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4. IEC 60335-1中什么是电子开关?) @* Y1 I( I& u4 n' X" ~
Note: * o% R: j \: ?) H3 O r# [$ x
4.1 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。
+ [" J) @3 G3 M1 i+ g# C% W& \4.2 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)
. d$ V6 u3 M i- `1 C5 D4.3 24.1.3和Annex H也得看看。( Z4 f1 E* h1 e' U+ u0 J
' D/ p- w! h6 M" T$ R! v. D" D5. 关于IEC60335-1 cl 16关于泄漏电流加倍的讨论。
8 p7 _7 y6 W E* rNote: 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.% ]! K7 `4 t' R! g7 n
If the appliance is functionally switched off by a single-pole disconnection, then one end is left 3 q1 X8 d* p1 ]
connected to the supply since the appliance is only functionally off. The leakage current
9 N7 H! G6 W2 h+ |- f4 Ldistribution 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.: B. P! w; i, X3 s* [
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.
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& v. A+ R A% X% h& s1 J' C9 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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If the appliance is switched off by an all pole disconnection switch or by withdrawal of a plug
- N6 Q; w! c* c+ _8 D4 [7 Fthen one end is not left connected to the supply when the appliance is off and the leakage
6 t/ u& L w3 s8 P; B* |. R( mcurrent in the off position will be zero. The leakage current value measured during the test of
+ I6 f1 }& j' d3 d3 B' w% q0 c16.2 will be twice the mean value experienced by the insulation in practice. / a4 X% l. L, R% U' ^
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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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