Sample Application: Selecting A Cabinet; Power Loss Dissipated - Siemens SIMATIC S7-300 Hardware And Installation Manual

Permissible ambient temperatures ...
are found in the Appendix Ambient Conditions.
4.7

Sample application: Selecting a cabinet

Introduction
The sample below clearly shows the maximum permissible ambient air
temperature at a specific power loss for different cabinet designs.
Installation
The following device configuration should be installed in a cabinet:
• 1 central device 150 W
• 2 expansion devices, each with 150 W
• 1 load power supply unit, 200 W under full load
This results in a total power loss of 650 W.

Power loss dissipated

The diagram in the figure below shows guide values for the permissible ambient air
temperature of a cabinet with the dimensions 600 mm x 600 mm x 2,000 mm,
depending on power loss. these values only apply if you maintain the specified
installation and clearance dimensions for module racks (profile rails).
Ambient temperature
o
in C
60
50
40
30
20
Figure 4-6 Power loss dissipated
S7-300 Programmable Controller Hardware and Installation
A5E00105492-01
Closed cabinet with heat exchanger; size of heat
1
exchanger 11/6 (920 x 460 x 111 mm)
closed cabinet with
3
natural and forced
ventilation
with device fan
200
400 600
Cabinet with enclosed
2 ventilation by self-convention.
800 1000 1200
Loss of heat
Configuring
1400 W
4-13