Cisco ASR-920-24TZ-M Installation Guide

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Cisco ASR-920-24SZ-IM, ASR-920-24SZ-M, ASR-920-24TZ-M Aggregation Services Router Hardware Installation Guide
Chapter 3 Installing
Installing the Chassis Ground Connection
Warning The plug-socket combination must be accessible at all times because it serves as the main
disconnecting device. Statement 1019
Warning This product requires short-circuit (overcurrent) protection, to be provided as part of the building
installation. Install only in accordance with national and local wiring regulations. Statement 1045
Guidelines for DC-Powered Systems
Basic guidelines for DC-powered systems include the following:
• Each chassis power supply should have its own dedicated input power source. The source must
comply with the safety extra-low voltage (SELV) requirements in the UL 60950, CSA 60950, EN
60950, and IEC 60950 standards.
• The circuit must be protected by a dedicated two-pole circuit breaker. The circuit breaker should be
sized according to the power supply input rating and local or national code requirements.
• The circuit breaker is considered the disconnect device and should be easily accessible.
• The system ground is the power supply and chassis ground.
• Do not connect the DC return wire to the system frame or to the system-grounding equipment.
• Use the grounding lug to attach a wrist strap for ESD protection during servicing.
• Ensure the DC return is grounded at the source side.
Guidelines for AC-Powered Systems
Basic guidelines for AC-powered systems include the following:
• Each chassis power supply should have its own dedicated branch circuit.
• The circuit breaker should be sized according to the power supply input rating and local or national
code requirements.
• The AC power receptacles used to plug in the chassis must be the grounding type. The grounding
conductors that connect to the receptacles should connect to protective earth ground at the service
equipment.
Preventing Power Loss
Use the following guidelines to prevent power loss to the router:
• To prevent loss of input power, ensure that the total maximum load on each circuit supplying the
power supplies is within the current ratings of the wiring and breakers.
• In some systems, you can use an UPS to protect against power failures at your site. Avoid UPS types
that use ferroresonant technology. These UPS types can become unstable with systems such as the
Cisco ASR 920 Series Router, which can have substantial current-draw fluctuations due to bursty
data traffic patterns.
Use the information in the Table 1-3 to estimate the power requirements and heat dissipation of a
Cisco ASR 920 Series Router based on a given configuration of the router. Determining power
requirements is useful for planning the power distribution system needed to support the router.

Cisco ASR-920-24TZ-M Specifications

General

Brand	Cisco
Model	ASR-920-24TZ-M
Category	Network Router
Language	English