MX480 DC Power Supply Description

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 circuit breaker.

For high capacity power supplies, we recommend that you provision 60 A or 75A per feed, depending on the selected DIP switch setting.

Figure 1: DC Power Supply

Figure 2: High-Capacity DC Power Supply

DC Power Supply Configurations

In the DC power configuration, the MX480 router 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 shows the components that are powered by each DC power supply slot. It applies to existing and high-capacity power supplies.