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EN60950-1:2006
1 J. f4 F/ \ [3 _4 z4 Y; P) p4.2.7 Stress relief test
( u, v# C3 a8 k8 V+ T7 i# {ENCLOSURES of moulded or formed thermoplastic materials shall be so constructed that any: m* c, j: W) S% ^6 a
shrinkage or distortion of the material due to release of internal stresses caused by the% E* W( a8 ^8 x; ?( _4 R
moulding or forming operation does not result in the exposure of hazardous parts or in the
! _# H# `. ^! w. H, ]1 E+ \reduction of CLEARANCES or CREEPAGE DISTANCES below the values specified in 2.10 (or+ g. ^* u: y. s2 X, i- j; f
Annex G).
, o0 \8 q* \* c. rCompliance is checked by the test procedure described below or by the inspection of the
) y+ b" l, d! H6 Zconstruction and the available data where appropriate.. X0 X9 [+ W$ p3 y* o) P# I" q
One sample consisting of the complete equipment, or of the complete ENCLOSURE together+ W0 }" [/ ^9 x
with any supporting framework, is placed in a circulating air oven (according to
) w; h9 ?0 A* _) f8 s3 K: N6 HIEC 60216-4-1) at a temperature 10 K higher than the maximum temperature observed on the6 X3 j; k2 b3 b0 [) K
ENCLOSURE during the test of 4.5.2, but not less than 70 ° C, for a period of 7 h, then permitted
/ g" O4 b" f/ j3 o3 x- u; @4 L. Q( Xto cool to room temperature.
' y+ |3 l) \7 LWith the concurrence of the manufacturer, it is permitted to increase the above time duration.( C, {+ o$ R: u) U
For large equipment where it is impractical to condition a complete ENCLOSURE, it is permitted/ O: ^5 q! G+ p+ b
to use a portion of the ENCLOSURE representative of the complete assembly with regard to
% ^( d5 r. g) z: e5 B1 ^thickness and shape, including any mechanical support members.
+ Y( F1 T% x9 V9 f2 fNOTE Relative humidity need not be maintained at a specific value during this test.- o/ n7 s# X% z: N) u
If the above test is conducted, the compliance criteria of 4.2.1 apply. |
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