Siemens S5-135U/155U - Manual (Page 65)

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System Manual
C79000-G8576-C199-06
3.7.5 Determining the Power Dissipation of Modules
The power dissipation of the modules can be found in the technical
specifications of the catalogs or manuals. If these values are not yet
incorporated in the technical specifications, they can be easily calculated
from the current consumption. The value of current consumption must be
multiplied by the corresponding voltage value.
Examples
CPU 928B Current
consumption 5A/5V
Ù Power dissipation = 25 W
CP 143 Current
consumption 4A/5V
0.5A/15V
0.04A/24V
Ù Power dissipation
approx. 21 W
IM 304 Current
consumption 1.5A/5V
Ù Power dissipation = 7.5 W
Installation Guidelines