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(接着上贴说)7 t5 \, }0 } s6 i5 f5 ^
在IEC 60065里: b) the touch current, expressed as the correspinding voltages U1 and U2, and measured in accordance with IEC 60990, with the measuring network described in annex D of this standard, shall not exceeds the following values:% s3 r a8 h2 x
- for a.c.: U1=35V (peak) and U2=0,35V (peak);
3 p% z5 y5 q. q$ U2 F$ o2 p- for d.c.: U1: 1,0V
9 F# J% J" X( y2 q# R- B在IEC 60065中,请注意电压的测量是在以下条件下测的:In order to verify that a part or a contact of a terminal is hazardous live, the following measurements are carried out between any two parts or contacts, then between any part or contqact and either pole of the supply source usded during the test. 换句话说,是既要测输出端子间的电压,也要测输入端与次级输出的电压,如果器具接230V市电,则条件一)肯定不会满足了,从而要求测接触电流等。
& G' j8 Q) M- T0 ^9 c7 h我想问的是,为什么要测试输入与输出的电压呢?$ m/ ^- p0 Y4 w. ?4 U* L8 [
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在IEC 61558-1里,测试电压的方法也与 IEC 60065相同:cl 9.1.1.1 compliance is checked by measurements carried out between any two conductive parts.也要测输入与输出间的电压的。$ e6 H* i, l8 D4 i, i$ h0 u4 l
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在IEC 60950-1里是这样定义hazardous voltage的:6 ^, A, a0 _7 W3 p% ^* }. P
cl 1.2.8.6 HAZARDOUS VOLTAGE : voltage exceeding 42,4V peak, or 60V d.c., existing in a circuit that does not meet the requirements for either a limited current circuit or a TNV circuit.. C8 x) ]& d) ^$ ?9 \
这个定义是不是想说明,即使电压超过42,4V peak, or 60V d.c,但只要是满足限流电路 (注:限流电路与家电中的保护性阻抗电路是一致的)5 ?8 ~! Y5 x5 L
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从这几个标准中,大家觉得是要同时满足条件一)和条件二)呢?还是其中之一即可。
- n4 \1 `$ h; y换句话说,即使手可摸到的电压超过安全特低电压(SELV),但只要满足保护阻抗电路条件/限流电路条件等,就可以认为是安全的,从而可以手触摸。 |
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