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60950的2.1.1.7写到:/ x* @/ w9 b! M+ q5 Q
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No test for shock hazard is required unless the nominal voltage of the MAINS SUPPLY exceeds 42,4 V peak or 60 V d.c.
9 [$ k+ |( x$ J- X' H' u就是输入超过SELV的就要去考虑电容放电,这是条件一;
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" i: R( ~' `8 i: r9 @Equipment is considered to comply if any capacitor having a marked or nominal capacitance exceeding 0,1 uF and in circuits connected to the MAINS SUPPLY has a means of discharge resulting in a time constant not exceeding: 1 s for PLUGGABLE EQUIPMENT TYPE A;
, ~ l# [; M% u; t& h# D4 ENOTE During an interval equal to one time constant, the voltage will have decayed to 37 % of its original value.# @: N7 o! s4 g! V' F, {, ?
条件二,如果输入电容(一般看前面跨接L/N的X电容)超过0.1uF的话,针对PLUGGABLE EQUIPMENT TYPE A(非工业插头)产品,它的放电时间常数不能超过1S;3 p D2 g4 g( m& z) ]1 \8 J$ [0 Z
这个放电时间常数计算比较复杂,一般情况都是通过测试去判定,1S内plug端的电压(240VrmsX1.4.1=340Vpeak)下降到初始电压的37%(125.8Vpeak)就pass了。 |
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