Cisco Nexus 7702 Hardware Installation Manual page 17

Preparing the Site
• Full redundancy (n+1 and grid redundancy)—Add enough power supplies (reserve power supplies) to at least equal
the output of the active power supplies (number of power supplies calculated in Step 2). For power supply (n+1)
redundancy, ensure that . For input-source (grid) redundancy, you will probably double the number of power
supplies. You must plan for a second power source with at least the same amount of input power for the reserve
power supplies. Either one of the reserve power supplies can replace any of the active power supplies.
Step 4 Be sure that the power source circuits are dedicated to the switch and not to other electrical equipment.
For combined power mode (no power redundancy) or power supply (n+1) redundancy, you need only one dedicated
circuit. The requirements for each circuit are listed in the following table.
Table 1: Circuit Requirements for 3-kW Power Supplies
Power Supply
AC Power Supplies
3-kW power supply
DC Power Supplies
3-kW power supply
Table 2: Circuit Requirements for 3.5-kW HVAC/HVDC Power Supplies
Power Supply
3.5-kW
HVAC/HVDC power
supply
Step 5 Plan the placement of the input power receptacles within reach of the power cables used for each power supply (see the
following table for the maximum distances).
Typically, power receptacles are placed on the rack with the switch. If the DC power source is further than allowed by
the DC power cables, you can install a power interface unit (PIU) in the rack with the switch and connect that to the
power source with other cabling.
Power Supply
All AC power supplies
HVAC/HVDC 3.5-kW power
supplies
DC 3-kW power supplies
Number of
Circuits
(N77-AC-3.0KW) 1
(N77-DC-3.0KW) 1
Number of
Circuits
(N77-HV-3.5KW) 1
Maximum Distance Between Receptacle and Power Supply
12 feet (3.6 m)
14 feet (4.26 m)
Determined by the length of the power cord that you supply.
Planning for Power Requirements
Requirement for Each Circuit
20 A at 110 VAC or 220 VAC
20A
Requirement for Each Circuit
20 A at 110 VAC, 210 VAC, 220/230 VAC and
277 VAC or 20 A at 210 VDC, 220/240 VDC
and 380 VDC
Cisco Nexus 7702 Hardware Installation Guide
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