Cisco ASR 5500, Руководство по установке

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C H A P T E R
12
Replaceable Components
This chapter describes how to remove and replace the following components:
• Air Filters, page 121
• Fan Tray Units, page 127
• PFU, page 135
• Circuit Cards, page 137
• Returning Failed Components, page 147
Air Filters
Lower fan trays draw ambient air into the chassis. Each is equipped with a particulate air filter to prevent dust
and debris from entering the chassis. The two air filters (one front and one rear) must be changed periodically
to ensure proper ventilation and air flow through the chassis.
You should replace the air filters at least every six months. Keep replacement air filters on site. A single kit
includes filters for both the front fan tray and the rear fan tray (ASR55-FLTR-AIR-F=). Having this kit on-hand
ensures that qualified service personnel can quickly replace the filters as necessary. The filters should be
replaced during a maintenance window when low traffic volume is expected.
Determining When an Air Filter Needs Replacing
If the air filters are replaced at least every six months as part of routine maintenance, there should be no need
for out-of-cycle replacement. However, under certain conditions, the air filters may need replacement between
maintenance periods.
High Operating Temperatures and Fan Speeds
One possible indication that air filters need to be replaced is if the chassis temperature remains high for
extended periods of time. This condition causes the multi-speed fans to run at high speed. Clogged and dirty
air filters could hinder air flow through the chassis and result in higher operating temperatures.
ASR 5500 Installation Guide
121