EX4200 Cooling System
The cooling system in an EX4200 switch consists of a field-replaceable unit (FRU) fan tray with three fans (see Figure 1). All the EX4200 switch models, except the EX4200-24F-S and EX4200-48T-S switches are shipped with one fan tray pre-installed in the rear panel of the switches. EX4200-24F-S and EX4200-48T-S switches are not shipped with pre-installed fan tray; you must order them separately.
The fan tray is located at the rear of the chassis.
Airflow Direction in the EX4200 Switch Chassis
The fan tray located at the rear of the chassis provides side-to-rear chassis cooling (see Figure 2).
The fan tray used in an EX4200 switch comes with load-sharing redundancy that can tolerate a single fan failure at room temperature (below 45° C/113° F) to still provide sufficient cooling.
Temperature sensors in the chassis monitor the temperature within the chassis. The system raises an alarm if the fan fails or if the temperature inside the chassis rises above permitted levels. If the temperature inside the chassis rises above the threshold, the system shuts down automatically and the temperature shutdown LED on the rear panel is lit. You can see the status of fans and the temperature from the Show Environment Status option in the Status menu in the LCD panel.