Chapter 1 Product Overview
Physical and Functional Description of Router
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Cisco 12016, Cisco 12416, and Cisco 12816 Router Installation and Configuration Guide
OL-11495-01
AC and DC Power Subsystems
A router ships with either an AC or DC powered system. Source power connects
to the power shelf at the back of the chassis which route power to the power
supplies, also referred to as power entry modules (PEMs).
Standard AC Power Shelf
The standard AC-input power subsystem consists of a single-level AC-input
power shelf that house three (2000 W original series or 2400 W enhanced series)
AC power supplies which supply full redundant power to the router. Figure 1-2
shows the standard power shelf housing original series 2000 W power supplies.
The power supplies participate in an N+1 redundant current-sharing scheme that
is divided among all three power supplies. If one power supply fails, the system
can continue to operate temporarily, (depending on your system configuration)
with the remaining two power supplies. Failed power supplies should be replaced
as soon as possible to ensure full redundancy.
Caution To ensure that the chassis configuration complies with the required power
budgets, use the on-line power calculator. Failure to properly verify the
configuration may result in an unpredictable state if one of the power units fails.
Contact your local sales representative for assistance.