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1.2.23' ~4 B9 X/ ?6 O1 ?9 B# o
class II luminaire4 X6 e# H# e# {' N0 c
luminaire in which protection against electric shock does not rely on basic insulation only, but in
" C, |/ j# n) y/ iwhich additional safety precautions such as double insulation or reinforced insulation are
# A6 T0 ]- q/ S( q& k2 E0 Q8 h6 Jprovided, there being no provision for protective earthing or reliance upon installation
. \% q- o' t7 w6 E$ x( Z( l& |conditions.
0 R1 g4 I: h' A3 [3 W$ ~( W5 |2 iNOTE 1 Such a luminaire may be of one of the following types:+ C* x7 \+ t$ q
a) A luminaire having a durable and substantially continuous enclosure of insulating material which envelopes all
R s! {4 t( ?& d9 g1 }metal parts with the exception of small parts such as nameplates, screws and rivets which are isolated from live( n) Q8 U1 |! `- V2 S2 o
parts by insulation at least equivalent to reinforced insulation. Such a luminaire is called an insulation encased$ _1 b1 v# c* G
class II luminaire.
+ Z* K5 K. O6 `& J, e+ I4 H Zb) A luminaire having a substantially continuous enclosure of metal, in which double insulation is used throughout,5 D* ?6 d* Y4 d0 L3 w
except for those parts where reinforced insulation is used because the application of double insulation is' N7 d# X' ~# i2 C9 m* d
manifestly impracticable. Such a luminaire is called a metal-encased class II luminaire.1 z$ `: v" H# }8 R2 w9 a1 p
c) A luminaire which is a combination of types a) and b) above./ |8 T2 [" `. D. B/ C( R% g6 i& a
NOTE 2 The enclosure of an insulation-encased class II luminaire may form a part or the whole of the( P" A* J$ S; f0 S, c8 u9 b
supplementary insulation or the reinforced insulation.
& ?5 n% H Q% s- I( z aNOTE 3 If earthing is provided to assist starting, but is not connected to an accessible metal part, the luminaire
6 ]6 d6 y6 J/ o/ O, u" [1 kmay still be deemed to be of class II. Accessible metal parts in compliance with the appropriate IEC lamp
( ^: Z2 l2 h' ]6 sspecification and other metal parts not normally earthed and not normally accessible during normal use are not- f" W% S+ F, F, z. R+ Q4 A
regarded to be conductive parts which may cause an electric shock unless the tests of Annex A show them to be
" i2 t l/ m) v) [live parts.
& i+ D; c: j5 C& vNOTE 4 If a luminaire with double insulation and/or reinforced insulation throughout has an earthing terminal or an
" z1 L8 [. T) oearthing contact, it is class I construction. However, a fixed class II luminaire intended for looping-in may have an7 B% o. S3 m: O0 P6 z
internal terminal for maintaining the electrical continuity of an earthing conductor not terminating in the luminaire,. m8 h& U4 }. V) P
provided that the terminal is insulated from accessible metal parts by class II insulation.2 j @* q+ Q( a1 W4 h
NOTE 5 Class II luminaires may have parts in which protection against electric shock relies on operation at safety* v+ w! z. S; E0 c, j+ m
extra-low voltage (SELV). |
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