Preventing Power Loss; Power Connection Guidelines; Guidelines For Dc-Powered Systems; Guidelines For Ac-Powered Systems - Cisco ASR-920-24SZ-IM Installation Manual

Installing the Power Supply

Preventing Power Loss

Use the following guidelines to prevent power loss to the router:
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Power Connection Guidelines

This section provides guidelines for connecting the Cisco ASR 920-24SZ-IM, ASR-920-24SZ-M,
ASR-920-24TZ-M Router power supplies to the site power source.
This equipment is intended to be grounded to comply with emission and immunity requirements.
Warning
Ensure that the switch functional ground lug is connected to earth ground during normal use.
Statement 1064
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-920-24SZ-IM, ASR-920-24SZ-M, ASR-920-24TZ-M Aggregation Services Router Hardware Installation Guide
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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 920-24SZ-IM, ASR-920-24SZ-M, ASR-920-24TZ-M Router, which can have
substantial current-draw fluctuations due to bursty data traffic patterns.
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.
Chapter 3 Installing