Power Connection Guidelines; Guidelines For Dc-Powered Systems; Guidelines For Ac-Powered Systems - Cisco ASR 903 Hardware Installation Manual

Installing the Power Supply
Use the information in the
requirements and heat dissipation of a Cisco ASR 903 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.

Power Connection Guidelines

This section provides guidelines for connecting the Cisco ASR 903 Router power supplies to the site
power source.
Warning Never defeat the ground conductor or operate the equipment in the absence of a suitably installed
ground conductor. Contact the appropriate electrical inspection authority or an electrician if you are
uncertain that suitable grounding is available. Statement 213
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:
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Guidelines for AC-Powered Systems

Basic guidelines for AC-powered systems include the following:
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Cisco ASR 903 Router Hardware Installation Guide
3-18
"DC Power Specifications" section on page 1-4
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.
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.
Chapter 3 Installing the Cisco ASR 903 Router
to estimate the power
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