Power Supply Features - Cisco ASR 903 Quick Start Manual

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Power Supply Features

The Cisco ASR 903 Router support AC and DC power supplies. For more information about installing the Cisco ASR 903 Router
power supplies, see the Installing the Power
To estimate the required power supply, use the
The power sections provide more information about the power supply:
Redundancy
The Cisco ASR 903 Router chassis includes a slot for an optional redundant power supply. The redundant power supply option
provides a second power supply to ensure that power to the chassis continues uninterrupted if one power supply fails or input power
on one line fails. Redundancy is supported either with identical power supplies or a combination of AC and DC power supply. The
Cisco ASR 903 Router supports current sharing between the power supplies.
A redundant power supply on the Cisco ASR 903 Router is recommended. Each power supply should be connected to separate
independent power sources to ensure that the router maintains power in the event of a power interruption caused by an electrical
failure, a wiring fault, or a tripped circuit breaker.
To comply with IEC 61850-3 (voltage interruptions), redundant power supplies with separately derived
Caution
power feeds are required.
Dying Gasp
The Cisco ASR 903 Router DC power supply supports the Dying Gasp feature, which allows the router to provide an input power
loss notification to the RSP so that the RSP can send appropriate SNMP traps or OAM messages and update log files on the router.
With the DC power supply, the router supports a minimum input power loss detection time of 2 milliseconds (DC) and continued
operation of at least 6 milliseconds (DC) after the notification.
Continued DC power supply operation may vary for voltages other than +24/-48V.
Note
Dying Gasp is not supported on the ASR 900 RSP3 module for 1200W DC power supply.
Note
Status LEDs
LEDs are also provided on each power supply to indicate the status of the input power and the health of the power supply. For more
information about the LEDs on the Cisco ASR 903 Router, see the Troubleshoting section in the Cisco ASR 903 and ASR 903U
Aggregation Services Router Hardware Installation Guide.
Fan tray
Redundant power units (two DC power units are shown)
Supply.
Cisco Power Calculator.
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