T640 Router Three-Input 240-A DC Power Supply Load Sharing and Fault Tolerance
When the router is operating normally and both power supplies are switched on, load sharing between them occurs automatically. When one power supply fails or is turned off, the other power supply immediately assumes the entire electrical load for the system. A single power supply can provide full power for as long as the router is operational. Table 1 describes the behavior of the power supply if one of the inputs fails.
Table 1: Fault Tolerance
| Redundancy | Fault Tolerance When One Input Fails or is Disconnected |
|---|---|
Nonredundant power supply | If this input fails, the router shuts down. Note: We recommend that you install redundant power supplies. |
Redundant power supplies | If an input on one power supply fails, the other power supply assumes the electrical load for all inputs. If one input on the other power supply is not functional, the router shuts down. |
