Installing the S7-400

Example of selecting the cabinet type

The example below clarifies the maximum permissible ambient temperature at a particular power loss for various cabinet types.

Equipment suitable for installation in a cabinet:

1 central rack

2 expansion racks, 150 Watts each

1 load current power supply under full load

Accumulated power loss

150W

300W

200W

650W

Permissible ambient temperatures at an accumulated power loss as shown in Figure 2-2:

Type of Cabinet

Max. Permissible Ambient

 

Temperature

 

 

Closed, with natural convection and forced circulation

(no operation possible)

(Curve 3)

 

 

 

Open, with through-ventilation (Curve 2)

approx. 38° C

 

 

Closed, with heat exchanger (Curve 1)

approx. 45° C

 

 

Cabinet dimensions

Vital dimensional design factors for an S7-400 cabinet

Space requirement of the racks

Minimum clearance between racks and cabinet walls

Minimum clearance between racks

Space requirement of cable ducts or fan subassemblies

Locations of rails

2-28

Automation System S7-400

Hardware and Installation

 

A5E00850741-01

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Image 44
Siemens S7-400 Example of selecting the cabinet type, Cabinet dimensions, Type of Cabinet Max. Permissible Ambient