Iec 60364 4 41 2017

Part 4-41: Protection for safety – Protection against electric shock Instal ations électriques à basse tension – Partie 4-41: Protection pour assur er la sécurité – Protection contre les

Part 4-41: Protection for safety – Protection against electric shock

Instal ations électriques à basse tension –

Partie 4-41: Protection pour assur er la sécurité – Protection contre les chocs

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Part 4-41: Protection for safety – Protection against electric shock

Instal ations électriques à basse tension –

Partie 4-41: Protection pour assur er la sécurité – Protection contre les chocs

électriques

INT ERNAT IONAL

ELECT ROT ECHNICAL

ELECT ROT ECHNIQUE

INT ERNAT IONALE

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IEC 60364-4-41

Editio 5.1 2 17-0

Part 4-41: Protection for safety – Protection against electric shock

Instal ations électriques à basse tension –

Partie 4-41: Protection pour assur er la sécurité – Protection contre les chocs

®

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CONTENTS

FOREWORD 3

410 Introd ction 5

410.1 Sco e 6

410.2 Normative referen es 6

410.3 General req irements 7

41 Protective me s re: automatic dis on ection of s p ly 8

41 1 General 8

41 2 Req irements for b sic protection 8

41 3 Req irements for fault protection 9

41 4 TN s stem 1

41 5 TT s stem 1

3 41 6 IT s stem 14 41 7 Fu ctional extra-low voltage (FELV) 16 412 Protective me s re: double or reinforced in ulation 17 412.1 General 1

7 412.2 Req irements for b sic protection an fault protection 18 413 Protective me s re: electrical se aration 2

413.1 General 2

413 2 Req irements for b sic protection 2

413.3 Req irements for fault protection 2

414 Protective me s re: extra-low-voltage provided by SELV an PELV 21

414.1 General 21

414 2 Req irements for b sic protection an fault protection 21

414.3 Sources for SELV an PELV 2

414.4 Req irements for SELV an PELV circ its 2

415 Ad itional protection 2

415.1 Ad itional protection: resid al c r ent protective devices (RCDs) 2

415.2 Ad itional protection: s p lementary protective eq ip tential b ndin 2

An ex A (normative) Provision for b sic protection 2

An ex B (normative) Obstacles an placin out of re c 2

An ex C (normative) Protective me s res for a pl cation only when the in tal ation is control ed or u der the s p rvision of s i ed or in tru ted p rson 2

An ex D (informative) Cor esp n en e b twe n IEC 6 3 4-4-41:2 01 an the present stan ard

An ex D (normative) Provision where automatic dis on ection ac ordin to 41 3.2 is not fe sible 3

An ex E (informative) List of notes con ernin certain cou tries 3

Bibl ogra h 3

Fig re B.1 – Zone of arm's re c 2

Ta le 41.1 – Maximum dis onnection times 10 Ta le D.1 – Cor esp n en e b twe n IEC 6 3 4-4-41:2 01 an the present stan ard

INTERNATIONAL ELECTROTECHNICAL COMMISSION

1) Th Intern tio al Ele trote h ic l Commis io (IEC) is a worldwid org niz tio for sta d rdiz tio c mprisin

al n tio al ele trote h ic l c mmite s (IEC Natio al Commite s) Th o je t of IEC is to promote

intern tio al c -o eratio o al q e tio s c n ernin sta d rdiz tio in th ele tric l a d ele tro ic field To

this e d a d in a ditio to oth r a tivitie , IEC p bls e Intern tio al Sta d rd , Te h ic l Sp cific tio s,

Te h ic l Re orts, Pu lcly Av ia le Sp cific tio s (PAS) a d Guid s (h re fer refere to a “IEC

Pu lc tio (s)”) Th ir pre aratio is e tru te to te h ic l c mmite s; a y IEC Natio al Commite intere te

in th s bje t d alt with ma p rticip te in this pre aratory work Intern tio al g v rnme tal a d n n

-g v rnme tal org niz tio s laisin with th IEC als p rticip te in this pre aratio IEC c la orate clo ely

with th Intern tio al Org niz tio for Sta d rdiz tio (ISO) in a c rd n e with c n itio s d termin d b

a re me t b twe n th two org niz tio s

2) Th formal d cisio s or a re me ts of IEC o te h ic l maters e pre s, a n arly a p s ible, a intern tio al

c n e s s of o inio o th rele a t s bje ts sin e e c te h ic l c mmite h s re re e tatio from al

intere te IEC Natio al Commite s

3) IEC Pu lc tio s h v th form of re omme d tio s for intern tio al u e a d are a c pte b IEC Natio al

Commite s in th t s n e Whie al re s n ble eforts are ma e to e s re th t th te h ic l c nte t of IEC

Pu lc tio s is a c rate, IEC c n ot b h ld re p n ible for th wa in whic th y are u e or for a y

misinterpretatio b a y e d u er

4) In ord r to promote intern tio al u iformity, IEC Natio al Commite s u d rta e to a ply IEC Pu lc tio s

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b twe n a y IEC Pu lc tio a d th c re p n in n tio al or re io al p blc tio s al b cle rly in ic te in

th later

5) IEC its lf d e n t pro id a y ate tatio of c nformity In e e d nt c rtific tio b die pro id c nformity

a s s me t s rvic s a d, in s me are s, a c s to IEC mark of c nformity IEC is n t re p n ible for a y

s rvic s c rie o t b in e e d nt c rtific tio b die

6) Al u ers s o ld e s re th t th y h v th late t e itio of this p blc tio

7) No la i ty s al ata h to IEC or its dire tors, emplo e s, s rv nts or a e ts in lu in in ivid al e p rts a d

memb rs of its te h ic l c mmite s a d IEC Natio al Commite s for a y p rs n l injury, pro erty d ma e or

oth r d ma e of a y n ture wh ts e er, wh th r dire t or in ire t, or for c sts (in lu in le al fe s) a d

e p n e arisin o t of th p blc tio , u e of, or rela c u o , this IEC Pu lc tio or a y oth r IEC

This Con ol date version is not a of icial IEC Sta dard a d ha be n prepare for

us r c nv nie c Only the c r e t v rsion of the sta dard a d its ame dme t(s)

In this Re l ne v rsion, a v rtic l l n in th margin s ows where the te h ic l c nte t

is modifie by ame dme t 1 Addition are in gre n te t, deletions are in strik through

re te t A s parate Final v rsion with al c a g s a c pte is a ai able in this

publ c tion

International Stan ard IEC 6 3 4-4-41 has b en pre ared by IEC tec nical commite 6 :

Electrical in tal ation an protection again t electric s oc

This fif h edition con titutes a tec nical revision

The main c an es with resp ct to the previou edition are lsted b low:

– ado tion of IEC 61 4 terminology;

– layout rational zed on b sis of complete protective me s res (i.e a pro riate practical

combination of protective provision in normal service (direct contact protection) an

protective provision in case of a fault (in irect contact protection);

– req irements of 4 1 an 4 1, whic were in lu ed in the fourth edition have b en

rational zed

– dis on ection req irements for TT s stems clarified;

– IT s stems con idered more ful y;

– req irements in certain cases for ad itional protection of soc et outlets by me n of a

3 mA RCD, where the protective me s re is automatic dis on ection of s p ly

This publ cation has b en draf ed in ac ordan e with the ISO/IEC Directives, Part 2

It has the statu of a group safety publcation in ac ordan e with IEC Guide 10

The Part 4 series comprises the folowin p rts u der the general title Low-v lage ele ctric al

in stalato s:

Part 4-41: Protection for safety – Protection again t electric s oc

Part 4-4 : Protection for safety – Protection again t thermal efects

Part 4-4 : Protection for safety – Protection again t overc r ent

Part 4-44: Protection for safety – Protection again t voltage disturb n es an electromag etic

disturb n es

The commite has decided that the contents of the b se publcation an its amen ment wi

remain u c an ed u ti the sta i ty date in icated on the IEC we site u der

"htp:/ we store.iec.c " in the data related to the sp cific publ cation At this date, the

