N+N Redundancy Configuration Of Dc Power Supplies; Table 38: N+0 Dc Power Calculations For Ex4300 Switch Configurations - Juniper EX4300 Hardware Manual

EX4300 Switch Hardware Guide

Table 38: N+0 DC Power Calculations for EX4300 Switch Configurations

Number
Switch of Power
Configuration Supplies
24-port 1
EX4300 switch
2
32-port 1
EX4300 switch
2
48-port 1
EX4300 switch
2

N+N Redundancy Configuration of DC Power Supplies

58
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))
If two power supplies are installed in the switch:
System power budget = (Sum of the output wattage of the two power supplies) –
(10% of the output wattage of the installed power supply)
System power budget = PSU
Table 38 on page 58 lists the N+0 power calculation for EX4300 switches that use 550 W
DC power supplies.
System
Total Power Power Budget
(in watts) (in watts)
550 550
1100 1045
550 550
1100 550
550 550
1100 1045
You can configure your switch for N+N redundancy, in which N power supplies can be
removed or fail and the remaining N power supplies continue to supply power for the
switch without interruption.
You can configure the power management software to manage switch power for N+N
redundancy. When you configure power management for N+N redundancy, half of the
total power available (N) is held as reserve power while the other half (N) is available
for immediate consumption. If the switch configuration changes and requires additional
power, then additional power is drawn from the reserve power, and the switch no longer
has N+N power supply redundancy. This condition raises a minor alarm. 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 Understanding Power Management on EX
Series Switches.
(W) + PSU (W) – (0.10 x (PSU(W))
0 1
Backup Base
Power (in Power (in
watts) watts)
0 150
0 150
0 149
550 160
0 175
0 175
Copyright © 2015, Juniper Networks, Inc.
Available PoE Ports
Power (in Enabled
watts) for PoE+
400 13
895 24
N/A N/A
N/A N/A
375 12
870 29