An insulating lining or barrier of vulcanized fiber or similar materials used where spacing does not
. C$ B# b& Z0 L- f: sotherwise comply with the requirement shall not be less than 1/32 inch (0.8 mm) thick, and shall be so
" O) X" T; w. Z; Zlocated that it is not adversely affected by arcing, except that vulcanized fiber not less than 1/64 inch (0.4 4 C, m5 {4 L3 \+ q3 p8 [1 k/ G
mm) thick is able to be used in addition to an air spacing of not less than 50 percent of the spacing
, U/ r, v& u, t" R+ V! frequired for air alone. 4 R- W# `& ~% p8 D" x$ S/ c
如果硬化纸板绝缘衬里、绝缘层或是相似的材料用于间距否则不会符合要求的情况下,这些材料不
I$ _1 C3 G. q. E) k- H+ X( W能小于1/32 英寸(0.8 毫米)厚,其位置也不能受发弧的不利影响,除非厚度不小于1/64 英寸(0.4 毫
; e @8 S+ s; T米)的硬化纸板可以另外应用于空中间距不小于只要求于空中的间距的50%。 # b1 p3 B7 l( J$ k' V9 U
例外:如果硬化纸板绝缘衬里、绝缘层或是相似的材料符合17.3 的规定,则不要求其符合这一要求。
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# d2 @! V4 v) P' t+ i4 _- J上面英文有点八股,很难理解?谁能告个例子讲下?如电路板与外壳之间隔了个硬纸皮样东西,厚度要按上面来吗?
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