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4． IEC 60335-1中什么是电子开关？
. L/ y% `: U: \/ ONote: 9 `6 ~) O+ U; _: H- {
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。
, h8 Z: C- i! w& @; A4.2 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）
/ L' h8 X; @1 i/ X4.3 24.1.3和Annex H也得看看。! y* [% C( D: @3 y3 T0 T8 d4 i
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5． 关于IEC60335-1 cl 16关于泄漏电流加倍的讨论。3 N Q& P4 O" C
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.) y3 K n1 T% X9 }/ a
If the appliance is functionally switched off by a single-pole disconnection, then one end is left
h- b8 E9 D8 f2 q, X3 H4 C b: Jconnected to the supply since the appliance is only functionally off. The leakage current # d' {7 |0 Y0 A
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.
: J. w" O9 d- a8 CWhen 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. . J) n Q, q/ [. k* E- k6 W% N
4 h0 B' V* j; O# {
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).
! @9 e, k' r5 u9 B) ?2 K2 |: I+ L" o7 y' S& S! u, i1 ]
If the appliance is switched off by an all pole disconnection switch or by withdrawal of a plug
S8 u& Q7 _0 t8 P ]0 {. Z5 r, n5 Othen one end is not left connected to the supply when the appliance is off and the leakage
% C" T! M2 c+ q0 q% N( T3 Wcurrent in the off position will be zero. The leakage current value measured during the test of ' o* Y" l: B+ ^
16.2 will be twice the mean value experienced by the insulation in practice.
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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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