Table Of Contents

Overview

Chassis Overview

Chassis Components

Chassis Slot Numbers

Chassis Cable Management

Chassis Cooling System

Chassis Power System

Safety Guidelines

Preventing Electrostatic Discharge

Overview

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This installation guide describes how to install the power, air circulation, line card, and external components into and remove them from a Cisco CRS-1 Carrier Routing System 8-Slot Line Card Chassis.

This chapter introduces the Cisco CRS-1 8-slot line card chassis at the highest level. It contains illustrations of the front and back of the chassis, complete with callouts to each hardware component. For details on each subsystem discussed in this chapter, see Cisco CRS-1 Carrier Routing System 8-Slot Line Card Chassis System Description.

This chapter presents the following topics:

•Chassis Overview

•Chassis Components

•Chassis Slot Numbers

•Chassis Cable Management

•Chassis Cooling System

•Chassis Power System

•Safety Guidelines

•Preventing Electrostatic Discharge

Chassis Overview

The Cisco CRS-1 8-slot line card chassis can be installed in locations where the 16-slot system may not fit (for example, colocation facilities, data centers, and many Tier II and Tier III locations). The routing system consists of a single rack-mount chassis that contains the following system components:

•Modular services cards (MSCs), also called line cards (up to eight)

•Physical layer interface modules, or PLIMs (up to eight, one for each MSC)

•Route processor (RP) cards (up to two)

•Switch fabric cards (SFCs) (up to four)

•A chassis midplane that connects MSCs to their associated PLIMs and to switch fabric cards

The Cisco CRS-1 8-slot line card chassis has its own power and cooling subsystems.

Chassis Components

This section lists the main components of a Cisco CRS-1 8-slot line card chassis. It primarily identifies the components that are considered field-replaceable units (FRUs), but where additional detail is useful identifies subassemblies that are not field replaceable.

Figure 1-1 and Figure 1-2 show the line card chassis from both the front (PLIM) and rear (MSC) sides.

Figure 1-1 Front (PLIM) View of Line Card Chassis

1	Cable management bracket	4	Air filter
2	Chassis vertical mounting brackets	5	Power modules
3	PLIM and RP slots (RPs in middle 2 slots)

Figure 1-2 Rear (MSC) View of Line Card Chassis

1	Upper fan tray (beneath cover)	4	MSC slots
2	Chassis vertical mounting brackets	5	Lower fan tray
3	Switch fabric card (half-height) slots	6	Power distribution units (PDUs)

The Cisco CRS-1 8-slot line card chassis contains:

•As many as eight modular services cards (MSCs, also called line cards) and eight physical layer interface modules (PLIMs). The MSC and PLIM are an associated pair of cards that mate through the chassis midplane. The MSC provides the forwarding engine for Layer 3 routing of user data, and the PLIM provides the physical interface and connectors for the user data.

The MSC can be associated with several different PLIMs, which provide different interface speeds and technologies. The available PLIMs are:

–1-port OC-768c/STM-256c packet-over-SONET (POS); available in short-reach (SR) optics.

–4-port OC-192c/STM-64c POS/DPT; available in long-reach (LR), intermediate-reach (IR), short-reach (SR), and very-short-reach (VSR) options.

–OC-48c/STM-16c POS/DPT, configurable with 1 to 16 ports; available in long-reach (LR) and short-reach (SR) options. This PLIM supports pluggable optics.

–10-Gigabit Ethernet (GE); available in long-reach (LR) optics. This PLIM supports pluggable optics, and can be configured with 1 to 8 ports.

–Cisco CRS-1 SPA Interface Processor-800. Occupies one physical-layer-interface-module (PLIM) slot on the Cisco CRS-1 16- and 8-Slot Line Card Chassis. Supports six normal-height SPAs or three double-height SPAs or any combination in between.

•A chassis midplane that connects MSCs to their associated PLIMs. The midplane design allows an MSC to be removed from the chassis without having to disconnect the cables that are attached to the associated PLIM. The midplane distributes power, connects the MSCs to the switch fabric cards, and provides control plane interconnections. The midplane is not field replaceable by the customer.

•One or two route processor cards (RPs). The RPs provide the intelligence of the system by functioning as the Cisco CRS-1 8-slot line card chassis system controller (serving as part of the control plane in multi-chassis systems) and providing route processing. Only one RP is required for system operation. For redundant operation, you can order a second RP as an option (CRS-8-RP/R). When two RPs are used, only one RP is active at a time. The second RP acts as a "standby" RP, serving as a backup if the active RP fails.

The RP also monitors system alarms and controls the system fans. LEDS on the front panel indicate active alarm conditions.

•Upper and lower fan trays. The fans pull cool air through the chassis. A removable air filter is located below the PLIM card cage at the front of the chassis.

•Four half-height switch fabric cards. These cards provide the three-stage Benes switch fabric for the routing system. The switch fabric performs the cross-connect function of the routing system, connecting every MSC (and its associated PLIM) with every other MSC (and its associated PLIM) in the system.

The switch fabric receives user data from one MSC and PLIM pair and performs the switching necessary to route the data to the appropriate egress MSC and PLIM pair. The switch fabric is divided into eight planes that are used to evenly distribute the traffic across the switch fabric. Each switch fabric card implements two planes of the switch fabric.

