Siemens SINAMICS S120 Equipment Manual page 23

In the cabinet, a fan is installed above the power sections. To optimize usage of the external
air heat sink, it is best to arrange the components in such a way that the heat is dissipated
equally over the surface of the external heat sink. This means that, if possible, a large power
section should be situated next to a smaller one. The current carrying capacity of the DC link
busbars must be taken into account here.
Rear view of cabinet
Figure 2-2 Rear view of cabinet
In this example, two axial fans with a diameter of 150 mm ensure forced convection. The
ribbed heat sink, which is attached to the rear, is located in an air duct (approx. 150 mm
deep). Additional air guides on the sides improve air guidance and significantly optimize the
cooling process for the power sections.
Equipment Manual Booksize Cold-Plate Power Sections
Manual, (GH4), Edition 06.2005, 6SL3097-2AJ00-0BP2
Cold plate with external air heat sinks
2.2 Example: cold plate with external air heat sink
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