Cisco Systems 15454 1.15 Power and Ground Description

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Cisco ONS 15454 Reference Manual, R7.0

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Chapter 1 Shelf and Backplane Hardware

1.15 1.14.3 Air Filter

The ONS 15454 contains a reusable air filter; Model 15454-FTF2, that is installed either beneath the

fan-tray assembly or in the optional external filter brackets. Earlier versions of the ONS 15454 used a

disposable air filter that is installed beneath the fan-tray assembly only. However, the reusable air filter

is backward compatible.

The reusable filter is made of a gray, open-cell, polyurethane foam that is specially coated to provide fire

and fungi resistance. All versions of the ONS 15454 can use the reusable air filter. Spare filters should

be kept in stock.

Caution Do not operate an ONS 15454 without the mandatory fan-tray air filter.

Caution Inspect the air filter every 30 days, and clean the filter every three to six months. Replace the air filter

every two to three years. Avoid cleaning the air filter with harsh cleaning agents or solvents. Refer to the

Cisco ONS 15454 Troubleshooting Guide for information about cleaning and maintaining the fan-tray

air filter.

1.15 Power and Ground Description

Ground the equipment according to Telcordia standards or local practices.

Cisco recommends the following wiring conventions, but customer conventions prevail:

• Red wire for battery connections (–48 VDC)

• Black wire for battery return connections (0 VDC)

• The battery return connection is treated as DC-I, as defined in GR-1089-CORE, issue 3.

The ONS 15454 has redundant –48 VDC #8 power terminals on the shelf-assembly backplane. The

terminals are labeled BAT1, RET1, BAT2, and RET2 and are located on the lower section of the

backplane behind a clear plastic cover.

To install redundant power feeds, use four power cables and one ground cable. For a single power feed,

only two power cables (#10 AWG, 2.588 mm² [0.1018 inch], copper conductor, 194°F [90°C]) and one

ground cable (#6 AWG, 4.115 mm² [0.162 inch]) are required. Use a conductor with low impedance to

ensure circuit overcurrent protection. However, the conductor must have the capability to safely conduct

any faulty current that might be imposed.

The existing ground post is a #10-32 bolt. The nut provided for a field connection is also a #10 AWG

(2.588 mm² [0.1018 inch]), with an integral lock washer. The lug must be a dual-hole type and rated to

accept the #6 AWG (4.115 mm² [0.162 inch]) cable. Two posts are provided on the Cisco ONS 15454 to

accommodate the dual-hole lug. Figure 1-41 shows the location of the ground posts.