•A power system that provides redundant power to the chassis. The power system consists of two AC or DC power distribution units (PDUs) and two AC rectifier modules or two DC power entry modules (PEMs), one per PDU. Each PDU supplies input power to a rectifier or PEM, which in turn provides processed power to the chassis. Each DC and AC power module contains a removable air filter, located on the front of the module.

The PLIM side of the chassis is considered the front of the chassis, where user data cables attach to the PLIMs and cool air enters the chassis. The MSC side, which is where warm air is exhausted, is considered the rear of the chassis.

Chassis Slot Numbers

This section identifies the location and slot numbers for major cards and modules (primarily the field-replaceable units) that plug into the chassis.

Figure 1-3 shows the slot numbering on the front (PLIM) side of the Cisco CRS-1 8-slot line card chassis.

Figure 1-3 Line Card Chassis Slot Numbering—Front (PLIM) Side

As shown, the Cisco CRS-1 8-slot line card chassis numbers on the PLIM side of the chassis include the card cage with:

•Eight PLIM slots: left to right, 0, 1, 2, 3 ... 4, 5, 6, 7

•Two route processor card slots, RP0 and RP1.

Figure 1-4 shows the slot numbers on the rear (MSC) side of the Cisco CRS-1 8-slot line card chassis.

Figure 1-4 Line Card Chassis Slot Numbers—Rear (MSC) Side

As shown, the slot numbers on the MSC side of the chassis include:

•Fan tray

•Card cage, including:

–Eight line card slots (0, 1, 2, 3...4, 5, 6, 7)

–Four half-height switch fabric card slots (SM0, SM1, SM2, and SM3)

The MSC slot numbers are reversed from the PLIM slot numbers on the other side of the chassis. Because an MSC mates with its associated PLIM through the midplane, MSC slot 0 is on the far right side of the chassis looking at it from the rear (MSC) side.

PLIM slot 0 is on the far left side of the chassis, looking at if from the front (PLIM) side. MSC slot 0 and PLIM slot 0 mate with each other through the midplane, and so do all other MSC and PLIM slots (0 through 7).

Chassis Cable Management

The Cisco CRS-1 8-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.

The cable management bracket is shown in the following figure.

Figure 1-5 Cable Management Bracket

Chassis Cooling System

The chassis has two fan trays, each with several fans, that cool the chassis card cages. Cool air flows in at the bottom front of the chassis and flows through the chassis card cages and through the fans in the fan trays before being exhausted through the bottom rear of the chassis (see the following figure). In addition, each AC or DC 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.

A replaceable air filter is located on the front of the chassis below the PLIM card cage. Each power module also has a replaceable air filter that attaches to the module at 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 grills for debris, and then check the air filters to see if they need to be replaced.

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Note We recommend that you check the air filters once a month. Replace a filter when you notice a significant amount of dust.

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Figure 1-6 Airflow Through 8-Slot Line Card Chassis

The Cisco CRS-1 8-slot line card chassis airflow volumes are:

•Chassis airflow—Up to 900 cubic feet (25,485 liters) per minute

•Power system airflow—Up to 240 cubic feet (6,800 liters) per minute

Chassis Power System

The Cisco CRS-1 8-slot line card chassis is available with AC power distribution units (PDUs) that are configured for either AC Wye 3-phase, AC Delta 3-phase, or DC wiring. Each PDU has a different Cisco part number.

AC Wye and AC Delta PDUs basically both require 220 VAC input power:

•AC Wye 3-phase wiring is typically used in Europe and countries where each phase-to-neutral voltage is approximately 220 VAC; the nominal voltage for the power module is 230 V +/- 10%, which covers the 220 and 240 voltages that are present throughout Europe.

•AC Delta 3-phase wiring is typically used in the United States, Japan, and other countries where the phase-to-neutral voltage is approximately 120 VAC and approximately 208 VAC phase to phase.

For DC PDU, there is one type for both nominal -48 VDC and -50 VDC inputs.

Safety Guidelines

Before you perform any procedure in this document, review the safety guidelines in this section to avoid injuring yourself or damaging the equipment.

The following guidelines are for your safety and to protect equipment. The guidelines do not include all hazards. Be alert.

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Note Review the safety warnings listed in Regulatory Compliance and Safety Information that are applicable to your router before installing, configuring, or troubleshooting any installed card.

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•Keep the work area clear and dust-free during and after installation. Do not allow dirt or debris to enter into any laser-based components.

•Do not wear loose clothing, jewelry, or other items that could get caught in the router while working with MSCs, PLIMs, or their associated components.

•Cisco equipment operates safely when used in accordance with its specifications and product-usage instructions.

Preventing Electrostatic Discharge

Electrostatic discharge (ESD) damage, which can occur when electronic cards or components are improperly handled, results in complete or intermittent failures. We recommend to use an ESD-preventive strap whenever you handle network equipment or one of its components.

Following are guidelines for preventing ESD damage:

•Always use an ESD-preventive wrist or ankle strap and ensure that it makes good skin contact. Connect the equipment end of the connection cord to an ESD connection socket on the router or to a bare metal surface on the chassis.

•Handle a card by its ejector levers, when applicable, or the card's metal carrier only; avoid touching the board or connector pins.

•Place a removed card board-side-up on an antistatic surface or in a static-shielding bag. If you plan to return the component to the factory, immediately place it in a static-shielding bag.

•Avoid contact between the card and clothing. The wrist strap protects the board only from ESD voltage on the body; ESD voltage on clothing can still cause damage.