If you are mounting the chassis in a 4-post enclosed cabinet, ensure that you have a minimum of 6 inches
(15.24 cm) of clearance on each side of the chassis.
Floor Loading Considerations
Ensure that the floor under the rack supporting the Cisco ASR 903 Routers is capable of supporting the
combined weight of the rack and all the other installed equipment.
To assess the weight of a fully configured Cisco ASR 903 Router, refer to
Cisco ASR 900 Series Aggregation
For additional information about floor loading requirements, consult
GR-63-CORE, Network Equipment
Building System (NEBS) Requirements: Physical Protection
.
Site Power Guidelines
The Cisco ASR 903 Router has specific power and electrical wiring requirements. Adhering to these
requirements ensures reliable operation of the system. Follow these precautions and recommendations when
planning your site power for the Cisco ASR 903 Router:
• The redundant power option provides a second, identical power supply to ensure that power to the chassis
continues uninterrupted if one power supply fails or input power on one line fails.
• In systems configured with the redundant power option, connect each of the two power supplies to
separate independent power source. If you fail to do this, your system might be susceptible to total power
failure due to a fault in the external wiring or a tripped circuit breaker.
• To prevent a loss of input power, be sure that the total maximum load on each circuit supplying the power
supplies is within the current ratings of the wiring and the breakers.
• Check the power at your site before installation and periodically after installation to ensure that you are
receiving clean power. Install a power conditioner if necessary.
• Provide proper grounding to avoid personal injury and damage to the equipment due to lightning striking
power lines or due to power surges. The chassis ground must be attached to a central office or other
interior ground system.
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.
Caution
The Cisco ASR 903 Router installation must comply with all the applicable codes and is approved for use
with copper conductors only. The ground bond fastening hardware should be of compatible material and
preclude loosening, deterioration, and electrochemical corrosion of hardware and joined material. Attachment
of the chassis ground to a central office or other interior ground system must be made with a 6 AWG gauge
wire, copper ground conductor at a minimum.
Note
The maximum power draw of the Cisco ASR 903 Router chassis and its configurable hardware components
are listed in the following table. The maximum power draw values are not affected by whether the router
chassis contains 1 or 2 power supplies AC or DC.
Cisco ASR 903 and ASR 903U Aggregation Services Router Hardware Installation Guide
60
Preparing for Installation
Floor Loading Considerations