410 Introduction

This Part 4-41 of IEC 6 3 4 de ls with protection again t electric s oc as a pl ed to

electrical in talation It is b sed on IEC 61 4 whic is a b sic safety stan ard that a pl es

to the protection of p rson an l vestoc IEC 61 4 is inten ed to give fu damental

prin iples an req irements that are common to electrical in talation an eq ipment or are

neces ary for their co-ordination

The fu damental rule of protection again t electric s oc , ac ordin to IEC 61 4 , is that

hazardou -l ve-p rts mu t not b ac es ible an ac es ible con u tive p rts mu t not b

hazardou lve, neither u der normal con ition nor u der sin le fault con ition

Ac ordin to 4.2 of IEC 61 4 , protection u der normal con ition is provided by b sic

protective provision an protection u der sin le fault con ition is provided by fault

protective provision Alternatively, protection again t electric s oc is provided by an

en an ed protective provision, whic provides protection u der normal con ition an u der

sin le fault con ition

This stan ard has the statu of a group safety publ cation (GSP) for protection again t electric

s oc

In the fourth edition of IEC 6 3 4 (2 01):

– protection u der normal con ition (now desig ated b sic protection) was refer ed to as

protection again t direct contact an

– protection u der fault con ition (now desig ated fault protection) was refer ed to as

protection again t in irect contact

LOW-VOLTAGE ELECTRICAL INSTALLATIONS –

Part 4-41: Protection for safety –

Protection against electric shock

410.1 Sc pe

Part 4-41 of IEC 6 3 4 sp cifies es ential req irements regardin protection again t electric

s oc , in lu in b sic protection (protection again t direct contact an fault protection

(protection again t in irect contact of p rson an lvestoc It de ls also with the a plcation

an co-ordination of these req irements in relation to external influen es

Req irements are also given for the a pl cation of ad itional protection in certain cases

410.2 Normativ refere c s

The fol owin referen ed doc ments are in isp n a le for the a pl cation of this doc ment

For dated referen es, only the edition cited a pl es For u dated referen es, the latest edition

of the referen ed doc ment (in lu in an amen ments) a pl es

e rectio of electrical e qu ip me t – Wirin systems

1)

IEC 6 3 4-5-5 , Ele c tric al instalato s o f bu ildin s – Part 5-5 : Sele cto n and e re cto n o f

ele c tric le qu ip me t – Earthin arange me ts, p rote ctv co ducto rs andp rote ctv b ondin

co nducto rs

IEC 6 3 4-6, Low-v lage ele c tric l instalato s – Part 6: Verific to

2)

IEC 6 4 9, Volage bands fo r ele c trical instalato s of bu ildings

IEC 6 614 (al p rts), Co du its fo r ele ctric al instalato ns – Spe c ificato

IEC 610 4 (al parts), Cable tru nkin and duc tin systems fo r ele c tric l instalato s

IEC 61 4 , Pro te cto n a gainst electric sho ck – Co mmo n a sp e cts fo r in stalato ande quip m e nt

IEC 613 6 (al parts), Co du it systems for ele c tric al instalato s

IEC 615 8-2-6, Safety of p wer transfo rmers, p wer supply u nis and simiar – Part 2-6:

Partc u lar re qu ire me ts fo r s fety isolatn transforme rs for g ne ral use

IEC Guide 10 , Th p re arato of s fe ty publcato ns and th use o f ba ic s fety pub lic ato ns

and group s fe ty pu b licato ns

410.3 Ge eral re uireme ts

410.3.1 In this stan ard the folowin sp cification of voltages is inten ed u les otherwise

stated:

– a.c voltages are r.m.s

– d.c voltages are rip le- re

Rip le- re is con entional y defined as an r.m.s rip le voltage of not more than 10 % of the

d.c comp nent

410.3.2 A protective me s re s al con ist of

– an a pro riate combination of a provision for b sic protection an an in e en ent

provision for fault protection, or

– an en an ed protective provision whic provides b th b sic protection an fault

protection

Ad itional protection is sp cified as p rt of a protective me s re u der certain con ition of

external influen es an in certain sp cial location (se the cor esp n in Part 7 of

IEC 6 3 4)

NOT 1 For s e ial a plc tio s, prote tiv me s re whic d n t folow this c n e t are p rmite (s e 410.3.5

a d 410.3.6)

NOT 2 An e ample of a e h n e prote tiv me s re is reinforc d in ulatio

410.3.3 In e c p rt of an in tal ation one or more protective me s res s al b a pl ed,

takin ac ou t of the con ition of external influen e

The fol owin protective me s res general y are p rmited:

– automatic dis on ection of s p ly (Clau e 41 ),

– double or reinforced in ulation (Clau e 412),

– electrical se aration for the s p ly of one item of c r ent u in eq ipment (Clau e 413),

– extra-low-voltage (SELV an PELV) (Clau e 414)

The protective me s res a pl ed in the in tal ation s al b con idered in the selection an

erection of eq ipment

For p rtic lar in tal ation se 410.3.4 to 410.3.9

NOT In ele tric l in talatio s th mo t c mmo ly u e prote tiv me s re is a tomatic dis o n ctio of s p ly

410.3.4 For sp cial in tal ation or location , the p rtic lar protective me s res in the

cor esp n in Part 7 of IEC 6 3 4 s al be a pl ed

410.3.5 The protective me s res, sp cified in An ex B, i.e the u e of o stacles an placin

out of re c , s al only b u ed in in tal ation ac es ible to

– s i ed or in tru ted p rson , or

– p rson u der the s p rvision of s i ed or in tru ted p rson

410.3.6 The protective me s res, sp cified in An ex C, i.e

– e rth- re local eq ip tential b n in ,

– electrical se aration for the s p ly of more than one item of c r ent u in eq ipment,

may b a pl ed only when the in tal ation is u der the s p rvision of s i ed or in tru ted

p rson so that u authorized c an es can ot b made

410.3.7 If certain con ition of a protective me s re can ot b met, s p lementary

provision s al b a pl ed so that the protective provision together ac ieve the same degre

of safety

NOT An e ample of th a plc tio of this rule is giv n in 41 7

410.3.8 Diferent protective me s res a pled to the same in talation or p rt of an

in tal ation or within eq ipment s al have no influen e on e c other s c that faiure of one

protective me s re could imp ir the other protective me s res

410.3.9 The provision for fault protection (protection again t in irect contact may b omit ed

for the fol owin eq ipment:

– metal s p orts of overhe d l ne in ulators whic are at ac ed to the bui din an are

placed out of arm’s re c ;

– ste l reinforced con rete p les of overhe d l nes in whic the ste l reinforcement is not

ac es ible;

– exp sed-con u tive-p rts whic , owin to their red ced dimen ion (a proximately

5 mm x 5 mm) or their disp sition can ot b grip ed or come into sig ificant contact

with a p rt of the h man b d an provided that con ection with a protective con u tor

could only b made with dif ic lty or would b u rela le

NOT 1 This e emptio a ple , for e ample, to b lts, riv ts, n me late a d c ble clp

NOT 2 In th USA, al e p s d-c n u tiv -p rts are b n e to th prote tiv c n u tor

– metal tub s or other metal en los res protectin eq ipment in ac ordan e with

Clau e 412

411 Prote tiv me sure: automatic disconne tion of supply

41 1 Ge eral

Automatic dis on ection of s p ly is a protective me s re in whic

– b sic protection is provided by b sic in ulation of l ve p rts or by b r iers or en los res, in

ac ordan e with Annex A, an

– fault protection is provided by protective eq ip tential b n in an automatic

dis on ection in case of a fault in ac ordan e with 41 3 to 41 6

NOT 1 Wh re this prote tiv me s re is a ple , Cla s I e uipme t ma als b u e

Where sp cified, ad itional protection is provided by a resid al c r ent protective device

