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EN60950-1:2006
3 x m" p. E. A& N4 x- q4.2.7 Stress relief test$ s5 V: [% _! j, @3 p
ENCLOSURES of moulded or formed thermoplastic materials shall be so constructed that any/ H: Q# g( f$ x+ P1 y
shrinkage or distortion of the material due to release of internal stresses caused by the% C) ~1 d2 V6 v6 K
moulding or forming operation does not result in the exposure of hazardous parts or in the
# A9 u, g4 _% y3 a9 ^2 t2 vreduction of CLEARANCES or CREEPAGE DISTANCES below the values specified in 2.10 (or
0 i* M; b7 K5 p+ v2 hAnnex G).9 |: }9 h2 x4 o/ i: M$ r8 Y9 j5 t3 M7 \
Compliance is checked by the test procedure described below or by the inspection of the
7 }+ o1 V- A- S- e7 gconstruction and the available data where appropriate.% N( q/ @1 N8 C6 s' _; ~' @! G; g2 Q0 t
One sample consisting of the complete equipment, or of the complete ENCLOSURE together
. Z j) `* |% y: bwith any supporting framework, is placed in a circulating air oven (according to
' D# V* I) }, F- L2 Q5 ?2 D" H2 VIEC 60216-4-1) at a temperature 10 K higher than the maximum temperature observed on the% l4 _, y- R" t
ENCLOSURE during the test of 4.5.2, but not less than 70 ° C, for a period of 7 h, then permitted
, j2 e; H) w# k: N! `: N; Pto cool to room temperature.
/ X1 r# r+ N* i+ Z" ^With the concurrence of the manufacturer, it is permitted to increase the above time duration.$ }, |6 t$ c& p. I( A
For large equipment where it is impractical to condition a complete ENCLOSURE, it is permitted, [4 d6 B0 n% t: F6 n
to use a portion of the ENCLOSURE representative of the complete assembly with regard to
4 L a' a2 |6 Athickness and shape, including any mechanical support members. |6 w6 f5 ^; {! K9 v
NOTE Relative humidity need not be maintained at a specific value during this test.- _4 d- s. h0 `: Q
If the above test is conducted, the compliance criteria of 4.2.1 apply. |
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