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Question: In § 4 of IEC 61048 and in § 3 of IEC 61049 rules for sampling plan are provided.
2 p u l- b1 T- dBeside the main rule, the following additional statement is given: “The capacitor with
& C" V) a" m! Wthe maximum capacitance per unit surface area shall also be tested if this ratio- R! |% o" |% y s# ^, k0 O
exceeds that of the maximum capacitance value in the range by 10% or greater.
- H2 L/ T+ g' T0 V) ^* j; [Similarly, the capacitor with the minimum capacitance per unit area shall also be
/ @6 [7 @6 `$ j: H. K' t# otested if this ratio is less than that of the minimum capacitance value in the range by0 T5 Q7 c6 U, H
10% or greater”. Nevertheless, the sampling plan is not well specified when the
) m3 w+ k& c9 {" jabove case occurs. How should be composed the final sampling for tests?" K& Y3 B( K6 x4 n3 u: Z6 ?% ^
Decision: For the time being to apply the following proposed solution:
( j7 n0 p5 p1 s0 _1 w' Y: O# W" ?4 w7 N& pWhen the above case occurs, each group referred to in § 11 of IEC 61048 or in § 4
, T" R5 ~4 |4 V0 H/ [7 b- |4 Zof IEC 61049 shall contain as nearly as possible equal numbers of capacitors of the& g, D# }7 \! a+ ~* B) j# u
highest capacitance and of capacitors with capacitance per unit surface area
* g: M U) R6 p5 ]. \3 f1 x/ fexceeding that of the maximum capacitance value in the range by 10% or greater.! ?/ P1 p3 p7 x/ B& S
Similarly, each of those groups, shall contain as nearly as possible equal numbers of! c: X8 @* r- _$ b/ y
capacitors of the lowest capacitance and of capacitors with capacitance per unit: s, p# g; U( O; U
surface area less than that of the minimum capacitance value in the range by 10% or% X1 z: Q+ v2 ?! w5 I/ A: Y
greater.' n8 r$ D5 t% e
Example – IEC 61048 - § 11 – self-healing capacitor.
/ z" G% u5 q1 }: w. a" hA sampling of 50 capacitors is required and according to the above decision they+ H/ J+ ]: ~+ x' C" \6 b- U' G! g J
shall be split as follows:7 V$ z8 P( b# C9 i3 q) b q
- 12 (13) capacitors of the highest capacitance in the range;; a' }' Q" n0 K
- 13 (12) capacitors with the maximum capacitance per unit surface area exceeding that of the+ M$ f4 T6 h& p# n8 X
maximum value in the range by 10% or greater;& y7 I" ]9 G- @0 {3 m7 G3 M" F% C* I
- 12 (13) capacitors of the lowest capacitance in the range;8 a8 y: D8 M0 T8 m9 d
- 13 (12) capacitors with capacitance per unit surface area less than that of the minimum9 o" N. d; f$ [
capacitance value in the range by 10% or grater.
; }, V; ?. [' b, @' x
) g% G9 n1 F. {2 S( t: ` |
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