Juniper SRX550, Hardware Manual

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CHAPTER 6
Power System Description
IN THIS CHAPTER
SRX550 Services Gateway Power Supply | 28
SRX550 Services Gateway Power Supply
The SRX550 Services Gateway uses either one AC or one DC power supply unit (PSU). The services
gateway is equipped with one AC power supply (see Figure 10 on page 29 ) for non-power redundancy. A
second PSU is optional (sold separately) for power redundancy. A second PSU can be used to meet power
requirements exceeding the wattage provided by a single PSU (a nonredundant configuration). The two
power supplies, either both AC or both DC, will load-share and provide power redundancy to the services
gateway, increasing its availability and reliability. If one power supply fails or is removed, the other power
supply redistributes the electrical load without interruption. The services gateway reassesses the power
required to support its configuration and issues errors if the available power is insufficient.
Figure 11 on page 29 shows the diagram of the DC power supply.
CAUTION: Do not mix AC and DC power supplies within the same services gateway
because this can damage the device.
All power supplies are hot-swappable and support single or dual redundant power supply versions. Each
power supply is cooled by the system’s fans.
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