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This chapter describes how to plan for the installation of the Cisco CRS 4-slot line card chassis (LCC).
![]() Note | The Cisco CRS Carrier Routing System 4-Slot Line Card Chassis Unpacking, Moving, and Securing Guide ships with your chassis and is the most up-to-date resource for unpacking and moving the chassis, and securing it to its operational location. |
The following sections are included:
This chapter describes how to plan for the installation of the Cisco CRS 4-slot line card chassis (LCC). The following sections are included:
![]() Note | The Cisco CRS Carrier Routing System 4-Slot Line Card Chassis Unpacking, Moving, and Securing Guide ships with your chassis and is the most up-to-date resource for unpacking and moving the chassis, and securing it to its operational location. |
The following tools are required to secure and install the Cisco CRS 4-slot LCC:
Before planning any aspect of the Cisco CRS 4-slot LCC installation, review the following general safety guidelines. This list is not inclusive of all potentially hazardous situations, so be alert.
The Cisco CRS 4-slot LCC is designed to meet regulatory, compliance, and safety approval requirements. If you require additional compliance information, see Cisco CRS Carrier Routing System Regulatory Compliance and Safety Information that is shipped with your chassis.
Electrostatic discharge (ESD) damage to chassis components can occur if the parts are handled improperly. Such mishandling can result in intermittent or complete failures of the equipment.
When handling any chassis components, observe the following guidelines to prevent ESD damage.
![]() Caution | Periodically check the resistance value of the antistatic ankle or wrist strap. The resistance measurement should be between 1 and 10 megohms. |
Physical Layer Interface Modules (PLIMs) are equipped with lasers, which emit invisible radiation. Do not stare into open PLIM ports.
Because invisible radiation may be emitted from the aperture of the port when no fiber cable is connected, avoid exposure to radiation and do not stare into open apertures. Statement 127
A fully configured Cisco CRS 4-slot LCC weighs approximately 361 lb. (163.7 kg). Before installing the chassis, ensure that your site is properly prepared so you can avoid having to move the chassis later to accommodate power source and network connections.
Each time you lift any heavy assembly, refer to these lifting guidelines:
The field replaceable units (FRUs) in the Cisco CRS 4-slot LCC offer online insertion and removal (OIR) capability, which means an FRU is hot swappable and can be removed and replaced while the system is operating without presenting an electrical hazard or damage to the system.
The following FRUs feature OIR:
![]() Note | For more information on installing and removing components, see the Cisco CRS Carrier Routing System 4-Slot Line Card Chassis Installation Guide. |
Working with electrical equipment can be hazardous. Three types of potential hazards are addressed in this section.
Use these guidelines if an electrical accident occurs while working with any electrical equipment.
Before assisting an injured person, make sure there is no possibility of electrical shock or other potential hazard to yourself.
Use these guidelines when working with equipment you want to install:
Use these guidelines when working with equipment that is disconnected from a power source, but is still connected to telephone or network wiring.
Space planning for the Cisco CRS 4-slot LCC is consistent with other chassis that install in a standard 19-inch (48-cm) Telco equipment rack. This section includes the following topics:
Before installing the Cisco CRS 4-slot LCC in a rack, consider the following general rack-mounting guidelines.
![]() Note | Warm air exhausts at the back of the chassis through the fan tray. Allow sufficient air flow by maintaining a minimum of 6 inches (15 cm) of clearance at the front and rear of the chassis. |
![]() Note | The rack-mounting hardware included with the Cisco CRS 4-slot LCC is suitable for most 19-inch (48-cm) equipment racks. |
One of the unique features of the Cisco CRS 4-slot LCC is its size. Up to two chassis can fit in a standard 19-inch (48-cm) equipment rack. When placing multiple chassis in a rack, ensure there is sufficient ventilation to accommodate both chassis.
Hot exhaust air from other equipment can enter the inlet air vents and cause an overtemperature condition inside the chassis.
The figure below shows a top view of the Cisco CRS 4-slot LCC footprint. The front of the chassis is at the top of the figure.
1 |
Depth (without cosmetic doors) 30.2 in. (76.9 cm) |
2 |
Width 18.5 in. (47.1 cm) |
Make sure that enough space exists at the installation site to install the line card chassis and allow sufficient airflow. The floor plan must also provide enough room to access chassis components for maintenance (for example, to remove fan trays, power supplies, cables, and the air filter). The figure below shows a typical floor plan and the table below lists the minimum clearances required.
