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本帖最后由 小米 于 2012-11-8 21:04 编辑 ! J5 W O* Q9 U6 F% H. x& q
- Y, T" U: r: ] | | DSH 717& u: ]2 k9 G9 \/ Q; J: x
| Creepage and clearance determination, groove, recess, corner, bridging of distance X8 O. s, j3 O o7 x+ S6 {% N
| 4.2, 6.2
% f4 t) Z* i/ c5 ]" b, W* [ | 60664-1(ed.1.2) & 60065-1(ed.2) & All equipment standards based on these) c; E" Y c1 t4 W' i2 s
| 0 W- Z0 z% e" x& s) o( G& M
Standard(s): No. Year
& ^/ h4 D# s5 }! T* kIEC 60664-1/2002 ed1.29 P+ }* _$ S) _3 j2 `# E: z$ I0 E5 E
IEC 60664-1/2007 ed2.0
) ~# J4 n1 W+ P; g0 J3 R" nAll equipment standards/ H2 n3 J! |9 O& S/ J% ~1 h1 U' u
based on these
& d* d" H+ ]8 ~# K+ U2 [DSH& X5 a5 \5 p3 G6 g" w
07178 v$ d5 k7 D3 [9 [8 \
2008
y7 i: [! h; g1 mCategories:
# Z$ {, x+ D3 }# fVarious, General
! B9 A) \6 J* \( K0 R4 mSubclause(s): e& ^. C' M+ k
4.2. C# y& t: T, w9 W9 z& `& q9 L
6.2
( B. J' l$ q, F/ \Developed by:
p" f, J7 C5 |- }+ I, {) pWG2 - WG42 B# N9 f8 V; I7 v1 D; m- k( K
Subject:# |$ X+ B# j$ A L' | F
Creepage and clearance
& [7 _' B2 w1 @, ^2 d! `determination, groove,
9 c8 B; Z2 r4 K+ |6 G. Vrecess, corner, bridging# ?+ g5 U$ Z! b# J) Y
of distance X4 _$ h+ o; R8 z% x- m' Q2 P
Key words:
/ `; T- e" x7 }4 P; W# y& p! @- Creepage$ i8 }2 F* G* O( H& v; S! c" l
- Clearance3 ]. b: X- N9 J. \; A r$ N
- Groove
; K) O9 i, ]1 a0 X- l- Recess# u7 |3 ]# ` A
- Corner
. M7 P I; F W/ [- Bridging of distance
8 S* A8 s2 G, u6 }/ z+ zX: W: h$ c- }2 F- ~! P% E% f
Decision approved at the
O' S! i/ K- z9 D& b5 Z3 l2 P2009 CTL Plenary
/ ^- S7 _/ o1 DMeeting$ i" }4 X0 j, o
Questions:" ?4 }6 M! Y2 ~/ b9 G: A. O' u ]
1) How shall the examples given in IEC 60664 be interpreted for intermediate situations?: V" f9 g9 R& q: a% {! a0 p* v
2) How shall the example given below be judged correctly, based on the examples given in, b8 j, `; {4 p
IEC 60664-1 and based on the assumption that X = 1 mm?& d7 A w+ ^& }. }: `- z
0,8mm! `8 U+ _" W+ M6 X, |, s
2 mm2 J+ N& i# W7 }/ {1 J
PCB6 N, Q- R( Z8 G% h, X+ Y: p
PCB-Track (ending on the
: S. O, Y9 B& ]+ c4 aedge of the cut-out
- _! @1 c: [+ ?* B3) When shall the sentence:, G1 N! L" ~ V) ~8 i
“If the associated clearance is less than 3 mm, the minimum dimension X may be reduced to& x0 T# _* R$ u' n
one third of this clearance.” be applied?3 }, L7 T3 x0 R$ _2 o' x; a
Does this sentence refer to the actual clearance measured or to the minimum clearance8 ]3 M$ Q# U4 d* o/ q
required?! R( C- |$ S7 E" p: b. m
Decisions:( p! t) o. z. r$ v
Ad 1)
2 i* F. `7 @! o9 Z% v" E( g* XAn intermediate situation not covered directly by the Standard shall be determined by) q% r5 N4 Y* ]9 p( l
considering it as an extension of the most appropriate example from the Standard. An example2 |2 ?- g0 r3 W3 O- z
of the methodology is given in the Explanatory Notes to Question 2."
7 P7 `6 A% M3 N; M' ]! l% sAd 2)
! {5 ?6 s6 q$ lThe example shall be judged without any bridging of the corner in the cut-out
?( X8 I8 {, H, q8 ] creepage = 2,8 mm, no shortcut applicable.
' l: q1 m6 W! lAd 3)
/ H9 I6 p3 a0 b* U+ J, yThe sentence shall always be applied whenever the required clearance is less than4 \, c$ t. G0 o; X5 U- @4 Z( v
3 mm and the allowed reduction of the minimum dimension X shall be referred to 1/3 of the
* t) m* P/ v6 }, Mrequired minimum clearance. R, l% O% U- L3 X3 m, r6 ~6 k
5 A5 U, X3 ?4 L+ ~1 m5 w
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