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EX9251 Cooling System
IN THIS SECTION
Airflow Direction in the EX9251 Switch Chassis | 21
Cooling System in the Power Supplies | 21
The cooling system components work together to keep all switch components within the acceptable
temperature range.
The cooling system in an EX9251 switch consists of three fan trays. Under normal operating conditions,
the fans in the fan trays run at a moderate speed. Temperature sensors inside the chassis monitor the
temperature of the switch components. If a fan fails or the ambient temperature rises above the
acceptable range, the system raises an alarm and the speed of the remaining fans is automatically
adjusted to keep the temperature within the acceptable range. If the ambient maximum temperature is
exceeded and the switch cannot be cooled adequately, the Routing Engine shuts down the switch.
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