Table 19. Supported Rack Types; Figure 10. Static Rails - Dell PowerEdge R820 Technical Manual

The static rails (shown in Figure 10) support a wider variety of racks than the sliding rails but do not
support serviceability in the rack and are therefore are not compatible with the CMA.
One key factor in selecting the proper rails is identifying the type of rack in which they will be
installed. Both the sliding rails and the static rails support tool-less mounting in 19"-wide, EIA-310-E
compliant square hole and unthreaded round hole four-post racks. Both also support tooled
mounting in threaded hole four-post racks, but only the static rails, as the more universal solution,
support mounting in two-post (Telco) racks.
Table 19 lists the rack types that the R820 supports. The R820 is not compatible with any other Dell
rails or CMAs including previous generation rails.
Rail
Product
identifier
B6
R820
B4
Other key factors governing proper rail selection include the spacing between the front and rear
mounting flanges of the rack, the type and location of any equipment mounted in the back of the
rack such as power distribution units (PDUs), and the overall depth of the rack. Due to their reduced
complexity and lack of need for CMA support, the static rails offer a greater adjustability range and a
smaller overall mounting footprint than the sliding rails.
For detailed information about static and sliding rails, see the Rack rail specifications section in
Appendix A. For more information on installing the R820 in a rack, see the
Instructions
on Dell.com/Support/Manuals.
34 PowerEdge R820 Technical Guide

Figure 10. Static rails

Table 19. Supported rack types
Mounting interface
ReadyRails II
ReadyRails
Rack types supported
Rail type
4-post
Square Round
 
Sliding
 
Static
2-post
Thread Flush Center
 X X
  
Rack Installation