Extreme Networks Summit 200-24, Руководство по установке оборудования

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Applicable Industry Standards
Extreme Networks Consolidated "i" and "e" Series Hardware Installation Guide 53
Calculating Amperage Requirements
To determine the size of UPS that you need, use the following procedure:
1 To find VA (Volt-Amps), 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.
Applicable Industry Standards
For more information, see the following ANSI/TIA/EIA standards:
• ANSI/TIA/EIA-568-A—discusses the six subsystems of a structured cabling system.
• ANSI/TIA/EIA-569-A—discusses design considerations.
• ANSI/TIA/EIA-606—discusses cabling system administration.
• ANSI/TIA/EIA-607—discusses commercial building grounding and bonding requirements.
You can access these standards at http://www.ansi.org/ or http://www.tiaonline.org/ .
Planning for Optical Budgets
This section provides information about the optical and system budgets for GBICs and mini-GBICs.
Optical Budgets for Mini-GBICs
The total optical system budget for the SX mini-GBIC is 11.5 dB. Extreme Networks recommends that 3
dB of the total budget be reserved for losses induced by cable splices/connectors and operating margin.
While 8.5 dB remains available for cable induced attenuation, the 1000BASE-SX standard specifies
supported distances of 275 meters over 62.5 micron multimode fiber and 550 meters over 50 micron
multimode fiber. There is no minimum attenuation or minimum cable length restriction.
The total optical system budget for the LX mini-GBIC is 13.5 dB. Measure cable plant losses with a 1310
nm light source and verify this to be within budget. When calculating the maximum distance attainable
using optical cable with a specified loss per kilometer (for example 0.25 dB/km) Extreme Networks
recommends that 3 dBm of the total budget be reserved for losses induced by cable splices/connectors
and operating margin. Thus, 10.5 dB remains available for cable induced attenuation. There is no
minimum system budget or minimum cable length restriction because the maximum receive power is