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4. IEC 60335-1中什么是电子开关?
8 v* {& G: D; O, r1 DNote:
6 r$ A8 x2 |$ k% a R4.1 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。
, i! O5 A; E% u8 P4.2 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)! O! P0 K+ t1 _& z- s8 z. H% ~
4.3 24.1.3和Annex H也得看看。
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5. 关于IEC60335-1 cl 16关于泄漏电流加倍的讨论。. B6 G0 U/ r3 s& w1 | O+ l. J
Note: 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.
2 `5 W0 j0 w v! w2 A, TIf the appliance is functionally switched off by a single-pole disconnection, then one end is left
) S. u5 s2 R( p. P7 N. f" e, gconnected to the supply since the appliance is only functionally off. The leakage current
1 a" i5 _# P! [- G9 `" rdistribution 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.
% J, P* ?& {( k3 XWhen 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. 7 A$ J( O% G# h8 e. {+ O f
! }2 l# N% C! a+ @5 u& w* CWhen 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).
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6 _# s6 }+ i( ~" ^! A1 z1 |, }' t; GIf the appliance is switched off by an all pole disconnection switch or by withdrawal of a plug 1 ~: e' H+ {! j$ }7 y4 D
then one end is not left connected to the supply when the appliance is off and the leakage . [1 b; X7 |# M7 P
current in the off position will be zero. The leakage current value measured during the test of 9 _4 S0 q' T4 V0 l, r: r, n$ U' ^
16.2 will be twice the mean value experienced by the insulation in practice. ; E6 ]7 @9 F4 h/ }' [7 }5 t
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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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