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标题: 335标准的14章瞬间过电压 [打印本页]

作者: amote2008    时间: 2008-1-16 15:42
标题: 335标准的14章瞬间过电压
什么情况下,可以不做此实验啊 ?+ W3 S7 j8 f9 L% L- Y1 y& R3 Y) v8 {
还有29章的过电压类别怎么判断啊 ?
作者: H-RH    时间: 2008-1-16 16:45
Annex K 定義了overvoltage categories 而這 categories 是由 IEC 60664-1 抽出來,/ Y" q3 o4 e( `, n& i& \6 r
似乎一般家電應是 category II
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IEC 60664-14 R1 [) E: ~4 C+ h
4.3.3.2.2 Equipment energized directly from the supply mains
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4 K  v6 D  a' _* B; @Technical committees shall specify the overvoltage category as based on the following general explanation of overvoltage categories (see also Clause 443 of IEC 60364-4-44):
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– Equipment of overvoltage category IV is for use at the origin of the installation.
, j% ?% P9 T9 BNOTE 1 Examples of such equipment are electricity meters and primary overcurrent protection equipment.3 R) m  Z( A9 [
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– Equipment of overvoltage category III is equipment in fixed installations and for cases where the reliability and the availability of the equipment is subject to special requirements.) l2 O  T: A" `
NOTE 2 Examples of such equipment are switches in the fixed installation and equipment for industrial use with permanent connection to the fixed installation.  C( O  J& _9 c: h

$ R$ B' ^5 [3 ]% V9 T– Equipment of overvoltage category II is energy-consuming equipment to be supplied from the fixed installation.# |1 \; o  j  k" ]
NOTE 3 Examples of such equipment are appliances, portable tools and other household and similar loads. If such equipment is subjected to special requirements with regard to reliability and availability, overvoltage category III applies.# v( e- I! t' L( E! z8 O, _( l

+ [* a# D6 I9 C5 c( i/ T– Equipment of overvoltage category I is equipment for connection to circuits in which measures are taken to limit transient overvoltages to an appropriately low level. These measures shall ensure that the temporary overvoltages that could occur are sufficiently limited so that their peak value does not exceed the relevant rated impulse voltage of Table F.1.
7 h# d" K* A# a# J8 W6 }) I( ]5 JNOTE 4 Examples of such equipment are those containing electronic circuits protected to this level, however see the note in 4.2.5.; u3 P$ f' K3 k( k4 f* J
NOTE 5 Unless the circuits are designed to take the temporary overvoltages into account, equipment of overvoltage category 1 cannot be directly connected to the supply mains.
作者: amote2008    时间: 2008-1-16 17:12
那在29章中有说明,在微观污染环境为3级时,14章的瞬间过电压不用做,在附录M中,对污染等级的解释似乎有点模糊,请教大侠们 稍加解释!!
作者: fuyong    时间: 2008-1-17 22:39
我的理解是当电气间隙小于29章时,需要做14章的瞬间耐压,未击穿就可以判定通过,击穿就判不通过
作者: 0321    时间: 2008-3-7 14:16
引用第0楼amote2008于2008-01-16 15:42发表的 335标准的14章瞬间过电压 :% ~+ w. l* j% @* g, v5 g6 H- A
什么情况下,可以不做此实验啊 ?- l4 O0 X% b6 `& z
还有29章的过电压类别怎么判断啊 ?
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当电气间隙小于29章时,需要做14章的瞬间耐压测试;
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器具属于Ⅱ类过电压类别
2 ]5 t. y+ {) w, {! n8 R# ~注2:如果......可应用于Ⅰ类过电压类别
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8 X2 O0 ^) {0 A  [# r& L即是一般器具属于Ⅱ类
作者: rainTK    时间: 2008-3-7 15:23
29.1 Clearances shall not be less than the values specified in Table 16, taking into9 f. S2 m( Q/ d
account the rated impulse voltage for the overvoltage categories of Table 15, unless, for
8 i/ Y' r6 ^- d; i  S, u  T# dbasic insulation and functional insulation, they comply with the impulse voltage test of
( h1 `* x! B& _: o, UClause 14. However, if the construction is such that the distances could be affected by wear,! I5 r& ^& \+ P
by distortion, by movement of the parts or during assembly, the clearances for rated impulse5 Q. {9 _& B/ A& r( p+ e
voltages of 1 500 V and above are increased by 0,5 mm and the impulse voltage test is not
9 t7 F' b! p# b! U6 X0 Japplicable.
$ p3 d5 f) J: k' y# zThe impulse voltage test is not applicable when the microenvironment is pollution degree 3 or
# w$ M5 {* O5 c6 H+ ?' v' u) ufor basic insulation of class 0 appliances and class 0I appliances."  @2 k( W0 j' f( x1 a
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14章对功能绝缘和基本绝缘适用,电气间隙过不了,一般认证机构不会去做14章的。直接就failed了5 ~' ~, b5 A# x! R
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污染等级, 一般暴露在外面, 有电机。 的部位一般判3类4 R7 O0 ~. p+ g/ H/ O8 J
有一定的密封, 一般不会有灰尘进去就可以判2类。
2 ~/ c0 O, @8 Z! [  b8 b- F1类一般很少判, 除非象继电器一样完全密封的才看作1类。
作者: wiltoncou    时间: 2008-3-9 20:27
先回答LZ的问题:7 ~) l. e$ b! Y+ L
1、只要电气间隙能符合19章的都不用做14章的试验。
' }: n3 N+ R# M4 ]" _3 }! W( H0 }2、对于家电,看29章,明确说明,器具属于过电压类别II。
( H3 W& @; X9 p0 v0 @对于14章,是新版335标准对电气间隙不符合要求的一项测试,但大家要注意,不是所有的电气间隙不符要求都可以通过这项测试来豁免,只有基本绝缘(除0类及0I类器具或非3级污染)和功能绝缘才行,附加绝缘和加强绝缘是不允许的。附上60335之A2附录L图L.1给大家参考。
+ [" o/ `" \. t. p7 R7 Z: n [attach]17820[/attach]; S% Z& U1 r1 d! K: Q" w; k( r
大家要切记有两种方法来救29章:14章和19.11.2a),但14章只针对电气间隙,而且是 基本绝缘(除0类及0I类器具或非3级污染)和功能绝缘的电气间隙,19.11.2a)是针对爬电距离的电气间隙,但只针对功能绝缘。使用时务必小心。




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