4.5.2.
Operating Tests
4.5.2.1. Cold Operation Test
Parameter
Test Method and
Duration
Evaluation Standard
Conditions
Cold Operation Test
(Ref. EN 60068-2-1)
-20°C
72h
Measurements after 2 hours recovery time.
All samples fully operable.
rel. humidity not
controlled
THD may be increased after test. All other
acoustical parameters according
specification with tolerances increased by
50 %.
signal acc. Chapter
2.10
4.5.2.2. Dry Heat Operation Test
Parameter
Test Method and
Duration
500h
Evaluation Standard
Conditions
Dry Heat Operation
(Ref. EN 60068-2-2)
+70°C
Measurements after 2 hours recovery time.
All samples fully operable.
rel. humidity not
controlled
The allowable change in sensitivity shall
not be greater than 3 dB. All other
acoustical parameters according
specification with tolerances increased by
50 %.
signal acc. Chapter
2.10
4.5.3.
Salt Mist Test
Parameter
Test Method and
Conditions
Duration
Evaluation Standard
Salt Mist
The part must be
subjected to 2 hours
spray of 5% NaCl
salt mist, at 35°C
then be left at 40°C
and 95% RH for 22h.
3 cycles The samples shall be washed after the test
with distilled water and dried at T< 50°C.
(Ref. IEC60068-2-52,
Kb / Severity 2
Component may have reduced
performance, but must still function
properly. The allowable sensitivity
difference shall not be greater than ±3dB
from initial sensitivity.
4.5.4.
Shock Resistance Test (Free Fall Test) - unprotected product
Parameter
Test Method and
Conditions
Conditions /
Sample size
Evaluation Standard
Mechanical shock
Drop of sample without
fixation of release plane
from a height of 1.5m
onto concrete floor.
Each 3 shocks
in both
Component may have reduced
performance, but must still
directions of the function properly. The allowable
(Ref. IEC60068-2-32
Ed), Procedure 1
3 axes.
sensitivity difference shall not
be greater than ±3dB from
initial sensitivity.
(18 drops in
total)
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