Juniper SRX5400 Hardware Manual page 155

NOTE: The power for the cooling system comes from a different tap on the power supply,
reserved for the cooling system only. The cooling system power requirement does not
need to be deducted from the output power budget of the power supply.
Table 34 on page 156
power deficit) for an AC-powered services gateway.
maximum output power, and unused power (or a power deficit) for a DC-powered services gateway.
Table 34: Calculating Power Budget, AC-Powered Chassis
Maximum Output Power of
Power Supply
1167 W (low-line)
2050 W (high-line)
Table 35: Calculating Power Budget, DC Powered Chassis
Maximum Output Power of Power
Supply
2400 W (DIP=0)
2600 W (DIP=1)
3. Calculate input power. In this step, the input power requirements for the example configuration are
calculated. To do this, divide the total output requirement by the efficiency of the power supply as
shown in Table 36 on page 156
Table 36: Calculating System Input Power
Power Supply
SRX5400 AC
lists the power supplies, their maximum output power, and unused power (or a
Maximum Output Power for System
1167W x 2 = 2334 W
(2+1 Redundancy)
2050 x 2 = 4100 W
(2+1 Redundancy)
Maximum Output Power for System
2400 W
(1+1 Redundancy)
2600W
(1+1 Redundancy)
Here we include the power drawn by the cooling system.
Power Supply Efficiency
89 %
Table 35 on page 156 lists the power supplies, their
1
Input Power Requirement
2095/0.89 = 2354 W
Unused Power
2334 - 2095 = 239W
4100 - 2095 = 2005W
Unused Power
2400 - 2095 = 305 W
2600 - 2095 = 505 W
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