The table below lists the minimum installation and maintenance access clearances required for the chassis.
Type of Access |
Clearance Required |
Purpose |
---|---|---|
Chassis Clearance |
||
Front |
36 in. (91.4 cm) |
To allow access to chassis components (for example, to access cables). |
Rear |
24 in. (61 cm) |
To allow access to chassis components (for example, to remove fan trays, power supplies, and air filters). |
Inlet and exhaust openings (chassis and power supplies) |
6 in. (15.2 cm) |
To allow sufficient airflow for chassis components. |
Side of chassis (left and right) |
None |
|
Aisle Clearance |
||
Aisle width |
50 in. (127 cm) |
To move the chassis through an aisle. |
|
||
Turn radius of chassis |
50 inches (127 cm) |
To turn the chassis. |
![]() Note | The most up-to-date clearance requirement information is located in the Cisco CRS Carrier Routing System 4-Slot Line Card Chassis Unpacking, Moving, and Securing Guide. |
![]() Note | For front-to-front row alignment and back-to-back row alignment: we recommend that adjacent rows of chassis align the front intake to front intake or rear exhaust to rear exhaust. |
The chassis power system provides power to chassis components and is made up an AC or DC power shelf that contains four power supplies. Each power supply is connected to a separate and independent power source.
Each power supply receives input power from a different power source. The power system provides 1+1 redundancy. During normal operation, the power shelf and power supplies function together to power the chassis. However, if a power source to one or two power supplies fails, the remaining power supplies provide enough input power to power the chassis. This 1+1 redundancy enables the chassis to operate despite a limited power failure or during power supply replacement.
The Cisco CRS 4-slot LCC features a single power shelf consisting of four 2000-W AC or DC power supplies. Site requirements differ depending on the type of power source voltage.
This section includes the following topics:
![]() Note | For additional power system details, see the Cisco CRS Carrier Routing System 4-Slot Line Card Chassis Installation Guide. |
This section describes the power and grounding requirements you must consider when planning the site facilities for the line card chassis. In addition, see the AC Power System and the DC Power System for additional power requirements.
![]() Note | A certified electrician should review the information in these sections to ensure that the installation site meets these requirements. For larger system configurations, you may want to consult a facilities electrical expert to understand the load that the routing system may put on the facility power plant. |
![]() Note | Be sure to review the safety warnings in Cisco CRS Carrier Routing System Regulatory Compliance and Safety Information. |
This section offers site wiring guidelines for setting up the plant wiring and cabling at your site. When planning the location of the new system, consider the following:
Electromagnetic interference can occur between the signal on the wires and external or ambient EMI fields when the wires are run for any significant distance. Bad wiring practice can result in radio interference emanating from the plant wiring.
![]() Note | To predict and remedy strong EMI, you may need to consult experts in radio frequency interference (RFI). |
If you use twisted-pair cable in your plant wiring with a good distribution of grounding conductors, the plant wiring is unlikely to emit radio interference. If you exceed the recommended distances, use a high-quality twisted-pair cable with one ground conductor for each data signal when applicable.
Give special consideration to the effect of a lightning strike in your vicinity if wires exceed recommended distances, or if wires pass between buildings. The electromagnetic pulse (EMP) caused by lightning or other high-energy phenomena can easily couple enough energy into unshielded conductors to destroy electronic devices.
Provide a properly grounded and shielded environment, with special attention to issues of electrical surge suppression, to avoid the time loss to identify and resolve future surge and distance issues after your chassis is installed.
Each AC-powered line card chassis requires 4270 watts (4.27 kW) of AC input power. Two of the four 2000-watt power supplies must be functioning in order to properly power the chassis. The power supplies are 92percent efficient.
Each AC-powered chassis includes a single power shelf consisting of four power supplies. This “two and two” configuration within the single power shelf provides 1+1 redundancy. Each power supply requires one input power connection. The power shelf supports four AC-to-DC power supplies that are FRUs. The AC-to-DC power supplies convert 200 to 240 VAC power to –54 VDC used by the Cisco CRS 4-slot LCC.
The power cables, which are 13 feet (4 m) long, are not shipped preattached to the power shelf. The figure below shows the AC power cord plug. AC power input is 2 wires + protective earthing. The gauge of the earth conductor must be equal to or larger than that of the phase conductor.
