Juniper MX480 Hardware Manual page 199

Both normal-capacity and high-capacity MX480 chassis with DC power supplies are zoned, meaning that
certain components are powered by specific power supplies (see
zoning). When calculating power requirements, be sure that there is adequate power for each zone.
For an AC-powered chassis, there is one overall zone. Two AC power supplies are mandatory for high-line,
and three AC power supplies are mandatory for low-line power.
Table 86: MX480 DC Zoning
Zone
Zone 0
Zone 1
The following sample configuration shows a DC-powered MX480 with:
Two 16-port 10-Gigabit Ethernet MPCs with SFP+(slots 0 and 1)
Two SCBs with two (redundant) RE-1800x2 routing engines (SCB slot 0 and SCB slot 1)
One DPCE-R-4XGE-XFP (slot 3)
High-capacity cooling system
NOTE: The high-capacity cooling system satisfies cooling requirements of MPCs, and must
be used for proper cooling.
Power Supply (PEM)
PEM 0 or 2
PEM 1 or 3
Table 86 on page 201 for information on
Components Receiving Power
Fan Tray
DPC/MPC slots 0 and 1
SCB slots 0 and 1
Fan Tray
DPC slots 2 through 5
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