Specifications

7-6 Cisco MGX 8220 Reference, Release 4.1
Rack Mounting the MGX 8220 Units
Vertical Positioning
The MGX 8220 units are mounted in a specific order from the bottom to the top.
The AC power module (if used) is mounted first, then the fan cooling assembly is mounted, then the
first shelf is mounted, and then the second shelf (if installed) is mounted.
If a third and/or fourth shelf is installed, a booster cooling assembly must be mounted immediately
above the second shelf and immediately below the third and fourth shelves. The plenum or spacer
unit is mounted last above the highest shelf. If a cable management kit is used in a 2 or 4 shelf rack,
the top unit must be a Plenum because cable management hardware is not supported by the spacer
unit.
When each module is installed, there should be approximately 1/32 of an inch vertical space between
adjacent modules. This can be achieved by ensuring that each module is installed at the center of
each standard rack increment. This space is important because it allows cards, fan, and power entry
modules to be removed without interference. Hardware is available in the installation kits for this
purpose. (See Figure7-5.)
Racks with one and two shelves are shown in Figure7-2. Racks with three and four shelves are
shown in Figure7-3.
The MGX 8220 shelf and cooling assembly rely on their contact with the rack for grounding.
Therefore, the rack should be properly connected to earth.
The equipment should be mounted in the rack to prevent any hazardous condition due to uneven
mechanical loading.