(RCD) with rated resid al o eratin c r ent not ex e din 3 mA in ac ordan e with 415.1

NOT 2 Re id al c re t mo itors (RCMs) are n t prote tiv d vic s b t th y ma b u e to mo itor re id al

c re ts in ele tric l in talatio s R Ms pro u e a a dible or a dible a d vis al sig al wh n a pre ele te v lu

of re id al c re t is e c e e

41 2 Re uireme ts for ba ic prote tio

Al electrical eq ipment s al comply with one of the provision for b sic protection (protection

again t direct contact des rib d in An ex A or, where a pro riate, An ex B

41 3 Re uireme ts for fa lt prote tion

41 3.1 Prote tiv e rthing a d prote tiv e uipote tial bonding

41 3.1.1 Prote tiv e rthing

Exp sed-con u tive-p rts s al b con ected to a protective con u tor u der the sp cific

con ition for e c typ of s stem e rthin as sp cified in 41 4 to 41 6

Simultane u ly ac es ible exp sed-con u tive-p rts s al b con ected to the same e rthin

s stem in ivid al y, in groups or col ectively

Con u tors for protective e rthin s al comply with IEC 6 3 4-5-5

Eac circ it s al have avai a le a protective con u tor con ected to the relevant e rthing

terminal

41 3.1.2 Prote tiv e uipote tial bonding

In e c buidin , the e rthin con u tor, the main earthin terminal an the fol owin

• metal c pip s s p lyin services into the bui din , for example gas, water, district he tin

Where s c cond ctive p rts originate outside the bui din , they s al b b n ed as close as

practica le to their p int of entry within the bui din

41 3.2 Automatic dis o ne tion in c s of a fa lt

automatical y inter upt switc of the s p ly to the l ne con u tor of a circ it or eq ipment in

the event of a fault of negl gible imp dan e b twe n the l ne con u tor an an exp sed

-con u tive-p rt or a protective con u tor in the circ it or eq ipment within the dis on ection

time req ired in 41 3.2.2, 41 3.2.3 or 41 3.2.4

rele a t Part 7 of IEC 6 3 4.

NOT For IT s stems, a tomatic dis o n ctio is n t u u ly n c s ariy re uire o th o c re c of a first

fa lt (s e 41 6.1) For th re uireme ts for dis o n ctio afer th first fa lt s e 41 6.4 in th e e t of a s c n

41 3.2.2 The maximum dis on ection time stated in Ta le 41.1 s al b a pl ed to final

Wh re in T s stems th dis o n ctio is a hie e b a o erc r e t prote tiv d vic a d th prote tiv

e uip te tial b n in is c n e te with al e tra e u -c n u tiv -p rts within th in talatio , th ma imum

dis o n ctio time a plc ble to TN s stems ma b u e

Dis o n ctio ma b re uire for re s n oth r th n prote tio a ain t ele tric s o k

o

41 3.2.3 In TN s stems, a dis on ection time not ex e din 5 s is p rmited for distribution

circ its, an for circ its not covered by 41 3.2.2

41 3.2.4 In TT s stems, a dis on ection time not ex e din 1 s is p rmited for distribution

circ its an for circ its not covered by 41 3.2.2

41 3.2.5 For s stems with nominal voltage U

o

41 3.2.6 If automatic dis on ection ac ordin to 41 3.2.1 can ot b ac ieved in the time

req ired by 41 3.2.2, 41 3.2.3, or 41 3.2.4 as a pro riate, s p lementary protective

eq ip tential b n in s al b provided in ac ordan e with 415.2

41 3.3 Addition l prote tio Furth r re uireme ts for s c et o tlets a d for the

In a.c s stems, Ad itional protection by me n of a resid al c r ent protective device (RCD)

provided for

– a.c soc et outlets with a rated c r ent not ex e din 2 3 A that are for l a le to b u ed

by ordinary p rson an are inten ed for general u e; an

41 4 TN s stem

41 4.1 In TN s stems the integrity of the e rthin of the in tal ation de en s on the rela le

an ef ective con ection of the PEN or PE con u tors to e rth Where the e rthin is

provided from a publ c or other s p ly s stem, compl an e with the neces ary con ition

external to the in tal ation is the resp n ibi ty of the s p ly network o erator

NOT 1 Ex mple of c n itio s in lu e:

• th P N is c n e te to e rth at a n mb r of p ints a d is in tale in s c a wa a to minimiz th ris of

arisin from a bre k in th P N c n u tor;

is th minimum c nta t re ista c with e rth, in o ms, of e tra e u -c n u tiv -p rts n t c n e te to a

prote tiv c n u tor, thro g whic a fa lt b twe n ln a d e rth ma o c r;

B E o

41 4.2 The neutral p int or the midp int of the p wer s p ly s stem s al b e rthed If a

neutral p int or midp int is not avai a le or not ac es ible, a l ne con u tor s al b e rthed

Exp sed-con u tive-p rts of the in tal ation s al b con ected by a protective con u tor to

the main e rthin terminal of the in tal ation whic s al b con ected to the e rthed p int of

the p wer s p ly s stem

NOT 1 If other ef ective e rth con ection exist, it is recommen ed that the protective

con u tors also b con ected to s c p ints wherever p s ible Earthin at ad itional p ints,

distributed as evenly as p s ible, may b neces ary to en ure that the p tentials of protective

con u tors remain, in case of a fault, as ne r as p s ible to that of e rth

NOT 2 It is recommen ed that protective con u tors (PE an PEN) s ould b e rthed where

they enter an bui din s or premises takin ac ou t of an diverted neutral c r ents of

41 4.3 In fixed in tal ation , a sin le con u tor may serve b th as a protective con u tor

an as a neutral con u tor (PEN con u tor) provided that the req irements of 5 3.4 of

IEC 6 3 4-5-5 are satisfied No switc in or isolatin device s al b in erted in the PEN

con u tor

NOT 1 In Switz rla d th main b idin o erc re t prote tiv d vic with inte rate is latin d vic in th P N

c n u tor forms th interfa e b twe n th n twork a d th in talatio of th b idin

NOT 2 In Norwa , th u e of a P N c n u tor d wn tre m of th main distrib tio b ard is n t alowe

41 4.4 The c aracteristic of the protective devices (se 41 4.5) an the circ it

imp dan es s al fulfi the fol owin req irement:

– the l ne con u tor up to the p int of the fault, an

– the protective con u tor b twe n the p int of the fault an the source;

I

a

is the c r ent in amp res (A) cau in the automatic o eration of the dis on ectin device

within the time sp cified in 41 3.2.2, or 41 3.2.3 When a resid al c r ent protective

device (RCD) is u ed this c r ent is the resid al o eratin c r ent providin dis on ection

in the time sp cified in 41 3.2.2, or 41 3.2.3:

U

o

is the nominal a.c or d.c l ne to e rth voltage in volts (V)

NOT Wh re c mpla c with this s b la s is pro id d b a R D, th dis o n ctin time in a c rd n e with

41 4.5 In TN s stems, the fol owin protective devices may b u ed for fault protection

(protection again t in irect contact :

– overc r ent protective devices;

– resid al c r ent protective devices (RCDs)

NOT 1 Wh re a R D is u e for fa lt prote tio th circ it s o ld als b prote te b a o erc re t

A resid al c r ent protective device (RCD) s al not b u ed in TN-C s stems

NOT 2 Wh re dis rimin tio b twe n R Ds is n c s ary, s e 5 5.3 of IEC 6 3 4-5-5

41 5 TT s stem

41 5.1 Al exp sed-con u tive-p rts col ectively protected by the same protective device

s al b con ected by the protective con u tors to an e rth electrode common to al those

p rts Where several protective devices are uti zed in series, this req irement a pl es

se arately to al the exp sed-con u tive-p rts protected by e c device

The neutral p int or the mid-p int of the p wer s p ly s stem s al b e rthed If a neutral

p int or mid-p int is not avai a le or not ac es ible, a l ne con u tor s al b e rthed

