APC AR4038A User Manual

This section provides information on how to install rack-mount equipment in the enclosure. The 
instructions provided with the equipment provide more detailed information.

When installing equipment, locate the top and bottom of a U-space on the mounting flanges. Every third 
hole on the mounting flanges of a NetShelter enclosure is numbered to indicate the middle of a U-space. 
A U-space consists of one of these numbered holes and one hole directly above and below it, as shown.

APC offers a cage nut hardware kit (AR8100) for use with square holes. Install cage nuts horizontally, 
with the ears engaging the sides of the square hole. Do NOT install cage nuts vertically with the ears 
engaging the top and bottom of the square hole.

1. Insert the cage nut into the square hole by hooking one ear of the cage nut assembly through the 

far side of the hole.

Note: Install the cage nuts on the interior of the vertical mounting flange.

2. Place the cage nut tool (not provided) on the other 

side of the cage nut and pull to snap it into position.

1. Remove any attached screw.
2. Grasp the cage nut and squeeze the sides to release 

it from the square hole.

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