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4. IEC 60335-1中什么是电子开关?0 t. N5 [5 B5 Z
Note: " k7 [0 G0 P/ k& O
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。8 [( Z3 m- z) d5 y4 D8 @) O: 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)
' M/ q, h! ~( ^6 O0 ?* s7 @4.3 24.1.3和Annex H也得看看。* Q3 n0 ?. r, z! E# I% `
6 Q) f, \1 y& f0 _2 |; q- t5. 关于IEC60335-1 cl 16关于泄漏电流加倍的讨论。
5 Y Z1 K( N: n! |! wNote: 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.
; M$ V2 |: I" I5 Z1 m7 K$ vIf the appliance is functionally switched off by a single-pole disconnection, then one end is left
9 c: P/ j% S& B5 g3 _: g2 Xconnected to the supply since the appliance is only functionally off. The leakage current $ C, y; R( E! |! ?0 P
distribution 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." l% ~3 z* Y( H8 V9 l0 A1 f7 i
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. ! T% r, ~0 p! R
1 V) ^1 W5 ?" kWhen 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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' k9 U" z9 C8 Y8 [If the appliance is switched off by an all pole disconnection switch or by withdrawal of a plug 5 S8 h* }) d% T) g$ @# p
then one end is not left connected to the supply when the appliance is off and the leakage
5 r- V" ]7 J: o# m4 Ecurrent in the off position will be zero. The leakage current value measured during the test of 6 ?# k1 H% }6 b7 T$ x+ h
16.2 will be twice the mean value experienced by the insulation in practice. % C" W2 p& U- \$ Q* {! v
: d g" }$ V$ b uIt 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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