Application Planning 
  4.4 Ambient and environmental conditions 
SIMATIC Box PC 627 
Operating Instructions, Release 05/2006, A5E00362052-03 
4-3 
4.4  4.4 Ambient and environmental conditions 
 
When you plan your project, you should make allowances for: 
•  The climatic and mechanical environmental conditions specified in the specifications 
given in your operating manual. 
•  At least 100 mm space should be left free around the ventilation slots, in order that the 
PC receives sufficient ventilation. 
•  Do not cover the vent slots of the device.  
•  The device together with its AC power supply fulfils the requirements for fire protected 
enclosures according to EN 60950-1. Therefore it can be installed without any additional 
fire protective covering. 
•  The device with DC power supply does not conform to EN 60950-1 in the area of its 
power supply connection; therefore the mounting must meet the requirements of a fire 
enclosure. 
•  Always observe the mounting positions permitted for this device. 
 
 
 
Warning 
If the systems are installed in a non-permissible fitting position, the approvals pertaining 
to UL 60950-1, UL 508 and EN60950-1 are no longer valid!