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Cisco ONS 15454 Reference Manual, R8.5.x
78-18106-01
Chapter 1 Shelf and Backplane Hardware
1.2.3 Mounting Multiple Nodes

1.2.3 Mounting Multiple Nodes

Most standard (Telcordia GR-63-CORE, 19-inch [482.6 mm] or 23-inch [584.2 mm]) seven-foot
(2,133 mm) racks can hold four ONS 15454 shelves and a fuse and alarm panel. However, unequal flange
racks are limited to three ONS 15454 shelves and a fuse and alarm panel or four ONS 15454 shelves and
a fuse and alarm panel from an adjacent rack.
If you are using the external (bottom) brackets to install the fan-tray air filter, you can install three shelf
assemblies in a standard seven-foot (2.133 m) rack. If you are not u sing the external (bottom) brackets,
you can install four shelf assemblies in a rack. The advantage to using the bottom brackets is that you
can replace the filter without removing the fan tray.

1.2.4 ONS 15454 Bay Assembly

The Cisco ONS 15454 bay assembly simplifies ordering and installing the ONS 15454 because it allows
you to order shelf assemblies preinstalled in a seven-foot (2.133 m) rack. The bay a ssembly is available
in a three- or four-shelf configuration. The three-shelf configuratio n includes three ONS 15454 shelf
assemblies, a prewired fuse and alarm panel, and two cable-management trays. The four-shelf
configuration includes four ONS 15454 shelf assemblies and a prewired fuse and alarm pa nel. You can
order optional fiber channels with either configuration. Installation procedur es are included in the
Unpacking and Installing the Cisco ONS 15454 Four-Shelf and Zero-Shelf Bay Assembly document that
ships with the Bay Assembly,
1.3 Front Door
The Critical, Major, and Minor alarm LEDs visible through the front door indicate whether a critical,
major, or minor alarm is present anywhere on the ONS 15454. Th ese LEDs must be visible so
technicians can quickly determine if any alarms are present on the ONS 15454 shelf or the network. You
can use the LCD to further isolate alarms. The front door (Figure 1-3) provides access to the shelf
assembly, cable-management tray, fan-tray assembly, and LCD screen.