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Power Considerations
AC and DC power supplies, and an optional redundant (second) power supply, are available for most
systems.
Note
Refer to your hardware installation guide for AC and DC power specifications and for redundant power
supply availability.
Be careful when connecting systems to the supply circuit so that wiring is not overloaded.
AC Power
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DC Power
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Redundant Power
If your system includes an optional redundant (second) power supply, connect each of the two power
supplies to different input power sources. Failure to do so makes the system susceptible to total power
failure in the event that one of the power supplies fails.
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Ensure that your footing is solid and the weight of the system is evenly distributed between your
feet.
Lift the system slowly, keeping your back straight. Lift with your legs, not with your back. Bend at
the knees, not at the waist.
Do not attempt to lift the system with the handles on he power supplies or on any of the cards. These
handles are not designed to support the weight of the system.
Depending on the weight of the system, more than one person might be required to lift it.
The system is designed for connection to TN power systems. A TN power system is a power
distribution system with one point connected directly to earth (ground). The exposed conductive
parts of the installation are connected to that point by protective earth conductors.
Ensure that the plug-socket combination is accessible at all times, because it serves as the main
disconnecting device.
Connect DC-input power supplies only to a DC power source that complies with the safety extra-low
voltage (SELV) requirements in the UL 1950, CSA 950, EN 60950, and IEC 60950 standards.
Incorporate a readily accessible two-poled disconnect device in the fixed wiring.
Ensure that power is removed from the DC circuit before installing or removing power supplies.
Tape the switch handle of the DC circuit breaker in the off position.
Use only copper conductors to connect to a DC terminal block.
Use approved wiring terminations, such as closed-loop or spade-type with upturned lugs, when
stranded wiring is required. These terminations should be the appropriate size for the wires and
should clamp both the insulation and the conductor.
Ensure that no exposed portion of the DC-input power source wire extends from the terminal block
plug. An exposed wire can conduct a harmful level of electricity.
Regulatory Compliance and Safety Information for the Cisco 7500 Series Routers
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