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4. IEC 60335-1中什么是电子开关?' J$ P9 n9 Y a
Note: ; a# B0 A" ]) i0 t, Z
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。! Z4 K! p' i2 {5 n3 T, g0 q
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)
& x7 {: c4 x3 a4.3 24.1.3和Annex H也得看看。* C- P3 {9 o6 h# C5 X4 W" l
2 F6 D; t: ~2 i# P% R5. 关于IEC60335-1 cl 16关于泄漏电流加倍的讨论。
+ ?1 | k* N1 i; E+ V) H0 `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 d$ l% U8 ~, fIf the appliance is functionally switched off by a single-pole disconnection, then one end is left
. t9 Y6 a0 Q: d R6 ^. @connected to the supply since the appliance is only functionally off. The leakage current
' q" R( C z8 x0 O" A 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.$ ]$ I3 d3 m d$ z* L6 v% P
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. ( _4 {8 i. T9 _. c( M
% }$ [# l2 Q& Y1 J
When 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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- S1 e. z0 Y( l/ J0 z4 `) r$ Z4 uIf the appliance is switched off by an all pole disconnection switch or by withdrawal of a plug
' J2 o5 K6 B4 S. gthen one end is not left connected to the supply when the appliance is off and the leakage , S$ h: B- ^1 ^' k" h& r
current in the off position will be zero. The leakage current value measured during the test of ; H; N: E; s. [3 C, [
16.2 will be twice the mean value experienced by the insulation in practice.
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8 [# m9 m% F, J/ c& IIt 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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