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5.5.2. Operating Tests
5.5.2.1. Cold Operation Test
Parameter Test Method and
Conditions
Duration Evaluation Standard
Cold Operation Test
(Ref. EN 60068-2-1)
-20°C
rel. humidity not
controlled
signal acc. Chapter 3.3
72h Measurements after 2 hours
recovery time.
All samples fully operable.
THD and resonance may be
increased after test. All other
acoustical parameters
according specification with
tolerances increased by 50 %.
5.5.2.2. Heat Operation Test
Parameter Test Method and
Conditions
Duration Evaluation Standard
Dry Heat Operation
(Ref. EN 60068-2-2)
+70°C
rel. humidity not
controlled
signal acc. Chapter 3.3
500h Measurements after 2 hours
recovery time.
All samples fully operable.
THD and resonance may be
increased after test. All other
acoustical parameters
according specification with
tolerances increased by 50 %.
5.5.3. Salt Mist Test
Parameter Test Method and
Conditions
Duration Evaluation Standard
Salt Mist
(Ref. IEC60068-2-52,
Kb / Severity 2
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.
Component may have reduced
performance, but must still
function properly. The allowable
sensitivity difference shall not
be greater than ±3dB from
initial sensitivity.
