Issue:
The question is asked if the stated load rating of a cabinet can be exceeded, and if so by how much. Is there any "wiggle room" in the load ratings? 

Product Line:


Environment:
All versions and serial ranges.

Cause:
An application may require a load rating slightly higher than the cabinet that's specified. 

Resolution:

The NetShelter load ratings are not to be exceeded. There is no "wiggle room" in the load ratings. 
All stated load ratings include only the weight of the equipment installed into the cabinet. The stated load ratings do not include the weight of the cabinet, pallet or packaging. 
For applications whose load ratings exceed those of the NetShelter SX there’s a new NetShelter cabinet with a higher load rating; the NetShelter SX3K: https://www.apc.com/shop/us/en/categories/racks-and-accessories/racks-and-enclosures/integrator-ready-racks/N-1yeks2t
The NetShelter SX3K cabinets have both Shipping Load and Dynamic Load ratings of 3500 lbs., and a Static Load rating of 4250 lbs.