Understanding Redundant Cooling System Components ! 537
Chapter 39: Monitoring Redundant Cooling System Components
T640 Routing Node Redundant Cooling System Components
The T640 routing node cooling system includes:
! Two front fan trays
! Front air filter
! Rear fan tray
! Rear air filter
The cooling system components work together to keep all router components
within the acceptable temperature range (see Figure 223). All fan trays and filters
are hot-insertable and hot-removable. The two front fan trays are interchangeable.
The front and rear fan trays are not interchangeable.
Figure 223: T640 Routing Node Cooling System and Airflow
The cooling system has redundant components, which are controlled by the host
subsystem. If one of the fans fails, the host subsystem increases the speed of the
remaining fans to provide sufficient cooling for the router indefinitely.
The host subsystem monitors the temperature of the router components. When the
router is operating normally, the fans function at lower than full speed. If a fan fails,
the speed of the remaining fans is automatically adjusted to keep the temperature
within the acceptable range. Cooling system components can be removed and
replaced without powering down or disconnecting power to the router. Figure 224
on page 538 shows the T640 routing node cooling system components.
Side view
Front view
1504
Rear
Rear view
Air intake
Left
Right
Air exhaust
Card cage
Air intake cover
Air flow (front boards) Air flow (front boards)Air flow (back boards)
Fan tray
Fan tray
Front
Card cage
To Next Page
Need help?
General
