XRE200 Cooling System
The cooling system in an XRE200 External Routing Engine consists of two fan modules, left and right side air intake, and exhaust openings in the power supplies. The fan modules are located in the fan module slots on the back of the XRE200 External Routing Engine.
XRE200 External Routing Engines are shipped with fan modules installed in both fan module slots on the rear panel of the chassis (see Figure 1).
We recommend that you install both fan modules in an XRE200 External Routing Engine whenever possible. An XRE200 External Routing Engine can operate for a period of time with a single fan module; however, the chassis might shut down when the high temperature threshold is exceeded if a fan module is not available to properly cool the external Routing Engine.
Fan modules are hot-removable and hot-insertable field-replaceable units (FRUs).
Figure 2 shows the airflow in the XRE200 External Routing Engine.
Temperature sensors in the chassis monitor the temperature within the chassis. If the ambient temperature rises above the threshold 30°C, the speed of the working fans is automatically adjusted to keep the temperature within the acceptable range, 5°C through 40°C. The system raises an alarm if the fan fails or if the temperature inside the chassis rises above permitted temperature thresholds. The alarm temperature thresholds can be seen by entering the show chassis temperature-thresholds command.
If the ambient temperature inside the chassis rises above 75°C, the system shuts down automatically.
You can use the hardware chassis LEDs to monitor environmental status. See Chassis LEDs on an XRE200 External Routing Engine.