标题: DSH 2001 [打印本页] 作者: chinatown 时间: 2017-1-7 22:05 标题: DSH 2001 Question# z& H9 f4 L% E, G- |
1) In case of components mounted on a printed wiring board (PWB) and placed across D' l b' v8 o9 J9 T* m$ w(bridging) insulating distances on the PWB (e.g. providing basic or even reinforced insulation), ' `7 k% Z) f* @/ A# ~4 g- Lhow to deal with the different distance requirements for distances on the printed wiring& ? G4 b; R* A0 E2 Z1 Q
material and for distances on other plastics e.g. the housing material of the component, H" A P M1 x) o. X2 Z8 L
(depending on the applicable material group)? # Z6 V* g5 V$ k* a: Y# q* G" e; n9 k2) In case of components mounted on a printed wiring board (PWB) and placed across / w- \) j1 q% B* G9 T1 E, h3 G$ `0 |insulating distances on the PWB (e.g. providing basic or even reinforced insulation), how to , Z$ B6 H' A, W$ D; Gdeal with the different distance requirements, if the material group for PWB and for the! I8 E( b) M6 t, g
components placed on it is not the same (e.g. PWB of material group I and relay base of* o$ h, J& g; L
material group IIIa)?& z+ i" a t$ N7 ]+ u X
Decision1 e$ D2 }1 I5 ?
1) The defined reduced values for the required creepage distances relevant to printed wiring 3 t: r6 W3 ?6 A& Q7 K8 q7 vmaterial in micro-environment of pollution degrees 1 and 2 may only be applied when there # R+ @# `! c; q h2 b4 v. gare no components bridging the investigated insulation. If components are bridging insulating 6 ?6 M7 {8 |4 I8 J$ b* U0 wdistances on the PWB, the creepage distance requirements relating to the (component) 4 m. y& \4 y1 Q/ Zmaterial representing the worst case has to be applied for the PWB also. 8 P: v4 q* T" V% r2) In case of different material groups for the PWB and the components, again the requirement! i9 K7 R8 p) `% f1 Q& u
relating to the material representing the worst case has to be used. 6 L& n# `) ?/ I! S4 \: u" P3 G- lRemark: A component is considered to bridge insulation on the PWB, if the surface of the ; X1 d) L% b- P2 N% M: Dcomponent is located at a distance less than the value “X” (e.g. according to IEC 60664 series) 6 s8 J: r5 g3 j# G8 Ufrom the isolating PWB surface. See also enclosed drawing. 6 @, h2 D1 X+ g, v, O% F6 l/ } 6 B) A% E; Z' v- E! q3 f5 ]3 r8 e A' Z; | 作者: chinatown 时间: 2017-1-7 22:06
DSH 2001附件