|
4 T" X3 ^7 u6 ~2 Q+ R7 k& ]3 a0 K6 u2 r2 }1 a# O
1) In case of components mounted on a printed wiring board (PWB) and placed across safety: c) t( e) c( d: w
insulation (e.g. reinforced insulation), how to deal with different requirement both for printed wiring
2 t; L- H; m+ Y# W& m) Bmaterial and different group of materials?
# Q& U9 f7 u% g6 K+ L2) In case of components mounted on a printed wiring board (PWB) and placed across safety6 [7 q/ u2 b2 ^# J- i- t) ~
insulation (e.g. reinforced insulation), how to deal in case of different material group for PWB and& g+ |" S* J7 Z T- d i y
components placed on it (e.g. PWB of material group I and relay base of material group IIIa)?
$ Z/ p) P$ u) ~. `# m9 E z
9 k G% @$ w# w4 J6 E3 Y3 v" U3 oDecision
5 q; H0 y# d7 d+ L) ?1) Column relevant to printed wiring material in micro-environment of pollution degree 1 and 2 can
; x* d9 V6 G* | D0 [2 l) Yonly be used when there are no components placed on the PWB, across the investigated insulation.
) C' m( U: B" f ZIn this case, the column showing the worst case has to be used.; h3 h S6 c: L' X3 O( _5 c
2) In case of different material group both for PWB and components, column showing the worst case4 G: Y8 q. k/ B' ~. n5 t1 z w( V' L
has to be used.
( d& Z: k( g) |* q6 y. ]4 TRemark: For the scope of these decisions, a component is considered to be in contact with the PWB
. S' {1 B |' i- l" W% M2 \. ^: tif the surface of the component is located at a distance less than the “X” value indicated in table of+ E6 S3 c6 u% O9 s
annex B. See enclosed drawings
1 C# |8 w5 Q9 Z: ^* H: f3 e; O& \ G2 u, R4 F
5 Y8 @* s* U3 o: i0 [- e6 h |
本帖子中包含更多资源
您需要 登录 才可以下载或查看,没有账号?注册安规
x
|