Specifications

Installation and Start-up 7-11
Rack Mounting the MGX 8220 Units
Figure7-5 Keyhole Style Bracket
Rack Mounting the Plenum or Spacer
Either the plenum chamber or the spacer unit (not both) should be mounted immediately above the
shelf. The decision of which one to use is dependent upon the configuration of equipment in the rack
and how the air is to be expelled. The plenum delivers air to the rear of the rack and is used in normal
UL compliant installations where the top of the unit must be covered. The spacer may be used for
installations that may have equipment mounted above the MGX 8220 assembly that acts as the
necessary top cover. The spacer guarantees the minimum necessary air exhaust space of 1.75 inches
providing the sides and rear are open and unobstructed. The MGX 8220 shelf may not be UL
compliant when the spacer is used. Further, the plenum supports the attachment of a cable
management kit whereas the spacer does not. This is an important factor if cable management is to
be used for the upper shelf in two and four shelf configurations.
Insert the selected unit immediately above the shelf and secure to the shelf with four, number 10-32
machine screws and flat washers.
Mounting the Electrostatic Wrist Strap
The MGX 8220 shelf is provided with a wrist strap which grounds the user and protects the
electronic components from electrostatic shock. The wrist strap kit consists of a strap, a coiled cord,
and a clip for holding the strap as shown in Figure7-6.
It is recommended that the wrist strap be installed on the left front flange of one of the units at a
convenient height. Use the front mounting screw to secure the ring lug to the flange and front rail.
The other end of the cord is attached to the strap with a snap connector. Peel the back off the clip to
expose the adhesive surface and attach to the front of the unit above the ring lug. Mount the clip
sideways to allow the strap to be held in a position that will not interfere with the removal of the
number1 card. Use the clip to store the strap when not in use. (See Figure 6-7.)