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Cisco ONS 15454 Installation and Operations Guide
November 2001
Chapter1 Hardware Installation
Rack Installation

Procedure: Mount the Shelf Assembly in a Rack (Two People)

Step 1 Ensure that the shelf assembly is set for the desired ra ck size (eith er 19 o r 23 inch es) .
Step 2 Lift the shelf assembly to the desired position in the rack.
Step 3 Align the screw holes on the mounting ears with the mounting holes in the rack.
Step 4 While one person holds the shelf assembly in place, the other person c an install one mounting screw in
each side of the assembly.
Step 5 When the shelf assembly is secured to the rack, install the remaining mounting screws.
Note Use at least one set of the horizontal screw slots on the ONS 15454 to prevent future slippage.
1.3.3 Mounting Multiple Nodes
Most standard seven-foot racks can hold four ONS 15454s and a fuse and alarm panel. However, unequal
flange racks are limited to three ONS 15454s and a fuse and alarm panel or four ONS 15 454s and a fu se
and alarm panel from an adjacent rack.
If you are using the bottom brackets to install the fan-tray air filter, you can instal l three shelf assemblies
in a standard seven-foot rack. If you are not using the bott om b ra ckets , yo u c an inst all four sh elf
assemblies in a rack. The advantage to using the bottom brackets is that you ca n replace the filter without
removing the fan tray.

Procedure: Mount Multiple Shelf Assemblies in a Rack

Note The ONS 15454 must have one inch of airspace below the i nstalled shelf assembly to allow air flow
to the fan intake. If a second ONS 15454 is installed undernea th a shelf assembly, the air ramp on top
of the bottom shelf assembly provides the desired space. However, if the ONS 15454 is installed
above third-party equipment, you must provide a minimum spacing of one inch between the
third-party shelf assembly and the bottom of the ONS 15454. The third-party equipment must not
vent heat upward into the ONS 15454.
Step 1 Install the fuse and alarm panel in the top space.
Step 2 Mount the first ONS 15454 directly below the fuse and ala rm p ane l.
Step 3 Repeat the procedure with the third and fourth ONS 15454s.

1.3.3.1 Four Node Configuration

You can link multiple ONS 15454s using their OC-N cards (i.e., create a f iber-optic bus) to accommodate
more access traffic than a single ONS 15454 can support. For exa m ple, if yo u n eed to dro p m or e th an
112 DS-1s or 96 DS-3s (the maximum that can be aggregated in a single n ode ), yo u c an l ink t he no de s