Cisco Explorer 4700, Hardware Installation And Maintenance Manual

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2-4 Cisco 4000 Series Hardware Installation and Maintenance
General Site Requirements
Site Configuration Precautions
The following precautions will help you plan an acceptable operating environment for your router
and will help you avoid environmentally caused equipment failures:
•
Remember that electrical equipment generates heat. Ambient air temperature might not be
adequate to cool equipment to acceptable operating temperatures without adequate circulation.
Ensure that the room in which your system operates has adequate circulation.
•
Never place chassis side by side because the heated exhaust air from one chassis can be drawn
into the intake port of the next.
•
Always follow the ESD-prevention procedures in the earlier section “Preventing Electrostatic
Discharge Damage” to avoid damage to equipment. Damage from static discharge can cause
immediate or intermittent equipment failure.
•
Ensure that the chassis cover and network processor module rear panels are secure. The chassis
is designed to allow cooling air to flow within. An open chassis allows air leaks, which may in
turn interrupt and redirect the flow of cooling air across internal components.
•
Check the power at your site to ensure that you are receiving “clean” power (free of spikes and
noise). Install a power conditioner if necessary.
•
Install proper grounding to avoid damage from lightning and power surges.
Equipment Racks
The following tips will help you plan an acceptable equipment rack configuration:
•
Enclosed racks must have adequate ventilation. Ensure that the rack is not overly congested
because each unit generates heat. An enclosed rack should have louvered sides and a fan to
provide cooling air.
•
When mounting a chassis in an open rack, ensure that the rack frame does not block the intake
or the exhaust ports. If the chassis is installed on slides, check the position of the chassis when it
is seated all the way into the rack.
•
In an enclosed rack with a ventilation fan in the top, excessive heat generated by equipment near
the bottom of the rack can be drawn upward and into the intake ports of the equipment above.
•
Baffles can help to isolate exhaust air from intake air, which also helps to draw cooling air
through the chassis. The best placement of the baffles depends on the airflow patterns in the rack,
which can be found by experimenting.
•
When equipment installed in a rack fails, particularly in an enclosed rack, try operating the
equipment by itself, if possible. Turn off other equipment in the rack (and in adjacent racks) to
allow the unit under test a maximum of cooling air and clean power.
Power Supply Features
Following are features of the router power supply:
•
Autoranging power supply (200W, 85 to 264 VAC or 40 to 72 VDC, 50 to 60 Hz)
•
6-foot electrical power cord