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4. IEC 60335-1中什么是电子开关?
7 L' b' s- {# f+ |/ `6 BNote: ' d) Q; {' _4 P! p, c
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。* N" d. p" C E% S& T
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)
& x+ {! w% V' G* G8 N# A8 k4.3 24.1.3和Annex H也得看看。
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0 m# |* ^! n: S' x' E3 }! u5. 关于IEC60335-1 cl 16关于泄漏电流加倍的讨论。$ A8 g7 n' \1 K0 D/ s7 W/ \8 `
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.
7 g! B! S0 W" j6 `$ `- iIf the appliance is functionally switched off by a single-pole disconnection, then one end is left
1 |4 C+ E! `/ w p# Kconnected to the supply since the appliance is only functionally off. The leakage current
6 Q6 l) Y2 }. @% @- o- S1 Q& B bdistribution 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.$ V1 E. J. a. z! J. c4 m7 a
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.
* }" @$ l8 I) Q" x) C
9 }* j8 o0 }' ?7 r1 M$ {; t2 yWhen 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 ( c# Z( V; c! X+ d9 ^6 S
then one end is not left connected to the supply when the appliance is off and the leakage 7 d8 G y$ D' {/ l
current in the off position will be zero. The leakage current value measured during the test of
# ~- J+ }" h1 f: T6 u* K16.2 will be twice the mean value experienced by the insulation in practice.
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- b; v6 Y8 _ ], Q; S: gIt 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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