MX240 Ethernet Services Router Hardware Guide
RE might still be booting or the SCB is not receiving power. For more information, see “SCB Components” on page 13.
■RE
■Power supply
Troubleshooting the Cooling System
The router cooling system is a fan tray and an air filter, both of which are located vertically in the rear of the chassis (see Figure 1 on page 6). Figure 35 on page 82 shows the airflow through the router. To function properly, the entire cooling system requires an unobstructed airflow and proper clearance around the site, as described in “Preparing the Site for Router Installation” on page 29.
Figure 35: Airflow Through the Chassis
■An air filter installed in the rear of the chassis helps keep dust and other particles from entering the cooling system.
■The fan tray contains three fans. The fan tray provides cooling to the components installed in the router. During normal operation, the fans in the fan tray function at less than full speed. The SCB constantly monitors the temperatures detected by sensors and router components, adjusting the speed of the fans as necessary. The following conditions automatically cause the fans to run at full speed and also trigger the indicated alarm:
■A fan fails (red alarm).
■The fan tray is removed (yellow alarm and red alarm).
■The router temperature exceeds the “temperature warm” threshold (yellow alarm).
■The temperature of the router exceeds the maximum (“temperature hot”) threshold (red alarm and automatic shutdown of the power supplies).
To verify that the cooling system is functioning normally:
■Check the fan LEDs and alarm LEDs on the craft interface.
82■ Troubleshooting the Cooling System