NOT In th Neth rla d th re ista c of th e rth ele tro e s o ld b a low a pra tic ble, b t in a y c s

n t e c e in 16 Ω

41 5.2 General y in TT s stems, RCDs s al b u ed for fault protection Alternatively,

overc r ent protective devices may b u ed for fault protection provided a s ita ly low value

of Z

s

NOT 1 Wh re a R D is u e for fa lt prote tio th circ it s o ld als b prote te b a o erc re t

prote tiv d vic in a c rd n e with IEC 6 3 4-4-4

NOT 2 Th u e of fa ltv lta e o erate prote tiv d vic s is n t c v re b this sta d rd

NOT 3 In th Neth rla d wh re a e rthin s stem is u e for more th n o e ele tric l in talatio c mpla c

with 41 5.3 s al remain efe tiv in c s of

– a y sin le bre k of th e rthin s stem,

– faiure of a y re id al c re t prote tiv d vic (R D)

41 5.3 Where a resid al c r ent protective device (RCD) is u ed for fault protection, the

fol owin con ition s al b fulfi ed:

i) the dis on ection time as req ired by 41 3.2.2 or 41 3.2.4, an

is the rated resid al o eratin c r ent of the RCD

NOT 1 Fa lt prote tio is pro id d in this c s als if th fa lt imp d n e is n t n glgible

NOT 2 Wh re dis rimin tio b twe n R Ds is n c s ary s e 5 5.3 of IEC 6 3 4-5-5

NOT 3 Wh re R

A

is n t k own, it ma b re la e b Z

S

NOT 4 Th dis o n ctio time in a c rd n e with Ta le 41.1 relate to pro p ctiv re id al fa lt c r e ts

sig ific ntly hig er th n th rate re id al o eratin c re t of th RC (ty ic ly 5 I

∆n)

41 5.4 Where an over-c r ent protective device is u ed the fol owin con ition s al b

− the source,

− the l ne con u tor up to the p int of the fault,

− the protective con u tor of the exp sed-con u tive-p rts,

− the e rth electrode of the in tal ation an

− the e rth electrode of the source;

41 6.1 In IT s stems l ve p rts s al b in ulated from e rth or con ected to e rth throu h

a s f iciently hig imp dan e This con ection may b made either at the neutral p int or mi

d-p int of the s stem or at an artificial neutral p int The lat er may b con ected directly to

e rth if the res ltin imp dan e to e rth is s f iciently hig at the s stem freq en y Where

no neutral p int or mid-p int exists, a l ne con u tor may b con ected to e rth throu h a

hig imp dan e

The fault c r ent is then low in the event of a sin le fault to an exp sed-con u tive-p rt or to

e rth an automatic dis onnection in ac ordan e with 41 3.2 is not imp rative provided the

con ition in 41 6.2 is fulfi ed Provision s al b taken, however, to avoid ris of harmful

p tho h siological ef ects on a p rson in contact with simultaneou ly ac es ible exp sed

-con u tive-p rts in the event of two faults existin simultane u ly

NOT 1 To re u e o erv lta e or to d mp v lta e o ci atio , it ma b n c s ary to pro id e rthin thro g

imp d n e or artificial n utral p ints, a d th c ara teristic of th s s o ld b a pro riate to th re uireme ts

of th in talatio

NOT 2 In Norwa , wh re more in talatio s are lk ly to h v g lv nic c n e tio to th s me distrib tio

n twork, al fin l circ its in IT in talatio s with g lv nic c n e tio to a p blc IT distrib tio n twork n e to b

dis o n cte within th time s e ifie for a TN s stem (s e Ta le 41.1) in th e e t of a fa lt of n glgible

imp d n e b twe n th ln c n u tor a d a e p s d-c n u tiv -p rt or a prote tiv c n u tor in th circ it or

e uipme t

41 6.2 Exp sed-con u tive-p rts s al b e rthed in ivid al y, in groups, or col ectively

The fol owin con ition s al b fulfi ed:

In a.c s stems the fol owin con ition s al b fulfi ed to l mit the tou h voltage to:

is the s m of the resistan e in Ω of the e rth electrode an protective con u tor for the

exp sed-con u tive-p rts;

I

d

is the fault c r ent in A of the first fault of negl gible imp dan e b twe n a lne

con u tor an an exp sed-con u tive-p rt The value of I

dtakes ac ou t of le kage

c r ents an the total e rthin imp dan e of the electrical in tal ation

41 6.3 In IT s stems the fol owin monitorin devices an protective devices may b u ed:

– in ulation monitorin devices (IMDs);

– resid al c r ent monitorin devices (RCMs)

– in ulation fault location s stems (IFLS);

– overc r ent protective devices;

– resid al c r ent protective devices (RCDs)

first fa lt c n ot b e clu e d e to c p citiv le k g c re ts.

This device s al initiate an au ible an /or vis al sig al whic s al contin e as lon as the

If there are b th au ible an visible sig als, it is p rmis ible for the au ible sig al to b

can el ed

NOT 1 It is recommen ed that a first fault b el minated with the s ortest practica le delay

41 6.4 Af er the oc ur en e of a first fault, con ition for automatic dis on ection of s p ly

in the event of a secon fault oc ur in on a diferent l ve con u tor s al b as fol ows:

a) Where exp sed-con u tive-p rts are intercon ected by a protective con u tor colectively

e rthed to the same e rthin s stem, the con ition simi ar to a TN s stem a ply an the

folowin con ition s al b fulfi ed where the neutral con u tor is not distributed in a.c

s stems an in d.c s stems where the mid-p int con u tor is not distributed:

2I

aZ

s

≤ U

aZ’

is the nominal a.c or d.c voltage, in V, b twe n l ne con u tor an neutral

con u tor or mid-p int con u tor, as a pro riate;

U is the nominal a.c or d.c voltage in V b twe n l ne con u tors;

Z

s

is the imp dan e in Ω of the fault lo p comprisin the l ne con u tor an the

protective con u tor of the circ it;

Z′

s

is the imp dan e in Ω of the fault lo p comprisin the neutral con u tor an the

protective con u tor of the circ it;

I

a

is the c r ent in A cau in o eration of the protective device within the time req ired

in 41 3.2.2 for TN s stems or 41 3.2.3

NOT 1 Th time state in Ta le 41.1 of 41 3.2.2 for th TN s stem is a plc ble to IT s stems with a

distrib te or n n-distrib te n utral c n u tor or mid-p int c n u tor

NOT 2 Th fa tor 2 in b th formula ta e into a c u t th t in th e e t of th simulta e u o c re c of two

fa lts,th fa lts ma e ist in difere t circ its

is the s m of the resistan es of the e rth electrode an the protective con u tor to the

exp sed-con u tive-p rts,

I

a

is the c r ent cau in automatic dis on ection of the dis on ection device in a time

complyin to that for TT s stems in Ta le 41.1 of 41 3.2.2 or in a time complyin to

41 3.2.4

NOT 4 If c mpla c to th re uireme ts of b) is pro id d b a re id al c r e t prote tiv d vic (R D)

c mpla c with th dis o n ctio time re uire for T s stems in Ta le 41.1 ma re uire re id al c re ts

sig ific ntly hig er th n th rate re id al o eratin c re t I

∆n

of th R D a ple (ty ic ly 5 I

∆n)

41 7 Functio al e tra-low v lta e (FELV)

Where, for fu ctional re son , a nominal voltage not ex e din 5 V a.c or 12 V d.c is u ed

but al the req irements of Clau e 414 relatin to SELV or to PELV are not fulfi ed, an where

