Distribution Rack Requirements B-3
Figure B-1 Recommended Service Access
Mechanical Requirements for the Rack
Verify that your racks comply with the standards and
requirements in your cabling system plan and
conform to these conventional standards:
■In the United States, comply with EIA Standard
RS-310C: Racks, Panels, and Associated
Equipment.
■In countries other than the United States, comply
with IEC Standard 297: Dimensions of Panels and
Racks.
In addition, 3Com recommends that your distribution
racks meet these requirements:
■Use an open style, 19-inch rack. The rack styles
shown in Figure B-2 facilitate easy maintenance
and provide excellent ventilation.
■Use a rack that has the universal mounting rail
hole pattern identified in IEC Standard 297. See
Figure 2-3 for a description of the universal
mounting hole pattern.
■Use a rack that is made of steel.
■Install equipment in the lower half of the
distribution rack to avoid making it top heavy.
■Use a rack that supports approximately 272 kg
(600 lb)
■Use a rack that has adequate electrical grounding,
for instance, with a distribution rack grounding kit.
■Verify that the floor under the rack is level within
5 mm (3/16 in.). Use a floor-leveling cement
compound or bolt the racks to the floor.
■Attach the rack to the wiring closet floor with
9.5 mm (3/8 in.) lag screws or equivalent hardware.
■Brace open distribution racks if the channel
thickness is less than 6.4 mm (1/4 in.).
76 cm (30 in.)
76 cm (30 in.)