|
|
4． IEC 60335-1中什么是电子开关？
7 `/ N( f$ I) `' G( t- T& ANote:
9 l4 k& {8 C/ p+ O# t8 d4.1 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。
0 @" g( c2 [ J) @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）2 A. r5 k! }4 @: j4 |: ?% |& O
4.3 24.1.3和Annex H也得看看。
5 L, O) f8 n$ l2 ^; o+ |) f% t
a+ V9 M# Q1 k. }5． 关于IEC60335-1 cl 16关于泄漏电流加倍的讨论。9 x, ^ P l6 i
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.1 k" A# F0 r& z9 Q! W
If the appliance is functionally switched off by a single-pole disconnection, then one end is left
7 X, `8 F2 w5 G- Kconnected to the supply since the appliance is only functionally off. The leakage current 9 Y: j( }5 H; e
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.7 b: ]* u: ?8 F2 K
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. ' Q) O9 y V: H7 e
1 O6 p: D! }- \" Q* ]; m
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). , U% m5 a" H; J) n8 d
; |8 l+ L( x3 ]1 t4 O
If the appliance is switched off by an all pole disconnection switch or by withdrawal of a plug
) {* A! i/ [7 g' L, T- othen one end is not left connected to the supply when the appliance is off and the leakage ' s/ a& G0 V4 ]8 E7 f" n2 ]
current in the off position will be zero. The leakage current value measured during the test of 1 ]$ `+ j( D$ u" T/ w
16.2 will be twice the mean value experienced by the insulation in practice.
0 R6 ~2 c: T, D- P7 i7 a3 \( [( s! Y/ d$ ^+ v
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. |
|
|关于安规|小黑屋|安规QQ群|Archiver|手机版|安规网
( 粤ICP13023453-10 )
窥视卡
雷达卡
发表于 2009-4-11 01:26
显身卡