For additional power system details, see the Cisco CRS Carrier Routing System Line Card Chassis Installation Guide.
The Cisco CRS 4-slot LCC DC power shelf consists of two major components (see the figure below):
When installing the DC power shelf, these two components are mated to create the complete DC power shelf.
The figure below shows the PIM and the DC power input shelf.
1 |
DC power input shelf |
2 |
Power input module (PIM) |
The Cisco CRS 4-slot LCC DC power system provides 4,000 watts to power the chassis. (To provide power redundancy, up to 8,000 watts are available.) Each DC-powered chassis contains four DC power supplies for 2N redundancy. The PIM provides the input power connections. Note that each power connection has two cables: –48 VDC and return. The PIM, DC power input shelf, and the power supplies are field replaceable.
The Cisco CRS 4-slot LCC requires a total of four dedicated pairs of 60-A DC input power connections, one pair for each of the power supplies, to provide redundant DC power to the Cisco CRS 4-slot LCC midplane.
For full 2N redundancy, we recommend that you have two independent –48 VDC power sources to provide power to the Cisco CRS 4-slot LCC. Connect the two 60-A DC inputs on the left to one wiring block, and the two 60-A DC inputs on the right to the other wiring block.
For more information, see Chapter 2, “Installing and Removing Power Components,” in the Cisco CRS Carrier Routing System Line Card Chassis Installation Guide .
Proper air circulation and cooling are essential to ensure optimal Cisco CRS 4-slot LCC operation. This section includes information on how to plan for the environment that the chassis will be operated in. This section includes the following topics:
This section offers guidelines for operating your Cisco CRS 4-slot LCC in various environments. Included are airflow, temperature, and humidity recommendations. To assure normal operation and avoid maintenance difficulty, plan and prepare your site before you install the chassis.
The airflow through the Cisco CRS 4-slot LCC is controlled by a push-pull configuration. The figure below shows how ambient air flows in at the bottom front of the Cisco CRS 4-slot LCC and up through the card cages until it exhausts at the top rear. The power supplies in the power shelves have their own self-contained cooling fans. The Cisco CRS 4-slot LCC has a maximum airflow of 880 cubic feet (24,918 liters) per minute.
A replaceable air filter is positioned above the power shelf. How often the air filter 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 filter to see if it needs replacement.
![]() Caution | Do not remove the air filter with the fan tray functioning. See the Cisco CRS Carrier Routing System 4-Slot Line Card Chassis Installation Guide for specific instructions on how to service the air filter. |
As shown in the above figure, air circulates through the card cage, and exhausts at the back of the chassis
Under extreme environment conditions, the environmental monitoring system shuts down the power to protect the system components.
The operating environmental site requirements are listed in Cisco CRS 4-Slot Line Card Chassis System Specifications of the Cisco CRS Carrier Routing System 4-Slot Line Card Chassis Site Planning Guide The temperature and humidity ranges listed are those within which the chassis continues to operate. You can maintain normal operation by anticipating and correcting environmental irregularities before they approach critical values.
The environmental monitoring functionality built into the chassis protects the system and components from potential damage from overvoltage and overtemperature conditions.
Cabling runs should be carefully planned. The basic configurations for various routing systems should be arranged to minimize the complexity and length of the cable runs. Precut and terminated cables are considered part of the basic configuration. This section includes the following topics:
You must provide the MSC and PLIM interface cables. You also provide the cable management trays for these cables from the Cisco CRS 4-slot LCC to your facility interconnect. Interfaces vary with each system site, plan these data cable runs in advance of the system installation.
The Cisco CRS 4-slot LCC has cable-management features for the front of the chassis. These cable-management features consist of horizontal cable-management trays above the card cage. These trays have a special telescoping feature that allows them to be extended when the chassis is upgraded with higher-density cards. This extension feature also helps in installing the cables in the chassis.
For detailed information about chassis cabling and cable management, see the Cisco CRS Carrier Routing System 4-Slot Line Card Chassis Installation Guide.
The following is a list of tasks you can consider doing to configure the line card chassis for high availability, which helps to ensure that service is not disrupted due to failures:
To provide more high availability, you can also install each line card chassis in a different room, located in a different fire and power zone. This way, a problem in one room should not affect the operation of the other chassis.