SELV or PELV is not neces ary, the s p lementary provision des rib d in 41 7.2 an

41 7.3 s al b taken to en ure b sic protection an fault protection This combination of

provision is k own as FELV

NOT Su h c n itio s ma , for e ample, b e c u tere wh n th circ it c ntain e uipme t (s c a

tra sformers, rela s, remote-c ntrol switc e , c nta tors) in uficie tly in ulate with re p ct to circ its at hig er

v lta e

41 7.2 Re uireme ts for ba ic prote tio

Basic protection s al b provided by either

– b sic in ulation ac ordin to Clau e A.1 cor esp n in to the nominal voltage of the

primary circ it of the source, or

– b r iers or en los res in ac ordan e with Clau e A.2

41 7.3 Re uireme ts for fa lt prote tion

The exp sed-con u tive-p rts of the eq ipment of the FELV circ it s al b con ected to the

protective con u tor of the primary circ it of the source, provided that the primary circ it is

s bject to protection by automatic dis on ection of s p ly des rib d in 41 3 to 41 6

The source of the FELV s stem s al b either a tran former with at le st simple se aration

b twe n win in s or s al comply with 414.3

NOT If th s stem is s p le from a hig er v lta e s stem b e uipme t whic d e n t pro id at le st simple

s p ratio b twe n th t s stem a d th F LV s stem, s c a a totra sformers, p te tiometers, s mic n u tor

d vic s, etc th o tp t circ it is d eme to b a e te sio of th in ut circ it a d s o ld b prote te b th

prote tiv me s re a ple in th in ut circ it

41 7.5 Plu s a d s c et o tlets

Plu s an soc et outlets for FELV s stems s al comply with al the folowin req irements:

– plu s s al not be a le to enter soc et outlets of other voltage s stems,

– soc et outlets s al not admit plu s of other voltage s stems, an

– soc et outlets s al have a protective con u tor contact

412 Prote tiv me sure: double or reinforce insulation

412.1.1 Double or reinforced in ulation is a protective me s re in whic

– b sic protection is provided by b sic in ulation, an fault protection is provided by

s p lementary in ulation, or

– b sic an fault protection is provided by reinforced in ulation b tween l ve p rts an

ac es ible p rts

NOT This prote tiv me s re is inte d d to pre e t th a p ara c of d n ero s v lta e o th a c s ible

p rts of ele tric l e uipme t thro g a fa lt in th b sic in ulatio

a pl ed to an circ it that in lu es a soc et outlet or where a u er may c an e items of

412.2 Re uireme ts for ba ic prote tio a d fa lt prote tion

412.2.1 Ele tric l e uipme t

Where the protective me s re, u in double or reinforced in ulation, is u ed for the complete

in tal ation or p rt of the in tal ation, electrical eq ipment s al comply with one of the

fol owin s bclau es:

– 412.2.1.1; or

– 412.2.1.2 an 412.2.2; or

– 412.2.1.3 an 412.2.2

412.2.1.1 Electrical eq ipment s al b of the fol owin typ s, an typ tested an marked to

the relevant stan ard :

– electrical eq ipment havin double or reinforced in ulation (Clas I eq ipment ;

– electrical eq ipment declared in the relevant prod ct stan ard as eq ivalent to Clas I ,

s c as as embl es of electrical eq ipment havin total in ulation (se IEC 6 4 9-1 the

412.2.1.2 Electrical eq ipment havin b sic in ulation only s al have s p lementary

in ulation a pl ed in the proces of erectin the electrical in tal ation, providin a degre of

safety eq ivalent to electrical eq ipment ac ordin to 412.2.1.1 an complyin with 412.2.2.1

to 412.2.2.3

NOT The s mb l s ould b fixed in a visible p sition on the exterior an interior of the

412.2.1.3 Electrical eq ipment havin u in ulated lve p rts s al have reinforced in ulation

a pl ed in the proces of erectin the electrical in tal ation, providin a degre of safety

eq ivalent to electrical eq ipment ac ordin to 412.2.1.1 an complyin with 412.2.2.2 an

412.2.2.3; s c in ulation b in recog ized only where con tru tional features prevent the

a pl cation of double in ulation

NOT The s mb l s ould b fixed in a visible p sition on the exterior an interior of the

412.2.2 Enclos re

412.2.2.1 The electrical eq ipment b in re d for o eration, al con u tive p rts se arated

from l ve p rts by b sic in ulation only, s al b contained in an in ulatin en los re af ordin

at le st the degre of protection IPXXB or IP2X

412.2.2.2 The fol owin req irements a ply as sp cified:

– the in ulatin en los re s al not b traversed by con u tive p rts lkely to tran mit a

p tential; an

———————

– the in ulatin en los re s al not contain an s rews or other fixin me n of in ulatin

material whic mig t ne d to b removed, or are lkely to b removed, d rin in tal ation

an maintenan e an whose re lacement by metal c s rews or other fixin me n could

imp ir the en los re’s in ulation

Where the in ulatin en los re mu t b traversed by mec anical joints or con ection (e.g

for o eratin han les of bui t in a p ratu ), these s ould b ar an ed in s c a way that

protection again t s oc in case of a fault is not imp ired

412.2.2.3 Where l d or do rs in the in ulatin en los re can b o ened without the u e of a

to l or key, al con u tive p rts whic are ac es ible if the l d or do r is o en s al b b hin

an in ulatin b r ier (providin a degre of protection not les than IPXXB or IP2X) preventin

p rson from comin u intentional y into contact with those con u tive p rts This in ulatin

b r ier s al b remova le only by u e of a to l or key

412.2.2.4 Con u tive p rts en losed in the in ulatin en los re s al not b con ected to a

protective con u tor However, provision may b made for con ectin protective con u tors

whic neces ari y ru throu h the en los re in order to serve other items of electrical

eq ipment whose s p ly circ it also ru s throu h the en los re In ide the en los re, an

s c con u tors an their terminals s al b in ulated as thou h they were l ve p rts, an

their terminals s al b marked as PE terminals

Exp sed-con u tive-p rts an intermediate p rts s al not b con ected to a protective

con u tor u les sp cific provision for this is made in the sp cification for the eq ipment

con erned

412.2.2.5 The en los re s al not ad ersely afect the o eration of the eq ipment protected

in this way

412.2.3 Instal ation

412.2.3.1 The in tal ation of eq ipment mentioned in 412.2.1 ( ixin , con ection of

con u tors, etc.) s al b ef ected in s c a way as not to imp ir the protection af orded in

compl an e with the eq ipment sp cification

412.2.3.2 Ex e t where 412.1.3 412.1.2 a pl es, a circ it s p lyin items of Clas I

eq ipment s al have a circ it protective con u tor ru to an terminated at e c p int in

wirin an at e c ac es ory

NOT This re uireme t is inte d d to ta e a c u t of th re la eme t b th u er of Cla s I e uipme t b

Cla s I e uipme t

412.2.4 Wiring s stems

412.2.4.1 Wirin s stems in tal ed in ac ordan e with IEC 6 3 4-5-5 are con idered to

me t the req irements of 412.2 if they con ist of:

than the nominal voltage of the s stem an at le st 3 0 V/ to 5 0 V, en losed in tru kin

in ulatio of th c bln s stem is at le st e uiv le t to th re uireme t in IEC 61 4 for reinforc d in ulatio

NOT 2 1 Su h wirin s stems s o ld are n t b id ntifie b th s mb l IEC 6 417-517 :2 0 -0

NOT 3 2 In Italy, wirin s stems in tale in a c rd n e with IEC 6 3 4-5-5 in ele tric l s stems with n min l

v lta e n t hig er th n 6 0 V, are c n id re to me t th re uireme ts of 412.2 if th folowin c ble or

