标题: 保护阻抗的疑问 [打印本页] 作者: neilyan 时间: 2011-3-11 14:21 标题: 保护阻抗的疑问 EN61010 3.5.7中对保护阻抗定义：" Z& S9 r L; U3 A. r0 ?( I2 V
component, assembly of components or the combination of BASIC INSULATION and a current or! `3 z$ ^) M# Q
voltage-limiting device, whose impedance, construction and reliability are such that, when0 Y1 N6 C* l8 z) V9 J1 k$ N
connected between ACCESSIBLE conductive parts and parts which are HAZARDOUS LIVE, it 4 _( z) o& \$ [( U( ^4 A: h+ pprovides protection to the extent required by this standard in NORMAL CONDITION and SINGLE; c9 W9 O5 n+ \1 x; s4 @" y! A
FAULT CONDITION ; n1 [& b* E l( c: \7 |( g! x# b) } \
保护阻抗具体是指哪些呢？如果仅仅是防止可接触导电部件危险带电，那如果次级SELV电路不可接触，Y电容还算不算保护阻抗？I类产品的金属外壳和危险带电部件之间算the combination of BASIC INSULATION and a current or voltage-limiting device吗？作者: June.Zhao 时间: 2011-3-11 14:30
让我说，满足LCC的元器件一定是保护阻抗。例子：初次间双Y2电容串接作者: yuqijun 时间: 2011-3-11 15:45
假如就一个Y1电容应该不算保护阻抗吧，作者: neilyan 时间: 2011-3-11 17:24
引用第2楼yuqijun于2011-03-11 15:45发表的 : " ~/ f! B; R. B% a; T- a ?$ R假如就一个Y1电容应该不算保护阻抗吧，
' Y! n$ s; C5 y5 @- u从定义上看，单独一个Y1电容也可以算保护阻抗，关键看后面的次级电路是不是可接触作者: June.Zhao 时间: 2011-3-14 08:46
一个不行吧。。8 n: g4 G# T' n/ |3 _6 ]* D1 E
22.42 Protective impedance shall consist of at least two separate components whose impedance is unlikely to change significantly during the lifetime of the appliance. If any one of the components is short-circuited or open-circuited the values specified in 8.1.4 shall not be exceeded. ! r& K+ w; R: U7 ^ i4 eNOTE: Resistors complying with test a) of subclause 14.1 of IEC 60065 and class Y capacitors complying with # |4 ^7 L# [) x! ?IEC 60384-14 are considered to be components having a sufficiently stable impedance