Juniper MX480, Руководство по оборудованию

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Figure 12: High-Capacity AC Power Supply
AC OK
DC OK
PS
FAIL
For more information about the AC power specifications, see the MX480 3D Universal
Edge Router Hardware Guide .
WARNING: The router is pluggable type A equipment installed in a
restricted-access location. It has a separate protective earthing terminal
(sized for UNC 1/4-20 ground lugs) provided on the chassis in addition to the
grounding pin of the power supply cord. This separate protective earthing
terminal must be permanently connected to earth.
AC Power Supply Configurations
The MX480 high-capacity and normal-capacity power supplies each support either of
the following AC power configurations:
•
In the low-line (110 V) AC power configuration, the MX480 router contains three or
four AC power supplies (see
Figure 11 on page 45 ), located horizontally at the rear of
the chassis in slots PEM0 through PEM3 (left to right). Each AC power supply provides
power to all components in the router. When three power supplies are present, they
share power almost equally within a fully populated system. Four AC power supplies
provide full power redundancy. If one power supply fails or is removed, the remaining
power supplies assume the entire electrical load without interruption. Three power
supplies provide the maximum configuration with full power for as long as the router
is operational. The low-line configuration requires three power supplies and the fourth
power supply provides redundancy. With high-capacity power supplies, you must have
a minimum of three power supplies installed in the router.
• In the high-line (220 V) AC power configuration, the MX480 router contains two or
four AC power supplies (see
Figure 11 on page 45 ), located horizontally at the rear of
the chassis in slots
PEM0
through
PEM3
(left to right). In a high-line AC power
configuration, each AC power supply provides power to all components in the router.
When two or more power supplies are present, they share power almost equally within
a fully populated system. Four AC power supplies provide full power redundancy. If
one power supply fails or is removed, the remaining power supplies assume the entire
electrical load without interruption. Two power supplies provide the maximum
Copyright © 2019, Juniper Networks, Inc. 46
MX480 Universal Routing Platform Hardware Guide