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4． IEC 60335-1中什么是电子开关？
' ?# \( G: [$ U9 F4 H& n0 G9 q' D, kNote:
$ c) }' [/ Z/ ]$ g* g; O4 a, f: x4.1 60335-1中提到电子开关涉及的测试最主要就是19.11.4, 当然这个要和off position (3.8.2)一起考虑才有意义。
% X" ?: P4 h# Z% Q7 P( N/ J9 J( r4.2 单纯地看待电子开关的话，请参看61058-1 table 15会很清楚：SSD without electrical contacts, SSD with serial contacts, SSD with parrel contacts, SSD with serial and parrllel contacts, 电子开关可以是半导体元件通断电实现off position, 或者是控制机械触点实现（例如继电器）
+ c; p. [( W" ?+ C4.3 24.1.3和Annex H也得看看。
C3 d' a1 ~9 u
4 D' K/ w8 A: O+ P5． 关于IEC60335-1 cl 16关于泄漏电流加倍的讨论。
3 Y9 b7 ?2 r) v' nNote: 这个问题在IEC TC 61 Chairman D.R.Johns写的IEC 60335 interpretation 里面有比较清晰的解释.
, i q4 ^1 k( @1 x2 s6 IIf the appliance is functionally switched off by a single-pole disconnection, then one end is left ! v1 X+ ~: M5 H7 R) n/ k6 m. [- b
connected to the supply since the appliance is only functionally off. The leakage current
: ~0 F1 n$ }7 ydistribution in the functionally off position can be as shown in figure A (格式问题，图贴不上来） and the nett leakage current will be Ix, where Ix is the leakage current per unit length of the insulation./ [+ } A. n, t0 x! t: }
When the appliance is tested according to the method detailed in 16.2, the leakage current distribution will be as shown in figure A (格式问题，图贴不上来）and the nett leakage current will be Ix. - G* p. P& A1 m
( m' n5 g0 L, x I4 w+ `9 ]. QWhen the appliance is on the leakage current distribution will be as shown in figure B (格式问题，图贴不上来）and the nett leakage current will be Ix/2 (since the appliance neutral is normally at or near earth potential).
/ R' `( b+ y" a3 @: g1 \/ {# f- N y/ B
! s7 V; y# q# C5 |% c8 fIf the appliance is switched off by an all pole disconnection switch or by withdrawal of a plug 3 T1 P: G$ \7 A. E0 K' a
then one end is not left connected to the supply when the appliance is off and the leakage
: R, x# @) W' n6 }1 i' s, @, ~/ x6 Dcurrent in the off position will be zero. The leakage current value measured during the test of
# n6 G5 k0 _- H) v16.2 will be twice the mean value experienced by the insulation in practice.
) L" B2 p% K4 R4 G6 {* a# \2 O5 T( p& S5 e% P: ?/ M ?& }
It is therefore, permissible to double the limit and still achieve the same level of safety as in the case where the appliance is switched off by a single pole disconnection switch. |
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发表于 2009-4-11 01:26
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