Siemens SIMATIC Rack PC 840 V2 Operating Instructions Manual page 64

Maintenance and service
11.1 Removing and installing hardware components
Installing the fan
Notice
Always install a fan of the same type!
Caution
Ensure that the arrow on the fan points away from the fan bracket.
Fan mounting position
The figure shows the correct fan
mounting position. Note the direction of
the arrow!
11-10
Operating Instructions, Edition 05/2006, A5E00248055-04
SIMATIC Rack PC 840 V2