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4. IEC 60335-1中什么是电子开关?
/ J1 t( C- r S5 S, P I- p8 y/ K3 J/ GNote:
- N) Y' p' C, n$ J4.1 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。+ Z* M- i; L1 i0 N! e+ g
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)
4 b5 W7 R; e; `* l8 f5 W4.3 24.1.3和Annex H也得看看。1 ~ T5 f- H/ A( P" I9 i- G# e- r
% }5 ~1 B& L; E2 G _% ?) K P7 `5. 关于IEC60335-1 cl 16关于泄漏电流加倍的讨论。
4 |, }7 ]- f' d! H7 sNote: 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.* g' X" V- j" { f9 o" R/ i
If the appliance is functionally switched off by a single-pole disconnection, then one end is left
- \( h3 s1 A$ r, c3 O9 T, b/ {3 sconnected to the supply since the appliance is only functionally off. The leakage current 1 b+ f/ W- i1 x/ U2 s, Z8 O/ S1 n/ c
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.( q: ]3 X' Z/ x V7 |7 u
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. & O0 Y" y% I9 u' M$ F
, G8 q4 t0 q% y4 d1 i+ H* e8 cWhen 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).
) N4 i5 [& x6 T) n) F; Q; z6 p! k7 N9 F+ _9 x
If the appliance is switched off by an all pole disconnection switch or by withdrawal of a plug
2 v" O% W& p* E' nthen one end is not left connected to the supply when the appliance is off and the leakage
6 T6 v; {' Y6 d& J* bcurrent in the off position will be zero. The leakage current value measured during the test of
% \5 n1 m. e J C% U16.2 will be twice the mean value experienced by the insulation in practice. 0 B& Y+ ~6 Y! ?# u# B5 ]: p4 Y
* w2 B1 d/ z/ g0 U6 nIt 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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