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4． IEC 60335-1中什么是电子开关？
' T$ z5 v/ |" Q& |Note: + E: Q6 I" F$ N# W0 _
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。5 U5 V7 I1 q# k
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） E% P# M S [& n
4.3 24.1.3和Annex H也得看看。
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( l: }# g. d0 B5． 关于IEC60335-1 cl 16关于泄漏电流加倍的讨论。
2 U; Z* C+ C1 y; z9 p% x! y9 p+ XNote: 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.
' t( C9 i& k! H8 `7 E" J- vIf the appliance is functionally switched off by a single-pole disconnection, then one end is left 1 f) Y" h- w9 L/ ?8 r4 l4 z
connected to the supply since the appliance is only functionally off. The leakage current 3 Z: b$ V$ r2 W- M6 L! I/ h
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.% S# y; r4 j! i8 ]' Q& F
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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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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If the appliance is switched off by an all pole disconnection switch or by withdrawal of a plug
4 C% k& _% j3 z ]! Tthen one end is not left connected to the supply when the appliance is off and the leakage : a% W( f; b" K$ I
current in the off position will be zero. The leakage current value measured during the test of + w# Z0 _% T) E6 c& b! u& ]1 E
16.2 will be twice the mean value experienced by the insulation in practice. 6 v: f- X$ _6 m) T" S3 L
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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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发表于 2009-4-11 01:26
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