Cisco Nexus 7706, Руководство по установке оборудования

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• Combined power—Do not add any power supplies to the number of power supplies calculated for the available
power in Step 2. This power mode does not provide power redundancy, so no extra power supplies are needed.
• Power supply redundancy ( n +1 redundancy)—Add one power supply (reserve power supply). This form of power
redundancy provides a reserve power supply that can replace any active power supply that goes offline.
• Input source redundancy (grid redundancy)—Add enough power supplies (reserve power supplies) to at least equal
the total output of the active power supplies (number of power supplies calculated in Step 2). Typically, you would
double the number of power supplies. You must plan for a second power source for the reserve power supplies. For
example, if you calculate that you need two 3-kW power supplies for 6 kW of available power, you need another
two 3-kW power supplies for 6 kW of reserve power (for a total of four 3-kW power supplies used for available and
reserve power).
• 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 you have at least one extra power supply. 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. For example, if you calculate that you need two 3-kW power
supplies for 6 kW of active power, then you need another two 3-kW power supplies for 6 kW of reserve power (for
a total of four 3-kW power supplies used for active and reserve power). 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 2: Circuit Requirements for 3-kW Power Supplies
Requirement for Each Circuit Number of
Circuits Power Supply
AC Power Supplies
20 A at 110 VAC or 220 VAC 1 (N77-AC-3.0KW) 3-kW power supply
DC Power Supplies
20A 1 (N77-DC-3.0KW) 3-kW power supply
Table 3: Circuit Requirements for 3.5-kW HVAC/HVDC Power Supplies
Requirement for Each Circuit Number of
Circuits Power Supply
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 1 (N77-HV-3.5KW) 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).
Cisco Nexus 7706 Hardware Installation Guide
9 OL-31330-01
Preparing the Site
Planning for Power Requirements