Harman International Industries Inc MICROCORE Manual De Usuario

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XI
Appendix 1: Air Temperature and Humidity
General
Normal operation of the unit or system is warranted under the ambient condi-
tions defined by EN 60721-3-3, set IE32, value 3K3.
This standard consists of an extensive catalogue of parameters, the most 
important of which are: ambient temperature +5...+40 °C, relative humidity 
5...85% (i.e., no formation of condensation or ice); absolute humidity 1...25 g/
m³; rate of temperature change < 0.5 °C/min. These parameters are dealt with 
in the following paragraphs.
3 -
# #
Ambient Temperature
3 Z -
ture range (i.e. temperature of the incoming air) of +5 °C to +40 °C. When
rack mounting the units, the intended air flow and herewith adequate cooling 
must be provided. The following facts must be considered:
  -
ductor components is 0 °C to +70 °C (commercial temperature range for 
operation)
 
always cooler than 70 °C
  ?@‚
7B@‚
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air flow of 2.65 m³/min is required
9) 4
A rack dissipating P = 800 W requires an air flow of 0.8 * 2.65 m³/min which 
corresponds to 2.12 m³/min.
 $ %# #
failure or illumination with spot lamps), the outgoing air temperature must 
be measured directly above the modules at several places within the rack. 
The trigger temperature of the sensors should be 65 °C to 70 °C
Frost and Dew
The unsealed system parts (connector areas and semiconductor pins) allow 
for a minute formation of ice or frost. However, formation of dew visible to 
the naked eye will already lead to malfunctions. In practice, reliable opera-
tion can be expected in a temperature range above –15 °C, if the following 
general rule is considered for putting the cold system into operation:
If the air within the system is cooled down, the relative humidity rises. If it 
reaches 100%, condensation will arise, usually in the boundary layer between 
the air and a cooler surface, together with formation of ice or dew at sensi-
tive areas of the system (contacts, IC pins, etc.). Once internal condensation 
occurs, trouble-free operation cannot be guaranteed, independent of tempera-
ture.
-
mation of condensation or ice. Only with a minute formation of ice, direct 
Appendix