Caution
Modules with a hard disk drive can only be used at an ambient
temperature of up to 50
o
C.
3.7.4
Examples for Determining
the Type of Cabinet
T
he following example shows the maximum permissible ambient
temperature with various cabinet types and the same power dissipation.
Example
The following equipment configuration is given:
1
Central controller
200 W
2
Expansion units, 250 W power dissipation each
500 W
1
Load PS, 24 V/40 A, 6EV1 362-5BK00 (full load)
200 W
Total power dissipation
900 W
F
rom Figure 3-16, with a total power dissipation of 900 W, the
maximum ambient temperatures given by the table are as follows:
Cabinet Design
Max. Permissible
Ambient
Temperature
Closed, with natural convection and
forced circulation (Curve 3)
(Operation not
possible)
Open with through-ventilation (Curve 2)
Approx. 33
o
C
Closed, with heat exchanger (Curve 1)
Approx. 42
o
C
Selection and Installation of Cabinets with SIMATIC S5
System Manual
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C79000-B8576-C199-03
