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1.2.23* ]: J2 H* U }, M, q8 a
class II luminaire
4 B; J6 T$ ~8 q) `, P# Jluminaire in which protection against electric shock does not rely on basic insulation only, but in
G* Z7 a5 a% D4 Iwhich additional safety precautions such as double insulation or reinforced insulation are) V- Z, R- |$ o- @3 D# y& k
provided, there being no provision for protective earthing or reliance upon installation
2 T/ U* R E) Z1 t* g# tconditions.
, o4 H. H( G. o% w8 O, W* fNOTE 1 Such a luminaire may be of one of the following types:
" V: K& P6 G7 O, a5 @/ ?; g+ j& ua) A luminaire having a durable and substantially continuous enclosure of insulating material which envelopes all
& F& |2 l5 X# G6 S$ R4 |metal parts with the exception of small parts such as nameplates, screws and rivets which are isolated from live0 E1 s F3 X: {
parts by insulation at least equivalent to reinforced insulation. Such a luminaire is called an insulation encased# e! P8 V2 `' K) e& T
class II luminaire.1 @; x9 c3 J8 S7 G; |
b) A luminaire having a substantially continuous enclosure of metal, in which double insulation is used throughout,/ u) E* \/ I+ x( y% E/ V' A4 Y
except for those parts where reinforced insulation is used because the application of double insulation is
0 s' n+ z9 V/ d9 j2 dmanifestly impracticable. Such a luminaire is called a metal-encased class II luminaire.) k5 C5 z! f/ \
c) A luminaire which is a combination of types a) and b) above.6 G# I1 r0 i/ m) R* N! I9 k/ V% @ v& E
NOTE 2 The enclosure of an insulation-encased class II luminaire may form a part or the whole of the
1 F5 @! C0 O& V& `supplementary insulation or the reinforced insulation.
4 D* j( S+ e: A1 kNOTE 3 If earthing is provided to assist starting, but is not connected to an accessible metal part, the luminaire
- r7 w0 n% L. b% C8 b( ~) xmay still be deemed to be of class II. Accessible metal parts in compliance with the appropriate IEC lamp
C: C! T: b; y7 b( especification and other metal parts not normally earthed and not normally accessible during normal use are not
: S' |+ g6 w( a6 S3 H& v+ r N& Uregarded to be conductive parts which may cause an electric shock unless the tests of Annex A show them to be6 C. U* S m% ?, y
live parts.) r' L! E; H# `! u5 W
NOTE 4 If a luminaire with double insulation and/or reinforced insulation throughout has an earthing terminal or an/ a% M; o+ J$ T
earthing contact, it is class I construction. However, a fixed class II luminaire intended for looping-in may have an
9 g" U! M$ j% B9 }1 a' J+ V( D4 O0 Jinternal terminal for maintaining the electrical continuity of an earthing conductor not terminating in the luminaire,
$ r, ]* I# T. \$ Z9 jprovided that the terminal is insulated from accessible metal parts by class II insulation.
# V. V9 d1 |/ c* UNOTE 5 Class II luminaires may have parts in which protection against electric shock relies on operation at safety% @8 E# ~, J6 T2 D ?2 w& p7 t3 A
extra-low voltage (SELV).
$ _9 c+ C4 x9 `- P1.2.24( C8 g; ^9 V$ c4 p' f( |+ C7 X
class III luminaire( s/ i, ?, D! K- U6 N& a5 J: h0 k
luminaire in which protection against electric shock relies on supply at safety extra-low voltage6 _4 D/ r% G6 w8 d' Y5 W+ P! q
(SELV) and in which voltages higher than those of SELV are not generated.
5 }* U, D) d% ~6 k/ i% HNOTE A class III luminaire should not be provided with means for protective earthing. |
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