Juniper SRX 5800, Hardware Manual

Page: 196 / 536

Table 55: Calculating Power Budget for SRX5800 Services Gateway with Six SPC2s and One SPC3
Zone 1 Unused
Power
2
Zone 0 Unused
Power
1
Maximum Power
Output of a
System
Maximum Power
Output of a Power
Supply Power Supply
4100-3720=380 W
unused power
4100-3700=400 W
unused power
8200 W (2+2 with
two feeds)
4100 W (with two
feeds)
SRX5800 AC
high-capacity
4100-3720=380 W
unused power
4100-3700=400 W
unused power
8200 W (2+2 with
two feeds)
4100 W (with two
feeds)
SRX5800 DC
high-capacity
1
For this configuration, power output is 3700 W.
2
For this configuration, power output is 3720 W.
3. Calculate input power. In this step, the input power requirements for the example configuration are
calculated. To do this, divide the total power output requirement by the efficiency of the power supply
as shown in Table 56 on page 197 .
Table 56: Calculating Input Power for SRX5800 Services Gateway with Six SPC2s and One SPC3
Input Power Requirement
Power Supply
Efficiency
1
Power Supply
Zone 0: 3700/0.88= 4204 W ~88 % SRX5800 AC high-capacity
Zone 1: 3720/0.88= 4227 W
Zone 0: 3700/0.86= 4302 W 86 % SRX5800 DC high-capacity
Zone 1: 3720/0.86= 4325 W
1
These values are at full load and nominal voltage.
4. Calculate thermal output (BTUs) for the system. To calculate this value, add the total input power
requirement (in watts) for the two zones together and multiply the sum by 3.41 as shown in
Table 57 on page 197 .
Table 57: Calculating Thermal Output for SRX5800 Services Gateway with Six SPC2s and One SPC3
Thermal Output (BTUs per hour) Power Supply
(4204 + 4227) * 3.41 = 18,618 BTU/hr SRX5800 AC high-capacity
(4302 + 4325) * 3.41 = 19,050 BTU/hr SRX5800 DC high-capacity
197