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8 rules for creepage distance and clearance: t5 P. n, C% M+ L5 x; |# b$ O; s& c
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1. A groove may have parallel, converging or diverging sides." V2 R; M! H+ Z! G* ~
2. Any groove having diverging sides, a minimum width exceeding 0,25 mm, a depth exceeding 1,5 mm and a width at the bottom equal to or greater than 1 mm, is regarded as an air gap.
/ @! a" V" I1 {7 P7 y# k3 Q3 w3. Any corner including an angle less than 80° is assumed to be bridged with an insulating link of 1 mm width (0,25 mm for dirt-free situations) moved into the most unfavourable position./ x7 V3 w# l B* I+ x
4. Where the distance across the top of a groove is 1 mm (0,25 mm for dirt-free situations) or more, no creepage distance exists across the air space .9 R& F# |! n, D! ?5 c$ @
5. A creepage path is assumed not to exist if there is an air gap as defined in item 2 above exceeding 0,25 mm.
! p" V* z+ d$ p6. Creepage distances and clearances measured between parts moving relative to each other are measured when these parts are in their most unfavourable stationary positions.
" u& z" i- x% o b7. A computed creepage distance is never less than a measured clearance.6 f, S6 C4 r r9 [. `
8. Any air gap less than 1 mm wide (0,25 mm for dirt-free situations) is ignored in computing the total clearance. |
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