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4. IEC 60335-1中什么是电子开关?
) H2 w& k8 o3 G; e' x# ]% N LNote:
8 t3 n1 J; a# w) G4.1 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。
2 Q. w8 ?* ?9 }6 j4.2 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)/ X) }: e9 D& X9 B+ o& V' R
4.3 24.1.3和Annex H也得看看。2 z5 C: q# x9 w! ?
" \: x* |) S& r+ g J) g5. 关于IEC60335-1 cl 16关于泄漏电流加倍的讨论。# d' x2 S1 ~" G% x/ ]
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.4 l2 v9 ^3 h* q
If the appliance is functionally switched off by a single-pole disconnection, then one end is left 2 M) [* m$ e& P* u
connected to the supply since the appliance is only functionally off. The leakage current * p" [8 J% k8 c$ A: y" ~
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.& E: o- V2 d1 _( Q) d$ l
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* g2 V; i$ p7 u
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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). 1 L, Z! V% B0 d5 l
- Q$ f. z8 n. i% C+ ^- PIf the appliance is switched off by an all pole disconnection switch or by withdrawal of a plug Z: r. G0 ~- \& c
then one end is not left connected to the supply when the appliance is off and the leakage
$ ?2 W* D9 ?# A& F5 | ^0 v( hcurrent in the off position will be zero. The leakage current value measured during the test of
" Q% t9 ^; N, w+ X0 X, k16.2 will be twice the mean value experienced by the insulation in practice.
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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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