Providing a Suitable UPS Transition Time
UPS transition time
is the time required for the UPS to change from providing AC power derived from
the utility (or mains) supply to providing AC power derived from the battery backup. UPS transition
time is sometimes called
UPS transfer time
.
UPS transition times vary between UPS models and implementations, but shorter transition times are
preferred. For Extreme Networks stacking products, we recommend a UPS transition time of 20
milliseconds or less to ensure optimum performance and minimize service interruptions.
For high-availability and fault-tolerant installations in which the switches use redundant power supply
units (PSUs), we recommend that each PSU in a switch be connected to a different UPS and that each
UPS be powered by an independent AC supply. This will prevent service interruptions when a power
source is lost, or when a UPS unit fails. (Note that a single, appropriately sized UPS can power PSUs in
multiple switches. The recommendation is simply that for any given switch, the two PSUs should be
connected to different UPS units.)
Following Applicable Industry Standards
Always follow applicable industry standards.
For more information, see the following ANSI/TIA/EIA standards:
•
ANSI/TIA/EIA-568-A—the six subsystems of a structured cabling system
•
ANSI/TIA/EIA-569-A—design considerations
•
ANSI/TIA/EIA-606—cabling system administration
•
ANSI/TIA/EIA-607—commercial building grounding and bonding requirements
You can access these standards at:
.
Preparing to Install
ExtremeAccess Series: Hardware Installation Guide
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