• c ble , pro id d with a metal c s e th, h vin b twe n th c n u tors a d th metal c s e th a d b twe n

s c metal c s e th a d th e tern l s rfa e, a in ulatio a e u te for th n min l v lta e of th ele tric l

s stem

413 Prote tiv me sure: ele trical separation

413.1 Ge eral

413.1.1 Electrical se aration is a protective me s re in whic

– b sic protection is provided by b sic in ulation of l ve p rts or by b r iers an en los res

NOT Wh n this prote tiv me s re is u e , it is p rtic larly imp rta t to e s re c mpla c of th b sic

in ulatio with th pro u t sta d rd

413.1.3 Where more than one item of c r ent u in eq ipment is s p l ed from an u e rthed

source with simple se aration, the req irements of Clau e C.3 s al b met

413.3.2 The se arated circ it s al b s p led throu h a source with at le st simple

se aration, an the voltage of the se arated circ it s al not ex e d 5 0 V

413.3.3 Live p rts of the se arated circ it s al not b con ected at an p int to another

circ it or to e rth or to a protective con u tor

To en ure electrical se aration, ar an ements s al b s c that b sic in ulation is ac ieved

b twe n circ its

413.3.4 Flexible ca les an cord s al b visible throu hout an p rt of their len th l a le to

mec anical damage

413.3.5 For se arated circ its the u e of se arate wirin s stems is recommen ed If

se arated circ its an other circ its are in the same wirin s stem, multi-con u tor ca les

without metal c coverin , in ulated con u tors in in ulatin con uit, in ulated d ctin or

in ulated tru kin s al b u ed, provided that

– the rated voltage is not les than the hig est nominal voltage, an

– e c circ it is protected again t overc r ent

413.3.6 The exp sed-con u tive-p rts of the se arated circ it s al not b con ected either

to the protective con u tor or exp sed-con u tive-p rts of other circ its, or to e rth

NOT If th e p s d-c n u tiv -p rts of th s p rate circ it are la le to c me into c nta t, eith r inte tio aly

or fortuito sly, with th e p s d-c n u tiv -p rts of oth r circ its, prote tio a ain t ele tric s o k n lo g r

d p n s s lely o prote tio b ele tric l s p ratio b t o th prote tiv pro isio s to whic th later e p s d

-c n u tiv -p rts are s bje t

414 Prote tiv me sure: extra-low-v ltage provide by SELV a d PELV

414.1 Ge eral

414.1.1 Protection by extra-low-voltage is a protective me s re whic con ists of either of

two dif erent extra-low-voltage s stems:

– SELV; or

This protective me s re req ires:

– l mitation of voltage in the SELV or PELV s stem to the up er lmit of voltage Ban I 5 V

a.c or 12 V d.c (se IEC 6 4 9), an

– protective se aration of the SELV or PELV s stem from al circ its other than SELV an

PELV circ its, an b sic in ulation b twe n the SELV or PELV s stem an other SELV or

PELV s stems, an

– for SELV s stems only, b sic in ulation b twe n the SELV s stem an e rth

414.1.2 The u e of SELV or PELV ac ordin to Clau e 414 is con idered as a protective

me s re in al situation

NOT In c rtain c s s th sta d rd of th IEC 6 3 4-7 s rie lmit th v lu of th e tra-low v lta e to a v lu

lower th n5 V a.c or 12 V d.c

414.2 Re uireme ts for ba ic prote tion a d fa lt prote tio

Basic protection an fault protection is de med to b provided when

– the nominal voltage can ot ex e d the up er lmit of voltage Ban I

– the s p ly is from one of the sources l sted in 414.3, an

– the con ition of 414.4 are fulfi ed

NOT 1 If th s stem is s p le from a hig er v lta e s stem b e uipme t whic pro id s at le st simple

s p ratio b twe n th t s stem a d th e tra-low-v lta e s stem, b t whic d e n t me t th re uireme ts for

S LV a d P LV s urc s in 414.3,th re uireme ts for F LV ma b a plc ble, s e 41 7

NOT 2 D v lta e for ELV circ its g n rate b a s mic n u tor c n ertor (s e IEC 6 14 -2) re uire a

intern l a.c v lta e circ it to s p ly th re tifier sta k This intern l a.c v lta e e c e s th d.c v lta e for

p y ic l re s n This intern l a.c circ it is n t to b c n id re a a hig er v lta e circ it within th me nin of

this cla s Betwe n intern l circ its a d e tern l hig er v lta e circ its, prote tiv s p ratio is re uire

NOT 3 In d.c s stems with b terie , th b tery c argin a d flo tin v lta e e c e th b tery n min l

v lta e, d p n in o th ty e of b tery This d e n t re uire a y prote tiv pro isio s in a ditio to th s

s e ifie in this cla s Th c argin v lta e s o ld n t e c e a ma imum v lu of 7 V a.c or 15 V d.c a

a pro riate a c rdin to th e viro me tal situ tio a giv n in Ta le 1 of IEC612 1:19 2

414.3 So rc s for SELV a d PELV

The fol owin sources may b u ed for SELV an PELV s stems:

414.3.1 A safety isolatin tran former in ac ordan e with IEC 615 8-2-6

414.3.2 A source of c r ent providin a degre of safety eq ivalent to that of the safety

isolatin tran former sp cified in 414.3.1 (e.g motor generator with win in s providin

eq ivalent isolation)

414.3.3 An electroc emical source (e.g a b t ery) or another source in e en ent of a

hig er voltage circ it (e.g a diesel-driven generator)

414.3.4 Certain electronic devices complyin with a pro riate stan ard where provision

have b en taken in order to en ure that, even in the case of an internal fault, the voltage at

the outgoin terminals can ot ex e d the values sp cified in 414.1.1 Hig er voltages at the

outgoin terminals are, however, p rmited if it is en ured that, in case of contact with a l ve

p rt or in the event of a fault b twe n a lve p rt an an exp sed-con u tive-p rt, the voltage

at the output terminals is immediately red ced to those values or les

NOT 1 Ex mple of s c d vic s in lu e in ulatio te tin e uipme t a d mo itorin d vic s

NOT 2 Wh re hig er v lta e e ist at th o tg in termin ls, c mpla c with this cla s ma b a s me if

th v lta e at th o tg in termin ls is within th lmits s e ifie in 414.1.1 wh n me s re with a v ltmeter

h vin a intern l re ista c of at le st 3 0 0 Ω

414.3.5 Mo ie sources s p l ed at low voltage, e.g safety isolatin tran formers or motor

generators, s al b selected or erected in ac ordan e with the req irements for protection by

the u e of double or reinforced in ulation (se Clau e 412)

414.4 Re uireme ts for SELV a d PELV circ its

414.4.1 SELV an PELV circ its s al have

– b sic in ulation b twe n l ve p rts an other SELV or PELV circ its, an

– protective se aration from l ve p rts of circ its not b in SELV or PELV, provided by

double or reinforced in ulation or by b sic in ulation an protective s re nin for the

hig est voltage present

SELV circ its s al have b sic in ulation b twe n l ve p rts an e rth

The PELV circ its an /or exp sed-con u tive-p rts of eq ipment s p l ed by the PELV

circ its may b e rthed

NOT 1 In p rtic lar, prote tiv s p ratio is n c s ary b twe n th lv p rts of ele tric l e uipme t s c a

rela s, c nta tors, a xi ary switc e , a d a y p rt of a hig er v lta e circ it or aF LV circ it

NOT 2 Th e rthin of P LV circ its ma b a hie e b a c n e tio to e rth or to a e rth d prote tiv

c n u tor within th s urc its lf

414.4.2 Protective se aration of wirin s stems of SELV an PELV circ its from the l ve

p rts of other circ its, whic have at le st b sic in ulation, may b ac ieved by one of the

fol owin ar an ements:

– SELV an PELV circ it con u tors s al b en losed in a non-metal c s e th or in ulatin

en los re in ad ition to b sic in ulation;

