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4. IEC 60335-1中什么是电子开关?
# }4 x! u' i) ~+ u) L& {0 c" r: aNote:
0 m$ @; _! Q: Q& u, Y) t4 x4.1 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。
3 ?8 Z5 Q. c' ]9 n/ Q* x4.2 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)
6 ], n7 g( F5 n) H4 h! O; q4.3 24.1.3和Annex H也得看看。
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# ?) Y3 d/ c2 c. F; h8 a7 X5. 关于IEC60335-1 cl 16关于泄漏电流加倍的讨论。+ |; X9 l Y2 A. C$ Z; M
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.! h1 L6 w" r/ n% b4 z8 ?* |- Z
If the appliance is functionally switched off by a single-pole disconnection, then one end is left
* t3 w4 r; l- Z0 Z, F: W, Pconnected to the supply since the appliance is only functionally off. The leakage current * l8 M! k$ e: f
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.- d! q% ^! ]$ W) R6 n
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. 6 `2 ]+ k# Q) A+ c" F, _
7 t' C; z: O# {6 y" T1 j. P3 \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). # Q8 j: X" X) r! L4 i5 V
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If the appliance is switched off by an all pole disconnection switch or by withdrawal of a plug
: A% ~/ O+ T; Y1 z3 G$ j% Cthen one end is not left connected to the supply when the appliance is off and the leakage
. q7 X6 G# \: acurrent in the off position will be zero. The leakage current value measured during the test of ]8 g4 F& H3 ~7 G9 ~* p+ x1 m
16.2 will be twice the mean value experienced by the insulation in practice. + |4 ?0 q8 M: g: d0 \
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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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