Rack-Mounting And Air Flow Clearance Guidelines - Cisco ASR 9901 Manual

Preparing for Installation
Figure 8: Air Flow Path through the Cisco ASR 9001 Router
When selecting a site to install the router, observe these guidelines:
• Dust free area—Site should be as dust free as possible. Dusty environments can clog the power supply
• Unrestricted air flow—Allow sufficient air flow by maintaining a minimum of 6 inches (15.24 cm) of

Rack-Mounting and Air Flow Clearance Guidelines

The router can be mounted in most 2-post, 4-post, or telco-style 19-inch equipment racks that comply with
the Electronics Industries Association (EIA) standard for equipment racks (EIA-310-D). The rack must have
at least two posts with mounting flanges to mount the router chassis. The distance between the center lines
of the mounting holes on the two mounting posts must be 18.31 inches ± 0.06 inch (46.50 cm ± 0.15 cm).
The following figure shows examples of typical 2-post, 4-post, and telco-type equipment racks.
intake vents, reducing the cooling air flow through the router. Clogged filters and vents can cause an
over-temperature condition in the router.
clearance at both the inlet and exhaust openings on the chassis and the power modules. If the air flow is
blocked or restricted, or if the inlet air is too warm, an over-temperature condition can occur within the
router. Under extreme conditions, the environmental monitoring system powers off the router to protect
the components.
Rack-Mounting and Air Flow Clearance Guidelines
Preparing for Installation
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