can be extended in exceptional cases, if a suitable safe standing area can be provided. Subject to agreement between the manufact
46、urer and user, alternative arrangements for the location of operating devices can be specified provided there is a suitable safe standing area. 4.3 Measures The required protection shall be ensured by one of the following measures, or their combination as appropriate: functional design of the equipm
47、ent to be mounted in the operating space; distances between operating devices and hazardous live parts; obstacles protected against unintentional displacement or removal. Precautions against intentional contact are not required. 4.4 Space of protection Hazardous live parts located at least partially
48、 in the operating space shall have a degree of protection of not less than IPXXA (back of the hand protected), but see 4.5. The position and the dimensions of the operating space depend on the geometrical characteristics, location and type of the operating devices as well as the service position of
49、the operator (“standing“ or “kneeling“, see Figure 2). The allocation of the base area (see Figures 3 and 4) to an operating device, depends on the type of activation and the size of the operating device. The access area depends on the service position of the operator (see Figure 2). The nominal distance between the base area and the access area is taken as 500 mm. The minimum/maximum height of the base area shall be as follows (see Figure 2): kneeling pos
