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本帖最后由 jansle_happy 于 2022-5-25 16:27 编辑
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/ Z1 B ]4 H) h/ W. R# E( m) z如题,请教大神怎么看UL294第32章节的爬电距离和电气间隙,他要求是非绝缘带电部件和相关非绝缘带电部件以及dead-metal部件之间爬电距离和电气间隙需要满足下表要求,但是看起来是所有非绝缘部件都需要看,不管电压是危险电压还是非危险电压,这个看起来不符合逻辑啊,一般safety的标准不是只会看危险电压么?另外,表格中有些电压段是有重复,比如other栏中有两个31-150V,但是给定的爬电距离和电气间隙又不同,到底要怎么看?
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32 General
7 }- k! A1 u7 y( C ], P32.1 Except as specified in 33.2, spacings between uninsulated live parts or between uninsulated live parts and dead-metal parts shall not be less than those indicated in 32.2 – 32.5.
1 n5 k8 l2 O X( Q4 N32.2 Where deformation of the enclosure is likely to reduce spacings, the spacings between an uninsulated live part and:$ P1 P7 a7 U+ b1 V) _$ K, Z
a) A wall or cover of a metal enclosure;6 y4 S% a. R1 j$ b3 X3 P! `4 x
b) A fitting for conduit or metal-clad cable; and
1 E5 _' D. s1 Y2 Q; A c) A metal piece attached to a metal enclosure, where deformation of the enclosure is likely to reduce spacings,: L0 R; D( A% R- N6 f3 L+ L
shall not be less than those indicated in Table 32.1. Also see Figure 32.1.
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32.3 The spacings between an uninsulated live part and:
+ l6 V9 ^3 X) s! H: a' M, k+ ? a) An uninsulated live part of opposite polarity,
' F' p$ A4 @/ R6 _( Z b) An uninsulated grounded dead-metal part other than the enclosure, and
0 s1 s- T& ~1 Q c) An exposed dead-metal part that is isolated (insulated),7 F# O- B5 J' X) Q1 D" e
shall not be less than those indicated in Table 32.1. See 33.1 – 33.4 for exceptions to this requirement.* s/ v$ k$ C- \$ ?9 Z
" j' W# E5 ^) r* m- E+ y32.4 If a short circuit between uninsulated live parts of the same polarity would prevent the intended operation of the product, the spacings between the uninsulated live parts shall not be less than those indicated for ″Other parts″ in Table 32.1.
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32.5 Film-coated wire is considered an uninsulated live part in determining compliance of a product with the spacing requirements, but film coating may be used as turn-to-turn insulation in coils.
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