3Com 4007, Implementation Manual, Page: 115 / 684

Load-Sharing Power Supplies 115
If a power supply fails while the chassis is running in fault-tolerant mode:
■
The EME automatically disables fault-tolerant mode.
■
Power formerly reserved is made available by power class and slot
location to power-enabled modules to prevent them from powering
off (as an attempt to bring power consumption under the
now-reduced power budget).
■
All modules that had power before the power supply failure continue
to receive power without interruption.
■
Upon power supply recovery (or replacement), the EME automatically
reenables fault-tolerant mode.
Setting Power
Fault-Tolerance
By default, the chassis is set to non-fault-tolerant mode. To set the chassis
to power fault-tolerant mode or to power non-fault-tolerant mode, enter
set power mode
at the EME prompt.
Use the following syntax:
set power mode fault_tolerant
set power mode non_fault_tolerant
The following example sets the power mode to fault-tolerant:
CB9000> set power mode fault_tolerant
Power will switch to FAULT_TOLERANT mode when sufficient
power is available
When you attempt to set the chassis to power fault-tolerant mode, the
EME determines if sufficient unallocated power exists to place one power
supply’s worth of power in reserve:
■
If the unallocated power budget is sufficient, the chassis sets to power
fault-tolerant mode.
■
If the unallocated power budget is not sufficient, the chassis remains
in power non-fault-tolerant mode.