Chassis Cable Management; Chassis Cooling System; Cable Management Bracket - Cisco Carrier Routing System CRS-1 Installation Manual

Chapter 1 Overview

Chassis Cable Management

The Cisco CRS 4-slot line card chassis has cable management features for the front (PLIM) side of the
chassis, just above the card cage. The horizontal cable management trays have a special telescoping
feature that allows them to be extended when the chassis is upgraded with higher-density cards. This
extension also helps when installing the cables in the chassis.
Figure 1-5
Figure 1-5

Chassis Cooling System

The Cisco CRS 4-slot line card chassis has a single fan tray containing four fans that cool the chassis
card cage. Cool air flows in at the bottom front of the chassis and flows through the chassis card cage
and through the fans in the fan tray before being expelled through the top rear of the chassis (see
Figure
In addition, each power module at the bottom of the chassis has self-contained fans that pull in cool air
from the front of the chassis and exhaust warm air out the rear. Air also flows under the midplane,
through the SFCs, and then the fans to be expelled. There are these two parallel paths for air flow.
A replaceable air filter is located inside the chassis below the PLIM card cage at an angle. In addition,
there is a removable air filter on the front of the power tray air intake grille on the front (PLIM) side of
the chassis.
How often the air filters should be replaced depends on the facility environment. In a dirty environment,
or when you start getting frequent temperature alarms, you should always check the intake grille for
debris, and then check the air filters to see if they need to be replaced.
We recommend that you check the air filters once a month. Replace a filter when you notice a significant
Note
amount of dust.
OL-10971-10
shows the cable management bracket for the chassis.

Cable Management Bracket

1-6).
Cisco CRS Carrier Routing System 4-Slot Line Card Chassis Installation Guide
Chassis Cable Management
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