Juniper MX480 Hardware Manual page 35

Chapter 1: MX480 Router Overview
(left to right). Each AC power supply provides power to all components in the
PEM3
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 instantly assume
the entire electrical load without interruption. Two power supplies provide the maximum
configuration with full power for as long as the router is operational.
In the DC configuration, two power supplies are required to supply power to a fully
configured router. One power supply supports approximately half of the components
in the router, and the other power supply supports the remaining components. The
addition of two power supplies provides full power redundancy. If one power supply
fails or is removed, the remaining power supplies instantly assume the entire electrical
load without interruption. Two power supplies provide the maximum configuration
with full power for as long as the router is operational.
Cooling system—The cooling system has redundant components, which are controlled
by the host subsystem. If one of the fans fails, the host subsystem increases the speed
of the remaining fans to provide sufficient cooling for the router indefinitely.
Related MX480 Router Description on page 3
Documentation
MX480 Chassis Description on page 7
Copyright © 2011, Juniper Networks, Inc. 5