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请问论坛里面有没有对Class 2+ 功能接地结构比较熟悉的,讨论一下9 R+ X1 `, r, J, w+ L1 g
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像这种2类设备带功能接地的,一般认证机构划分到Class I 还是Class II呢?9 C8 b/ q: Q$ z" m+ A6 o
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是依据什么?, S5 G/ }6 J. v8 n, ~' B, w2 P
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如果划分到Class 2, 是不是需要标“回”符号呢?
. E2 S" e) ^2 T: O" KUL 60950 2.6.2 有对这个功能接地详细描述:! P( H: a0 R) c/ p$ q) ~# k
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1 K; b( V+ r; R! A2.6.2 Functional earthing0 T( j! l( L7 L; \) V5 O1 u7 A
If FUNCTIONAL EARTHING of accessible or inaccessible conductive parts is necessary, all of the" U' o3 g, S3 a0 R/ j
following apply to the FUNCTIONAL EARTHING circuit:
' A0 z; R' Y2 w; d7 k, I$ ^– the FUNCTIONAL EARTHING circuit shall be separated from parts at HAZARDOUS VOLTAGES in# A6 k8 O3 n+ u
the equipment by either:2 c% H: {1 p# i+ o% n' D2 K
• DOUBLE INSULATION or REINFORCED INSULATION; or$ J& p W1 `0 T3 c) j/ G' T
• a protectively earthed screen or another protectively earthed conductive
9 Y7 J8 b# X- |) Q' O; j+ Y+ Lpart, separated from parts at HAZARDOUS VOLTAGES by at least BASIC INSULATION;
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: g3 d$ u# l, f2 b" @– it is permitted to connect the FUNCTIONAL EARTHING circuit to a protective earth terminal
' K) c3 {# ~; ?6 c; m# \+ M) {or to a PROTECTIVE BONDING CONDUCTOR; and
/ k# \! X, ^3 n3 m– wiring terminals to be used only for FUNCTIONAL EARTHING shall not be marked by the" a2 W. ^0 F9 W" G' ~6 o- C
symbol (60417-IEC-5017) or by the symbol (60417-IEC-5019), except that,( S* P( e' i; i! {3 d) S% o' B
where a wiring terminal is provided on a component (for example, a terminal block) or
$ u+ w' ^ z9 T3 V5 t+ ~. U% k4 e" Bsubassembly, the symbol is permitted; and
- k* {7 E2 T2 M8 w* V5 vNOTE Other markings such as one of the symbols, (IEC 60417-5018 (DB:2002-10)) or (IEC 60417-5020
3 j5 w6 ~5 P) R. G+ u(DB:2002-10)), if appropriate, are permitted.+ I9 _, N8 S M M
– for internal FUNCTIONAL EARTHING conductors, the colour combination green-and-yellow+ u( L8 n. w0 [) W
shall not be used except in multipurpose preassembled components (for example,7 @1 c+ S- ]& y4 o
multi-conductor cables or EMC filters); and0 ~( ^3 e/ x3 l$ |+ c. [$ }( ^0 B
– in a power supply cord where a conductor having green-and-yellow insulation is
# B5 M3 v- ~' K# z! o* ?, Tused only to provide a FUNCTIONAL EARTHING connection:
j& P- z# S7 Y% ~• the equipment shall not be marked with the symbol (IEC 60417-5172+ \) U; ?- @0 M
(DB:2003-02)); and c, Z' }( V8 Q, {! I+ W4 D
• there are no requirements other than those in 3.1.9 regarding the! O, b- M6 d0 v/ L2 `9 M( O
termination of this conductor at the equipment end.# G" x. c1 p5 s
MARCH 27, 2007 CAN/CSA-C22.2 NO. 60950-1-07 ♦ UL 60950-1 89 |
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