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1) In case of components mounted on a printed wiring board (PWB) and placed across safety
& ^8 Y' n' l; X rinsulation (e.g. reinforced insulation), how to deal with different requirement both for printed wiring
& C! b! }6 \) @- P' imaterial and different group of materials?1 ]3 c X* v8 j
2) In case of components mounted on a printed wiring board (PWB) and placed across safety
; Q; a$ h5 r6 Binsulation (e.g. reinforced insulation), how to deal in case of different material group for PWB and8 z/ _8 f* t' G% j5 U" N
components placed on it (e.g. PWB of material group I and relay base of material group IIIa)?) d7 X9 ~, L. H3 B
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Decision
! |) u( q. ^8 W7 O6 h9 m, O1) Column relevant to printed wiring material in micro-environment of pollution degree 1 and 2 can
3 b, l1 G# A" v! f E; yonly be used when there are no components placed on the PWB, across the investigated insulation. x/ c5 L$ Q& R* [1 ^, j
In this case, the column showing the worst case has to be used.; [/ A4 A- K* x. z
2) In case of different material group both for PWB and components, column showing the worst case
5 b9 s; j$ N6 i7 ?0 B5 Nhas to be used.; M* r6 W9 L* A) V. X
Remark: For the scope of these decisions, a component is considered to be in contact with the PWB+ U' x; @# o. E8 ~' t
if the surface of the component is located at a distance less than the “X” value indicated in table of& B) w+ B, R& c; h/ ?7 Y, o8 U
annex B. See enclosed drawings
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