5.5.2.
Operating Tests
5.5.2.1. Cold Operation Test
Parameter
Test Method and
Duration
72h
Evaluation Standard
Conditions
Cold Operation Test
(Ref. EN 60068-2-1)
-20°C
Measurements after 2 hours
recovery time.
rel. humidity not
controlled
All samples fully operable.
signal acc. Chapter 3.3
THD may be increased after
test. All other acoustical
parameters according
specification with tolerances
increased by 50 %.
5.5.2.2. 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.
rel. humidity not
controlled
All samples fully operable.
signal acc. Chapter 3.3
The allowable change in
sensitivity shall not be greater
than 3 dB. All other acoustical
parameters according
specification with tolerances
increased by 50 %.
5.5.3.
Salt Mist Test
Parameter
Test Method and
Conditions
Duration
3 cycles
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.
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.
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