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1) In case of components mounted on a printed wiring board (PWB) and placed across safety
) b, j8 p2 `5 V: z$ Oinsulation (e.g. reinforced insulation), how to deal with different requirement both for printed wiring B: U. w+ T/ w6 |6 h6 \2 ]
material and different group of materials?
4 g# c! p! I% G# u0 F4 G4 \2) In case of components mounted on a printed wiring board (PWB) and placed across safety1 ]' n: ^' a4 b0 w- i' a4 n
insulation (e.g. reinforced insulation), how to deal in case of different material group for PWB and1 I* b+ i3 W# p. g5 Q- J
components placed on it (e.g. PWB of material group I and relay base of material group IIIa)?
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3 A/ d& c7 Z! \$ @+ x; Q/ C0 sDecision7 d5 l) w7 g& j% S: {! p
1) Column relevant to printed wiring material in micro-environment of pollution degree 1 and 2 can8 k, J6 @9 f: S6 |
only be used when there are no components placed on the PWB, across the investigated insulation.
" ~; A8 V: V0 L7 b" XIn this case, the column showing the worst case has to be used." z( N0 {. t1 p& ]
2) In case of different material group both for PWB and components, column showing the worst case, a: @2 P5 L- p1 y6 F' U2 G/ n
has to be used.( q# D: G5 |0 g! i! m
Remark: For the scope of these decisions, a component is considered to be in contact with the PWB
/ ]/ n9 J2 D, M- F- Xif the surface of the component is located at a distance less than the “X” value indicated in table of+ u0 ~. \7 ]3 [" @) n0 E- M1 w. S' U
annex B. See enclosed drawings2 L, t L! G1 v; P
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