Redundant Switch - Applications Guide March 22, 1999
10
MONITORING HIGH AVAILABILITY
Redundant Switch of the Redundant Smart-UPS System checks the availability of both Smart-UPS units to
deliver power to the load. You can view the availability of both UPS-A and UPS-B at the Redundant Switch
front panel (refer to the Redundant Switch User’s Manual- part number).
The Smart-UPS units are preset to self-test every two weeks. Self tests of both Smart-UPS units can also be
executed when a self test is initiated locally on UPS-A. If one Smart-UPS unit fails its self test, the
Redundant Smart-UPS System is still providing clean AC power and battery back up functionality through
the other Smart-UPS unit. Check the installation to further diagnose the situation / restore the System,
SWITCHING FROM PREFERRED SOURCE TO REDUNDANT SOURCE
Redundant Switch switches load delivery to the redundant Smart-UPS when it detects that the power feed
from Source A is unable to deliver power to the load. In this case, the availability of the system drops from
very high (with both Smart-UPS available to provide AC power and battery back up) to the standard
availability power protection afforded by a single Smart-UPS. Examine the Redundant Switch front panel or
the front panels of the Smart-UPS units to determine availability..
MONITORING THE AVAILABILITY OF THE REDUNDANT SMART-UPS
Redundant Switch continuously monitors the power delivery capability of the redundant Smart-UPS. When
Redundant Switch senses that its power feed from Source B is unable to deliver power to the load (if it were
to be engaged) it indicates so on the front panel (AC Source LED Indicators). Examine the Redundant
Switch front panel or the front panels of the Smart-UPS units for details. In this case, the availability of the
system drops from very high (with both Smart-UPS available to provide AC power and battery back up) to
the standard availability power protection afforded by a single Smart-UPS.
EXTENDED BLACKOUT
During an extended blackout to the preferred (engaged) Smart-UPS, Redundant Switch remains engaged to
the preferred Smart - UPS (UPS-A). Redundant Switch does not engage the alternate Smart - UPS (UPS-B)
automatically since it does not sense an AC power fault from the UPS-A (which switches to On Battery).
When the UPS-A battery runs low, it continues to supply the load, further draining. When the UPS-A
battery is fully depleted, Redundant Switch senses that the load will be dropped, and switches immediately
to selecting Source B (UPS-B), thereby keeping the load powered.
After power is restored to the UPS-A, Redundant Switch switches back to selecting power from this UPS.
UPS-B is tapped to deliver AC power in this case. Without the safe shutdown functionality that the power
protection system supplies to a server load via PowerChute plus, Redundant Switch acts as a static transfer
switch. The user can expect to use the run time of both UPS-A and UPS-B. Ideally, different phases of AC
power should be used to feed UPS-A and UPS-B. This way, an extended blackout to one phase can occur
and as long as the other phase remains up, the load will not suffer downtime.
(68 pages)
(28 pages)
(1 pages)
Manymanuals.com
Manymanuals.de
Manymanuals.fr
Manymanuals.it
Manymanuals.pl
Manymanuals.cz
Manymanuals.es
Manymanuals-pt.com
Comments to this Manuals