CoolingSystem and Airflow in an EX8208 Switch
Thecooling system in an EX8208 switch consists of a singlefan tray. The fan tray is a
hot-insertableand hot-removable field-replaceableunit (FRU). The fan tray contains12
fans.
Thefan tray installs verticallyon the left side on the front of the chassis and provides
side-to-sidechassis cooling. A handle on the front faceplatefacilitates handling of the
fantray. See Figure30 on page 53.

Figure30: Fan Tray for an EX8208 Switch

Thefan tray can be removed and replacedfrom the front of the chassis. The switch
continuesto operate for a limited time (2minutes) during the replacement of the fan
traywithout thermal shutdown.
CAUTION: Youmust replacethe fan tray within 2 minutes of removing it.
Theair intake to cool the chassis is locatedon the right side of the chassis. Air is pulled
intothe chassis and is pushed thorough the line card cage towardsthe fan tray. Hot air
exhaustsfrom the left side of the chassis. See Figure 31 on page54.
53Copyright© 2010, Juniper Networks,Inc.
Chapter2: Component Descriptions