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4. IEC 60335-1中什么是电子开关?
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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。
, J/ Z W' F- E' J* r4.2 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)
5 ~/ L9 S( v8 I K9 F4.3 24.1.3和Annex H也得看看。
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2 A4 T Z Z7 c- N6 d R5. 关于IEC60335-1 cl 16关于泄漏电流加倍的讨论。0 V% X& C; U5 u s
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.
. y" h7 O% s$ }6 \, q W9 z% hIf the appliance is functionally switched off by a single-pole disconnection, then one end is left 8 G/ f' t# H. J8 t- C( ~
connected to the supply since the appliance is only functionally off. The leakage current 9 r+ U \1 x3 M- n" }
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.% u" e1 A: j0 g0 n0 ]
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. % o% t& D! o2 I' a
V! R+ G. ~3 j) B: Y0 l2 u* G0 R* ~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). 6 T8 E; q9 t! c' M+ C$ Y- u
( ~4 e1 Z: Z" \1 U2 jIf the appliance is switched off by an all pole disconnection switch or by withdrawal of a plug
$ i) |5 G% s3 p. }. M) a8 _) dthen one end is not left connected to the supply when the appliance is off and the leakage # d P6 I+ |' J, I. X% L R
current in the off position will be zero. The leakage current value measured during the test of * L5 {' J' w M2 `1 W: ~
16.2 will be twice the mean value experienced by the insulation in practice. W8 L! r3 w! P+ i2 E
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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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