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EN60950-1:2006
$ V; Y# I& M" @( m9 i4 p0 }9 y4.2.7 Stress relief test* g" d) ]! y, [8 i) e0 Q) Z5 P$ }
ENCLOSURES of moulded or formed thermoplastic materials shall be so constructed that any
i' h* r1 C! y/ d, o4 ^shrinkage or distortion of the material due to release of internal stresses caused by the
2 o5 i" [6 y8 i' S1 U8 ?/ |moulding or forming operation does not result in the exposure of hazardous parts or in the( F/ H" Y9 H3 y% s2 k- b
reduction of CLEARANCES or CREEPAGE DISTANCES below the values specified in 2.10 (or
) Z9 w- X4 e5 [0 b, }Annex G).
! U6 Y. O( R/ O6 t+ XCompliance is checked by the test procedure described below or by the inspection of the
J- o5 J' n' M& Aconstruction and the available data where appropriate.
7 C3 B9 f& j+ k; EOne sample consisting of the complete equipment, or of the complete ENCLOSURE together
9 v) e2 @+ V7 E; [/ _6 q o+ m7 C Gwith any supporting framework, is placed in a circulating air oven (according to2 k$ S, c" L* \; s
IEC 60216-4-1) at a temperature 10 K higher than the maximum temperature observed on the
6 F1 u$ ?2 t! ?5 MENCLOSURE during the test of 4.5.2, but not less than 70 ° C, for a period of 7 h, then permitted4 y! Z3 p- `3 S9 v
to cool to room temperature.. B( O2 U' l* d
With the concurrence of the manufacturer, it is permitted to increase the above time duration.
a q2 w) E( N/ ]& A! o ]For large equipment where it is impractical to condition a complete ENCLOSURE, it is permitted
' ~7 a/ X( X3 T, ato use a portion of the ENCLOSURE representative of the complete assembly with regard to4 {* {% k) M& s7 F: H3 H) ~5 @$ i
thickness and shape, including any mechanical support members.! l6 W& p$ z" K& T% a
NOTE Relative humidity need not be maintained at a specific value during this test.; f3 s3 n3 M* G% |, ^5 R6 @$ `
If the above test is conducted, the compliance criteria of 4.2.1 apply. |
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