Each DC power supply weighs approximately 3.8 lb (1.7 kg) and consists of one DC input (–48 VDC and return), one 40 A (–48 VDC) circuit breaker, a fan, and LEDs to monitor the status of the power supply. Figure 1 shows the power supply. Each DC power supply has a single DC input (–48 VDC and return) that requires a dedicated facility circuit breaker.
Figure 1: DC Power Supply
For DC power electrical specifications, see the SRX 5600 Services Gateway Hardware Guide.
In the DC power configuration, the device contains either two or four DC power supplies (see Figure 1) located at the rear of the chassis in slots PEM0 through PEM3 (left to right). You can upgrade your DC power system from two to four power supplies.
Four power supplies provide full redundancy. If a DC power supply in a redundant configuration is removed or fails, its redundant power supply takes over without interruption. The DC power supply in PEM2 serves as redundant to the DC power supply in slot PEM0, and the DC power supply in PEM3 serves as redundant to the DC power supply in slot PEM1. If only two DC power supplies are installed, they must be installed in slots PEM0 and PEM1 or in slots PEM2 and PEM3.
Table 1: Power Supply Redundancy and Power Distribution
Each DC power supply faceplate contains three LEDs that indicate the status of the power supply (see Table 2). The power supply status is also reflected in two LEDs on the craft interface. In addition, a power supply failure triggers the red alarm LED on the craft interface.
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Note: An SCB must be present for the PWR OK LED to go on. |
Table 2: DC Power Supply LEDs