– SELV an PELV circ it con u tors s al b se arated from con u tors of circ its at

voltages hig er than Ban I by an e rthed metal c s e th or e rthed metal c s re n;

– circ it con u tors at voltages hig er than Ban I may b contained in a multi-con u tor

ca le or other groupin of con u tors if the SELV an PELV con u tors are in ulated for

– the wirin s stems of other circ its are in complan e with 412.2.4.1;

– ph sical se aration

414.4.3 Plu s an soc et outlets in SELV an PELV s stems s al comply with the fol owin

req irements:

– plu s s al not b a le to enter soc et outlets of other voltage s stems;

– soc et outlets s al not admit plu s of other voltage s stems;

– plu s an soc et outlets in SELV s stems s al not have a protective con u tor contact

414.4.4 Exp sed-con u tive-p rts of SELV circ its s al not b con ected to e rth, or to

protective con u tors or exp sed-con u tive-p rts of another circ it

NOT If th e p s d-c n u tiv -p rts of S LV circ its are la le to c me into c nta t, eith r fortuito sly or

inte tio aly, with th e p s d-c n u tiv -p rts of oth r circ its, prote tio a ain t ele tric s o k n lo g r

d p n s s lely o prote tio b S LV, b t als o th prote tiv pro isio s to whic th later e p s

d-c n u tiv -p rts are s bje t

414.4.5 If the nominal voltage ex e d 2 V a.c or 6 V d.c or if the eq ipment is

immersed, b sic protection s al b provided for SELV an PELV circ its by:

– in ulation in ac ordan e with Clau e A.1, or

– b r iers or en los res in ac ordan e with Clau e A.2

Basic protection is generaly u neces ary in normal dry con ition for

– SELV circ its where the nominal voltage do s not ex e d 2 V a.c or 6 V d.c

– PELV circ its where the nominal voltage do s not ex e d 2 V a.c or 6 V d.c an

exp sed-con u tive-parts an /or the lve p rts are con ected by a protective con u tor to

the main e rthin terminal

In al other cases, b sic protection is not req ired if the nominal voltage of the SELV or PELV

s stem do s not ex e d 12 V a.c or 3 V d.c

415 Additional protection

NOT Ad itio al prote tio ma b s e ifie with th prote tiv me s re u d r c rtain c n itio s of e tern l

influ n e a d in c rtain s e ial lo atio s (s e th c re p n in Part 7of IEC 6 3 4)

415.1 Ad itional prote tion: re idual c r e t prote tive de ic s (RCDs)

415.1.1 The u e of RCDs with a rated resid al o eratin c r ent not ex e din 3 mA, is

recog ized in a.c s stems as ad itional protection in the event of fai ure of the provision for

b sic protection an /or the provision for fault protection or careles nes by u ers

NOT In Hu g ry R Ds with rate o eratin c re t n t e c e in 10 mA c n b u e a a ditio al prote tio

in in talatio s situ te o tsid

415.1.2 The u e of s c devices is not recog ized as a sole me n of protection an do s

not o viate the ne d to a ply one of the protective me s res sp cified in Clau e 41 to

Clau e 414

415.2 Ad itional prote tion: s p leme tary prote tiv e uipote tial bonding

NOT 1 Su pleme tary prote tiv e uip te tial b n in is c n id re a a a ditio to fa lt prote tio

NOT 2 Th u e of s p leme tary prote tiv b n in d e n t e clu e th n e to dis o n ct th s p ly for

oth r re s n , for e ample prote tio a ain t fire, th rmal stre s s in e uipme t, etc

NOT 3 Su pleme tary prote tiv b n in ma in olv th e tire in talatio , a p rt of th in talatio , a item of

IEC 6 3 4), or for oth r re s n

415.2.1 Sup lementary protective eq ip tential b n in s al in lu e al simultane u ly

ac es ible exp sed-con u tive-p rts of fixed eq ipment an extrane u -con u tive-p rts

in lu in where practica le the main metal c reinforcement of con tru tional reinforced

con rete The eq ip tential b n in s stem s al b con ected to the protective con u tors

of al eq ipment in lu in those of soc et outlets

ac es ible exp sed-con u tive-p rts an extrane u -cond ctive-p rts s al fulfis the

fol owin con ition:

a

V5

is the o eratin c r ent in A of the protective device

– for resid al c r ent protective devices (RCDs), I

∆n

– for overc r ent devices, the 5 s o eratin c r ent

Annex A

Provisions for basic protection

NOT Pro isio s for b sic prote tio pro id prote tio u d r n rmal c n itio s a d are a ple wh re s e ifie

a a p rt of th c o e prote tiv me s re

A.1 Ba ic insulation of l ve parts

NOT Th in ulatio is inte d d to pre e t c nta t with lv p rts

Live p rts s al b completely covered with in ulation whic can only b removed by

destru tion

For eq ipment, the in ulation s al comply with the relevant stan ard for the electrical

eq ipment

A.2 Bar iers or enclosures

NOT Bariers or e clo ure are inte d d to pre e t c nta t with lv p rts

A.2.1 Live p rts s al b in ide en los res or b hin b r iers providin at least the degre of

protection IPXXB or IP2X ex e t that, where larger o enin s oc ur d rin the re lacement of

p rts, s c as certain lampholders or fu es, or where larger o enin s are neces ary to al ow

the pro er fu ctionin of eq ipment ac ordin to the relevant requirements for the eq ipment:

– s ita le precaution s al b taken to prevent p rson or l vestoc from u intentional y

tou hin l ve p rts, an

– it s al b en ured, as far as practica le, that p rson wi b aware that l ve p rts can b

tou hed throu h the o enin an s ould not b tou hed intentional y, an

– the o enin s al b as smal as is con istent with the req irement for pro er fu ctionin

an for re lacement of a p rt

A.2.2 Horizontal to s rfaces of b r iers or en los res whic are re di y ac es ible s al

provide a degre of protection of at le st IPXXD or IP4X

A.2.3 Bar iers an en los res s al b firmly sec red in place an have s f icient sta i ty

an d ra i ty to maintain the req ired degre s of protection an a pro riate se aration from

l ve p rts in the k own con ition of normal service, takin ac ou t of relevant external

influen es

A.2.4 Where it is neces ary to remove b r iers or o en en los res or to remove p rts of

en los res, this s al b p s ible only

– by the u e of a key or to l, or

– afer dis on ection of the s p ly to l ve p rts again t whic the b r iers or en los res

aford protection, restoration of the s p ly b in p s ible only afer re lacement or

reclos re of the b r iers or en los res, or

– where an intermediate b r ier providin a degre of protection of at le st IPXXB or IP2X

prevents contact with l ve p rts, by the u e of a key or to l to remove the intermediate

b r ier

A.2.5 If, b hin a b r ier or in an en los re, items of eq ipment are in tal ed whic may

retain dan erou electrical c arges af er they have b en switc ed of (ca acitors, etc.), a

warnin la el is req ired Smal ca acitors s c as those u ed for arc extin tion, for delayin

the resp n e of relay , etc s al not b con idered dan erou

NOT Uninte tio al c nta t is n t c n id re d n ero s if th v lta e re ultin from static c arg s fal b low

12 V d.c in le s th n 5 s afer dis o n ctio from th p wer s p ly

Annex B

Obstacles and placing out of reach

B.1 Appl cation

The protective me s res of o stacles an placin out of re c provide b sic protection only

They are for a plcation in in talation with or without fault protection that are control ed or

s p rvised by s i ed or in tru ted p rson

The con ition of s p rvision u der whic the b sic protective provision of An ex B may b

a pl ed as p rt of the protective me s re are given in 410.3.5

B.2 Obstacles

NOT Ob ta le are inte d d to pre e t u inte tio al c nta t with lv p rts b t n t inte tio al c nta t b

d lb rate circ mv ntio of th o sta le

B.2.1 Obstacles s al prevent

– u intentional b di y a pro c to lve p rts, an

– u intentional contact with l ve p rts d rin the o eration of l ve eq ipment in normal

service

B2.2 Obstacles may b removed without u in a key or to l but s al b sec red so as to

prevent u intentional removal

B.3 Placing out of rea h

NOT Prote tio b pla in o t of re c is inte d d o ly to pre e t u inte tio al c nta t with lv p rts

