Juniper EX4300 Series Hardware Manual page 127

N+N Redundancy Configuration of DC Power Supplies
You can configure your switch for
N power supplies continue to supply power for the switch without interruption.
and the remaining
You can configure the power management software to manage switch power for
When you configure power management for
held as reserve power while the other half (
configuration changes and requires additional power, then additional power is drawn from the reserve
power, and the switch no longer has
If the condition is not corrected within 5 minutes, then a major alarm is issued.
For more information about how power management allocates power to chassis components when
power is insufficient, see
Depending on the power supplies installed in the switch, you can determine the system power budget.
• If one power supply is installed in the switch:
• System power budget = Output wattage of the installed power supply (PSU(W))
• Backup power available = 0 W
A minor alarm is raised as switch has no
• If two power supplies are installed in the switch:
• System power budget = (Output wattage of one power supply) – (5% of the output wattage of
one power supply)
System power budget = PSU(W) – (0.05 x PSU(W))
• Backup power available = (Output wattage of one power supply) – (5% of the output wattage of
one power supply)
System power budget = PSU(W) – (0.05 x PSU(W))
Table 50 on page 118 lists the
supplies.
NOTE: The DC power supply in the switch does not support Power over Ethernet (PoE); you can
use either an external power injector or an AC power supply to supply power to PoE devices that
you connect to the switch. 32-port EX4300 switches does not support Power over Ethernet
(PoE).
N + N redundancy, in which N power supplies can be removed or fail
N + N redundancy, half of the total power available ( N ) is
N ) is available for immediate consumption. If the switch
N + N power supply redundancy. This condition raises a minor alarm.
Understanding Power Management on EX Series
N + N power supply redundancy.
N + N power calculation for EX4300 switches that use 550 W DC power
N + N redundancy.
Switches.
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