Cisco Systems Cisco 12008 manual Air Flow Guidelines

Site Requirements Guidelines

Air Flow Guidelines

The Cisco 12008 air circulation system includes two fan trays:

•Card cage fan tray—This router component is located behind the air filter assembly (see Figure 2-2).

The card cage fan tray draws ambient air through a removable and serviceable air filter assembly in the front of the router, passes it over the switch fabric cards in the lower card cage, directs it upward through the circuit boards in the upper card cage, and exhausts it through vents at the top rear of the router enclosure (see Figure 2-4).

•Power supply fan tray—This router component is located at the bottom of the power supply bay (see Figure 2-3).

The power supply fan tray draws ambient air through its faceplate, directs the air upward through the power supply bays, and exhausts it through vents at the top rear of the router enclosure (see Figure 2-4).

To ensure adequate air flow through the router’s internal components, it is recommend that you maintain a clearance of at least 6 inches (15.4 cm) in the front and back of the router enclosure at all times.

If airflow through the router is blocked or restricted, or if the ambient air being drawn into the router is too warm, an overtemperature condition within the router can occur. Under extreme conditions, the router’s environmental monitoring (MBus) system shuts down system power to protect internal electronic components from thermal damage.

The site should be as dust-free as possible. Dust tends to clog the air filter, reducing the flow of cooling air through the system and increasing the risk of an overtemperature condition.

2-10Cisco 12008 Gigabit Switch Router Installation and Configuration Guide