Juniper Networks Juniper MX-series MX960 - Manual (Page 2)

DC Power Supply
In the DC power configuration, the router contains either two or four DC power
supplies (see Figure 1 on page 2), located at the lower 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. The DC power supplies in slots PEM0 and PEM2 provide
power to the lower fan tray, DPC slots 6 through 11 , and SCB slots 1 and 2 . The DC
power supplies in slots PEM1 and PEM3 provide power to the upper fan tray, DPC
slots 0 through 5 , and SCB slot 0 .
Four power supplies provide full redundancy. If a DC power supply fails, its redundant
power supply takes over without interruption.
Each DC power supply has a single DC input (–48 VDC and return) that requires a
dedicated 80 A (–48 VDC) circuit breaker for the maximum router hardware
configuration. For information about site power preparations and connecting the
router to power and ground, see the MX960 Ethernet Services Router Hardware Guide.
For DC power supply and power system electrical specifications, see Table 1 on page
3 and the MX960 Ethernet Services Router Hardware Guide.
Figure 1: DC Power Supply
DC Power Supply Electrical Specifications
Table 1 on page 3 lists the DC power supply electrical specifications. For DC power
system electrical specifications, see the MX960 Ethernet Services Router Hardware
Guide.
2 ■ DC Power Supply
MX960 Ethernet Services Router DC Power Supply Installation Instructions