Extreme Networks BlackDiamond 12800 Series, Hardware Installation Manual

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Meeting Power Requirements
BlackDiamond 12800 Series Switches Hardware Installation Guide
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In addition, some UPS devices or UPS plus software combinations provide the following functions:
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Automatically shut down equipment during long power outages.
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Monitor and log power supply status.
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Display the voltage (current draw) of the equipment.
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Restart equipment after a long power outage.
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Display the voltage currently on the line.
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Provide alarms on certain error conditions.
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Provide short-circuit protection.
Selecting a UPS
To determine UPS requirements for your switch, answer these questions:
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What are the amperage requirements?
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What is the longest potential time period that the UPS would be required to supply backup power?
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Where will the UPS be installed?
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What is the maximum transition time that your installation will allow?
NOTE
Extreme Networks recommends that you use a UPS that provides online protection.
Calculating Volt-Amperage Requirements
To determine the minimum volt-amperage requirements for your UPS:
1 Locate the voltage and amperage requirements for each piece of equipment. These numbers are
usually located on a sticker on the back or bottom of your equipment. Then multiply the numbers
together to get Volt-Amperes (VA):
VA = Volts x Amperes
2 Add the VA from all the pieces of equipment together to find the total VA requirement.
To determine the minimum volt-amperage requirements for your UPS, we recommend that you add
30% to the total.
UPS Transition Time
Transition time is the time that is necessary for the UPS to transfer from utility power to full-load
battery power. For Extreme Networks products, a transition time of less than 20 milliseconds is required
for optimum performance.
DC Power Requirements
This system should be installed in a DC-I battery return configuration. In a DC-I configuration, the
battery return conductor should be connected directly to the central office power return bus, and not to
the equipment frame or the grounding means of the equipment.