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+ X: l$ d8 L4 ^/ D0 r1) In case of components mounted on a printed wiring board (PWB) and placed across safety
/ g: [$ p* g g. c5 S+ [( Y& Oinsulation (e.g. reinforced insulation), how to deal with different requirement both for printed wiring K9 i7 k! U/ |( K5 h
material and different group of materials?
% R/ A0 f9 c# D* k l0 p2) In case of components mounted on a printed wiring board (PWB) and placed across safety# @3 ~' K$ g. Y! j: H8 D
insulation (e.g. reinforced insulation), how to deal in case of different material group for PWB and- _8 L$ I: Z5 e8 W4 {1 H( Q4 h
components placed on it (e.g. PWB of material group I and relay base of material group IIIa)?' w( ^5 K5 K( z k2 U2 \
5 p& L- }* R: y6 @: _, mDecision
: M4 [( o8 r8 E5 b, A1) Column relevant to printed wiring material in micro-environment of pollution degree 1 and 2 can
4 }5 W$ R7 { A, I( o$ a2 \only be used when there are no components placed on the PWB, across the investigated insulation.
' G. v( R+ b5 b+ rIn this case, the column showing the worst case has to be used.$ c! n& j9 t+ S' y& @
2) In case of different material group both for PWB and components, column showing the worst case
( X8 u) k' C4 R/ W& E7 ^3 phas to be used.
- ?9 W. F& R9 [) BRemark: For the scope of these decisions, a component is considered to be in contact with the PWB
) _, C7 N* F+ T Q/ eif the surface of the component is located at a distance less than the “X” value indicated in table of
5 E8 W4 A1 e2 W5 |annex B. See enclosed drawings
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