B.3.1 Simultane u ly ac es ible p rts at dif erent p tentials s al not b within arm's re c

NOT Two p rts are d eme to b simulta e u ly a c s ible if th y are n t more th n 2,5 m a art (s e Fig re

B.1)

B.3.2 If a normal y oc upied p sition is restricted in the horizontal direction by an o stacle

(e g han rai , mes s re n) af ordin a degre of protection les than IPXXB or IP2X, arm's

re c s al exten from that o stacle In the overhe d direction, arm's re c is 2,5 m from

the s rface, S, not takin into ac ou t an intermediate o stacle providin a degre of

protection les than IPXXB

NOT Th v lu s of arm's re c a ply to c nta t dire tly with b re h n s with ut a sista c (e.g to ls or

la d r)

B.3.3 In places where bulk or lon con u tive o jects are normal y han led, the distan es

req ired by B.3.1 an B.3.2 s al b in re sed, takin ac ou t of the relevant dimen ion of

those o jects

R1,2

IE 42/01

Figure B.1 – Zone of arm's re c

Annex C

Protective measures for appl cation only when the instal ation is

control ed or under the supervision of ski led or instructed persons

NOT Th c n itio s of s p rvisio u d r whic th fa lt prote tiv pro isio s (prote tio a ain t in ire t

c nta t of An e C ma b a ple a p rt of th prote tiv me s re are giv n in 410.3.6

C.1 Non-conducting location

NOT 1 This prote tiv me s re is inte d d to pre e t simulta e u c nta t with p rts whic ma b at difere t

p te tial thro g faiureof th b sic in ulatio of lv p rts

NOT 2 In Swe e prote tio b me n of n n-c n u tin lo atio is n t p rmite

C.1.1 Al electrical eq ipment s al comply with one of the provision for b sic protection

des rib d in An ex A

C.1.2 Exp sed-con u tive-p rts s al b ar an ed so that u der ordinary circ mstan es

p rson wi not come into simultane u contact with

– two exp sed-con u tive-p rts, or

– an exp sed-con u tive-p rt an an extrane u -con u tive-p rt,

if these p rts are l a le to b at dif erent p tential throu h fai ure of the b sic in ulation of l ve

p rts

C.1.3 In a non-con u tin location there s al b no protective con u tor

C.1.4 Subclau e C.1.2 is fulfi ed if the location has an in ulatin flo r an wal s an one or

more of the fol owin ar an ements a pl es:

a) Relative sp cin of exp sed-con u tive-p rts an of extrane u -con u tive-p rts as wel

as sp cin of exp sed-con u tive-p rts

This sp cin is s f icient if the distan e b twe n two p rts is not les than 2,5 m; this

distan e may b red ced to 1,2 m outside the zone of arm's re c

b) Interp sition of ef ective o stacles b twe n exp sed-con u tive-p rts an extrane u

-con u tive-p rts

Su h o stacles are s f iciently ef ective if they exten the distan es to b s rmou ted to

the values stated in p int a) a ove They s al not b con ected to e rth or to exp sed

-con u tive-p rts; as far as p s ible they s al b of in ulatin material

c) In ulation or in ulatin ar an ements of extrane u -con u tive-p rts

The in ulation s al b of s f icient mec anical stren th an b a le to with tan a test

voltage of at le st 2 0 0 V L akage c r ent s al not ex e d 1 mA in normal con ition of

– 10 kΩ, where the nominal voltage of the in tal ation ex e d 5 0 V.

NOT If at a y p int th re ista c is le s th n th s e ifie v lu , th flo rs a d wals are d eme to b

e tra e u -c n u tiv -p rts for th p rp s s of prote tio a ain t s o k

C.1.6 The ar an ements made s al b p rmanent an it s al not b p s ible to make them

inef ective They s al also en ure protection where the u e of mo i e or p rta le eq ipment

is en isaged

NOT 1 Ate tio is drawn to th ris th t, wh re ele tric l in talatio s are n t u d r efe tiv s p rvisio ,

furth r c n u tiv p rts ma b intro u e at a later d te (e.g mo ie or p rta le Cla s I e uipme t or

e tra e u -c n u tiv -p rts s c a metal c water pip s), whic ma in ald te c mpla c with C.1.6

NOT 2 It is e s ntial to e s re th t th in ulatio of flo r a d wals c n ot b afe te b h midity

C.1.7 Precaution s al b taken to en ure that extrane u -con u tive-p rts can ot cau e a

p tential to a p ar external y to the location con erned

C.2 Prote tion by e rth- ree loc l e uipotential bonding

NOT Earth-re lo al e uip te tial b n in is inte d d to pre e t th a p ara c of a d n ero s to c v lta e

C.2.1 Al electrical eq ipment s al comply with one of the provision for b sic protection

(protection again t direct contact des rib d in An ex A

C.2.2 Eq ipotential b n in con u tors s al intercon ect al simultane u ly ac es ible

exp sed-con u tive-p rts an extrane u -con u tive-p rts

C.2.3 The local eq ip tential b n in s stem s al not b in electrical contact with e rth

directly, nor throu h exp sed-con u tive-p rts, nor throu h extrane u -con u tive-p rts

NOT Wh re this re uireme t c n ot b fulfi e , prote tio b a tomatic dis o n ctio of s p ly is a plc ble

(s e Cla s 41 )

C.2.4 Precaution s al b taken to en ure that p rson enterin the eq ip tential location

can ot b exp sed to a dan erou p tential dif eren e, in p rtic lar, where a con u tive flo r

in ulated from e rth is con ected to the e rth- re eq ip tential b n in s stem

C.3 Electric l s paration for the supply of more than one item of cur ent using

equipment

NOT Ele tric l s p ratio of a in ivid al circ it is inte d d to pre e t s o k c re ts thro g c nta t with

e p s d-c n u tiv -p rts th t ma b e ergiz d b a fa lt in th b sic in ulatio of th circ it

C.3.1 Al electrical eq ipment s al comply with one of the provision for b sic protection

des rib d in An ex A

C.3.2 Protection by electrical se aration for the s p ly of more than one item of a p ratu

s al b en ured by compl an e with al the req irements of Clau e 413 ex e t 413.1.2, an

with the fol owin req irements

C.3.3 Precaution s al b taken to protect the se arated circ it from damage an in ulation

fai ure

C.3.4 The exp sed-con u tive-p rts of the se arated circ it s al b con ected together by

in ulated, non-e rthed eq ip tential b n in con u tors Su h con u tors s al not b

con ected to the protective con u tors or exp sed-cond ctive-p rts of other circ its or to an

extrane u -con u tive-p rts

NOT Se Note to 413.3.6

C.3.5 Al soc et outlets s al b provided with protective contacts whic s al b con ected

to the eq ip tential b n in s stem provided in ac ordan e with C.3.4

C.3.6 Ex e t where s p lyin eq ipment with double or reinforced in ulation, al flexible

ca les s al emb d a protective con u tor for u e as an eq ip tential b n in con u tor in

ac ordan e with C.3.4

C.3.7 It s al b en ured that if two faults af ectin two exp sed-con u tive-p rts oc ur an

these are fed by con u tors of diferent p larity, a protective device s al dis on ect the

s p ly in a dis on ectin time conformin with Ta le 41.1

C.3.8 It is recommen ed that the prod ct of the nominal voltage of the circ it in volts an

len th, in metres, of the wirin s stem s ould not ex e d 10 0 0 V/m, an that the len th of

the wiring s stem s ould not ex e d 5 0 m

Annex D

Annex D

o