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29.1 Clearances shall not be less than the values specified in Table 16, taking into' j4 ]' @) |+ L" T
account the rated impulse voltage for the overvoltage categories of Table 15, unless, for
4 K1 ^( _, Y( G* p" L- V9 `; mbasic insulation and functional insulation, they comply with the impulse voltage test of
# I/ v8 s1 g$ @& B+ lClause 14. However, if the construction is such that the distances could be affected by wear,
* j: G" k6 o Mby distortion, by movement of the parts or during assembly, the clearances for rated impulse
' W/ p+ s/ }! p; D+ j! s) kvoltages of 1 500 V and above are increased by 0,5 mm and the impulse voltage test is not
( J$ D- p* o5 F% }0 C$ U! p& Yapplicable.
, z/ H! d9 v( B+ \' `7 l2 D+ \The impulse voltage test is not applicable when the microenvironment is pollution degree 3 or
6 h; j! c' n; Y. O3 v9 M1 Y# o: Wfor basic insulation of class 0 appliances and class 0I appliances."
" j' a- b# p& [8 Z9 [3 w* `. `" W) T' w9 U+ r( Z9 \
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
2 I5 n) |4 V5 D- ^4 R
+ f5 k5 q, R- N污染等级, 一般暴露在外面, 有电机。 的部位一般判3类
3 J; h% x- L, o5 ~, O有一定的密封, 一般不会有灰尘进去就可以判2类。8 f3 y$ P( d" J/ z: o1 y" w
1类一般很少判, 除非象继电器一样完全密封的才看作1类。 |
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