Rack Rails And Cable Management; Sliding Rails; Table 19. Supported Rack Types; Figure 9. Sliding Rails With Optional Cma - Dell PowerEdge T420 Technical Manual

9 Rack rails and cable management

The sliding rail system for the Dell PowerEdge T420 provides tool-less support for four-post racks
with square or unthreaded round mounting holes. Compared to the T610 sliding rails that required
the use of adapter brackets, the sliding rails for the T420 now offer support for threaded hole racks
with the ReadyRails II mounting interface.

Sliding rails

The ReadyRails II sliding rails for the T420 support tool-less mounting in 19"-wide, EIA-310-E
compliant square hole and unthreaded round hole four-post racks. The rails also support tooled
mounting in threaded-hole four-post racks and are available with or without the optional cable
management arm (CMA).
The rails ship in the tool-less mounting configuration, but can be easily converted to the tooled
configuration. The optional CMA can be mounted on either the left or right side of the sliding rails
without the use of tools for fast and easy deployment. The T420 is backward compatible with the
T610 rails and CMA. The T420 supports sliding rails only. Static rails are not supported. Mounting in
two-post racks is not supported.
Figure 9 shows the sliding rails with the CMA installed.
Figure 9. Sliding rails with optional CMA
Table 19 lists the supported rack types for the T420.
Table 19. Supported rack types
Rack Types Supported
Rail
Product Mounting Interface Rail Type 4-Post 2-Post
Identifier
Square Round Thread Flush Center
   X X
T420
C2 ReadyRails II Sliding
Screws are not included in the kit due to the fact that threaded racks are offered with a variety of
thread designations. Other factors to consider when deploying the T420 include the spacing
between the front and rear mounting flanges of the rack, the type and location of any equipment
33 PowerEdge T420 Technical Guide