|
EN60950-1:2006% r8 G% D5 b+ }, D1 ^! V( x3 m. \+ c
4.2.7 Stress relief test
$ F% ?5 [2 Q* s, H9 _' W: h- iENCLOSURES of moulded or formed thermoplastic materials shall be so constructed that any
* a7 S. R" n) P6 f$ L4 Y$ P* Gshrinkage or distortion of the material due to release of internal stresses caused by the
) g: |$ _- P6 u+ g' X+ qmoulding or forming operation does not result in the exposure of hazardous parts or in the
: _/ ?2 w( `+ U0 u5 C2 @1 i0 Wreduction of CLEARANCES or CREEPAGE DISTANCES below the values specified in 2.10 (or
+ L: t, x9 `' M- U) M; W: k% WAnnex G).
4 j9 ~! {, g5 R, L w( M6 oCompliance is checked by the test procedure described below or by the inspection of the5 [8 M5 v/ H3 k( i
construction and the available data where appropriate.
% ]7 o" G7 w/ k* |8 ]One sample consisting of the complete equipment, or of the complete ENCLOSURE together
6 j; f' d, L% p8 S' h+ mwith any supporting framework, is placed in a circulating air oven (according to
3 Z5 Z% l. L$ X' [IEC 60216-4-1) at a temperature 10 K higher than the maximum temperature observed on the6 ~: \( p+ D* X
ENCLOSURE during the test of 4.5.2, but not less than 70 ° C, for a period of 7 h, then permitted. I- S {, S9 S
to cool to room temperature.
! {1 ^% ?9 S/ fWith the concurrence of the manufacturer, it is permitted to increase the above time duration./ m$ E4 Y |- l5 r k! h
For large equipment where it is impractical to condition a complete ENCLOSURE, it is permitted
. _. ]: j! z, M. ?; W% @3 xto use a portion of the ENCLOSURE representative of the complete assembly with regard to
?+ t) x- p! j/ g8 y6 k9 mthickness and shape, including any mechanical support members.
! L% z/ K1 N% ENOTE Relative humidity need not be maintained at a specific value during this test.
/ f, D) ~% S* t% M' h2 n! C0 PIf the above test is conducted, the compliance criteria of 4.2.1 apply. |
|