Cisco 7600-SIP-400 - SPA Interface Processor 400 Installation Manual page 199

Chapter 5 Removal and Replacement Procedures
For proper 4000W DC-input redundant power configuration, all three pairs of input wires for one 4000W
Note
DC-input power supply must come from the same battery system (A feed); all three pairs of input wires
for the other 4000W DC-input power supply must come from another battery system (B feed).
Note For multiple DC input power supply, each DC input must be protected by dedicated circuit breaker or
fuse. The circuit breaker or fuse should be sized according to the power supply input rating and local or
national electrical code requirements.
Warning When installing the unit, the ground connection must always be made first and disconnected last.
The 4000 W DC-input power supply provides voltages of 2700 W or 4000 W. Select 2700 W by wiring
Note
any two positive (+)/negative (-) terminal pairs in any sequence. Select 4000 W by wiring all three
terminals. The Cisco IOS software detects the wired inputs and sets the proper system power.
The procedure that follows provides instructions for installing PWR-4000-DC power supplies in
Note
redundant 2700 W or 4000 W configurations. If you are installing a single power supply, install it in the
left-side position that corresponds to the chassis labeling "Power 1."
You should allow a minimum of 2.5 to 3 inches (63.5 mm to 76.2 mm) of space between the side of the
Note
power supply and any obstructions (such as the side of an enclosed equipment rack). This space is needed
to install and secure the DC-input power cables correctly. Incorrectly routing the DC-input power cables
can cause airflow blockage into the power supply and inadequate strain relief in the cables. The exact
amount of space required depends upon the gauge and flexibility of the DC-input power cables you are
using.
Follow these steps to install a DC-input power supply:
Power supply ground is required.
Step 1
Note The system ground connection with the PWR-4000-DC power supply in a Cisco 7609 router is provided
by the PWR-4000-DC power supply ground. Additionally, you can connect a system (earth) ground.
Note When using a PWR-4000-DC power supply in a Cisco 7609 router, you must always connect the
PWR-4000-DC power supply ground.
OL-4503-26
Removing and Replacing the Power Supply
Cisco 7600 Series Router Installation Guide
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