Uninterruptible Power Supply Requirements; Ups Features; Calculating Amperage Requirements; Ups Transition Time - Extreme Networks BlackDiamond 8810 Hardware Installation Manual

Safety Information

Uninterruptible Power Supply Requirements

An uninterruptible power supply (UPS) is a device that sits between a power supply (such as a wall
outlet) and a device (such as a switch) to prevent outages, sags, surges, and bad harmonics from
adversely affecting the performance of the device.

UPS Features

A UPS traditionally can perform the following functions:
Absorb relatively small power surges.
Smooth out noisy power sources.
Continue to provide power to equipment during line sags.
Provide power for some time after a blackout has occurred.
In addition, some UPS or UPS plus software combinations provide the following functions:
Automatically shut down equipment during long power outages.
Monitor and log power supply status.
Display the voltage (current draw) of the equipment.
Restart equipment after a long power outage.
Display the voltage currently on the line.
Provide alarms on certain error conditions.
Provide short circuit protection.

Calculating Amperage Requirements

To determine the size of UPS that you need, use the following procedure:
1 To find Volt-Amps (VA), 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 VA:
VA = Volts x Amperes
2 Add the VA from each piece of equipment together to find the total VA requirement.
To determine the minimum 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.
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