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1) In case of components mounted on a printed wiring board (PWB) and placed across safety
9 _( Q- U0 x5 ?& _1 ^insulation (e.g. reinforced insulation), how to deal with different requirement both for printed wiring$ Y7 ~; l. `' W) g
material and different group of materials?0 W6 |* y9 n! J
2) In case of components mounted on a printed wiring board (PWB) and placed across safety% X5 z/ J9 @4 o) ~4 @
insulation (e.g. reinforced insulation), how to deal in case of different material group for PWB and! f7 r4 @1 g8 k' Y
components placed on it (e.g. PWB of material group I and relay base of material group IIIa)?
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Decision' I: E1 g5 H8 |5 f7 K) S
1) Column relevant to printed wiring material in micro-environment of pollution degree 1 and 2 can( [6 n6 u! a! Z |: l' y
only be used when there are no components placed on the PWB, across the investigated insulation.3 U ~+ B6 o+ l5 X( R! r
In this case, the column showing the worst case has to be used.( k) g; B, \4 i" w
2) In case of different material group both for PWB and components, column showing the worst case
2 |1 Q: f7 R0 [) S- i& P. a& ]has to be used.( g7 J$ b5 t% L* L$ f5 C+ Y5 m3 {
Remark: For the scope of these decisions, a component is considered to be in contact with the PWB T+ z8 G, ]& Y- j! Q
if the surface of the component is located at a distance less than the “X” value indicated in table of3 D0 r9 W9 i4 x+ C
annex B. See enclosed drawings
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