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有没有人知道如下条款中说提到的电压梯度的峰值如何检测?有没有实例说明怎么将这个条款应用到线路板上呢?谢谢!, i3 ]' M$ _8 V0 j8 {
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: e6 j2 Y2 y3 B6 s1 fFor conductive patterns on printed circuit boards, except at their edges, the values in the
3 \+ O8 E# y5 {' ^( Jtable between parts of different potential may be reduced, as long as the peak value of the# x5 F# ~/ D- P+ }( P9 c
voltage stress does not exceed:
0 m$ o4 l9 w+ T1 l) v# g# B– 150 V per mm with a minimum distance of 0,2 mm, if protected against the deposition of dirt;
; G$ w( B& @( y8 U" T( f– 100 V per mm with a minimum distance of 0,5 mm, if not protected against the deposition of5 P: K, p( g$ h& g/ `; F6 n4 `3 v
dirt.4 {2 ~# z0 i& m0 l& a4 V5 `& f
When the limits mentioned above lead to higher values than those of the table, the values of# G; y9 G0 k9 n5 b E4 V
the table apply.
* Q9 \2 b0 ~; h. `: _6 OFor peak voltages exceeding 50 V, the reduced creepage distances only apply if the Proof
" r0 n' T# C# u7 z. A, pTracking Index (PTI) of the printed circuit board, measured as in Annex G, is greater than
0 q0 x+ u+ ]6 w% X' R- s' A; j. d175.& K g8 j3 F) {8 E v
These distances may be reduced further, provided that the tool complies with the6 x2 N. u' v4 P3 e
requirements of Clause 18 when the distances are short-circuited in turn.
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# a5 J' o6 J1 g1 t+ I1 o+ T, ?4 R对印刷电路板上的导电图形,其边棱除外,只要电压梯度的峰值没有超过下述值,表中关于不同极性部件间的值可以减小. s% a9 P# e# ?7 a, W
——若是防尘物沉积的,为150V/mm,但最小距离为0.2mm.
$ Z, U4 B0 h! u( m ——若不是防尘物沉积的,为100V/mm,但最小距离为0.5mm.
/ d" w& D" N6 h 对峰值电压超过150V的情况,只有印刷电路板的耐漏电起痕指数(PTI)按照附录G进行测量时超过175,减小的爬电距离规定才适用.. ^+ M+ U( r- z2 q) ~/ u0 ? H
只要当这些距离轮流短路时,器具符合19章的要求,这些距离可以进一步的减小. |
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