|
60950的2.1.1.7写到:: N; a! R( M+ j/ P. ^$ r
# X: h1 s9 a& D
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.; O9 {1 i: L' q( ] }5 |
就是输入超过SELV的就要去考虑电容放电,这是条件一;. ^, {4 k8 Q+ p% ?7 Y0 S
: K6 W& Y0 R: k2 _& @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;$ o) I( W6 K, A ^: v' G- a
NOTE During an interval equal to one time constant, the voltage will have decayed to 37 % of its original value.
3 ^+ o7 Z# b; G+ e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;: h+ m( V* T% v- ^; }6 p
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。 |
|