Dell PowerConnect J-8208, Hardware Manual

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NOTE: If the input voltage is high line (200–220 VAC), the output wattage
of a 2000 W AC power supply is 2000 W.
If the input voltage is low line (100–120 VAC), the output wattage of a
2000 W AC power supply is 1200 W.
For example, for a switch fully loaded with 8-port SFP+ line cards and using N+1 power
redundancy with high-line input voltage, the required power supplies (N):
= (total power requirement) / (output wattage of power supply)
= (5200 W) / (2000 W)
= 2.6
= 3 (rounded up)
For a switch fully loaded with 8-port SFP+ line cards, using N+N power redundancy
with high-line input voltage, and running Junos OS Release 10.2, the required power
supplies (N):
= (total power requirement) / (output wattage of power supply)
= (4800 W) / (2000 W)
= 2.4
= 3 (rounded up)
4.
Add the number of power supplies needed to achieve the required power redundancy:
• To achieve N+1 power redundancy, add a single power supply.
For example, for a switch fully loaded with 8-port SFP+ line cards and using high-line
input voltage, the total number of power supplies:
= N + 1
= 3 + 1
= 4
•
To achieve N+N power redundancy, add N power supplies.
For example, for a switch fully loaded with 8-port SFP+ line cards and using high-line
input voltage, the total number of power supplies:
= N + N
= 3 + 3
= 6
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Chapter 7: Planning Power Requirements