Tripp-Lite PDUMH30AT Manual Del Propietário página 19

Configuration and Operation
Automatic Transfer Switch
When the Primary and Secondary inputs are both connected to Tripp Lite UPS
Systems, the PDU operates as an Automatic Transfer Switch, providing redundant
input power for high-availability applications. Under normal operating conditions, the
PDU will distribute power from the Primary input source, switching to the Secondary
input source under certain conditions. The PDU will switch to the Primary source
whenever it is "Good," according to the PDU input voltage definitions (see below).
Preferred Configuration
The Automatic Transfer Switch function
provides increased availability when the
Primary and Secondary inputs of the
Utility A
Utility B
PDU are connected to separate
Tripp Lite UPS Systems that are
Facility Circuit
Facility Circuit
connected to separate utility power
sources. For maximum availability,
Tripp Lite recommends using matching
Primary UPS
Secondary UPS
SmartOnline UPS Systems with pure
Primary Input Cord
Secondary Input Cord
sine wave output for the Primary and
Secondary input power sources. The
automatic transfer switch function will
Critical Equipment
be compromised if the primary and
PDUMH30AT
Loads
secondary inputs are connected to the
same utility power source.
Warning: DO NOT connect the primary input to a line-interactive UPS, due to
transfer-time issues, or to any source that does not supply a pure sine wave.
Such sources may be used to power the secondary input.
Automatic Transfer Switch Source Selection
The PDU will power up if one of the input sources is greater than the minimum
startup voltage. In normal operation (after power-up), if the presently selected source
(primary or secondary) degrades to a lesser condition, the unit should switch to the
alternate source, if that source is of better quality. The unit prefers the primary
source, and will always switch to it in the event both sources are of the same (fair or
good) quality. If the present source is becoming bad and the alternate source is at
least fair, the unit will switch to the alternate source.
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