Floor loading examples

The following tables provide estimated floor loading values for the various system configurations of CPC and PCIe+ I/O drawers.

Floor loading is a function of system weight, system area, clearance area around the system, and system installation environment (raised or non-raised floor).

Attention: Due to system weight and machine area variability, the following tables cannot cover all of the possible system configurations. The following tables provide the absolute limits of floor loading for a system that meets the requirements for operation and serviceability.

The provided floor loading values are for installed systems. Systems that are surrounded by other equipment, such as in storage, can exceed a floor loading of 976 kg/M2 (200 lbs/ft2).

  • The minimum floor loading values are for a stand-alone installation with 5 ft of clearance space all the way around the system. This scenario assumes that the floor is a non-raised floor (15 lbs/ft) and a maximum exterior clearance of 5 ft.
  • The maximum floor loading values are for a system that is being installed in the middle of an existing row. This scenario assumes that the floor is raised floor (25 lbs/ft), there is no side clearance area, a 3 ft hot aisle (rear), and a 4 ft cold aisle (front).
The system weight that is used to calculate the following floor loading values (minimum and maximum) assumes that all of the drawers are maximum plugged. The weight in each instance is the maximum.
Note: The Earthquake Kit hardware weighs approximately 43 kg (95 lbs). If this feature is ordered, you must add the following:
  • 2.3 kg/M2 (5 lbs/ft2) to the maximum floor loading values
  • 1.5 kg/M2 (3 lbs/ft2) to the minimum floor loading values
The following formula is used to calculate the floor loading values and is provided for your reference. You can use this formula to obtain the floor loading (FL) values for your specific system configuration.
FL (lbs/ft2) = k + (w - 120 * n) / ((4 + a + d)*(2 * n + c + b)) 
  • k = 25 (raised floor environment) or 15 (non-raised floor environment)
  • w = System weight (lbs)
  • n = Number of frames (1, 2, 3 or 4)
  • a = Left side clearance dimension
  • b = Front clearance dimension
  • c = Rear clearance dimension
  • d = Right side clearance dimension

See Weight distribution and floor loading for sample floor loading figures of the 3931.

PDU power

Figure 1. Floor loading for PDU powered system
This graphic shows a sample floor loading values for a PDU powered 3931.

BPA power

Figure 2. Floor loading for BPA powered system
This graphic shows a sample floor loading values for a BPA powered system (radiator-cooled).