Powerware Plus 80 - Page 14

Your UPS functions automaticatly to supply AC electrical power to your crittcal
load. The UPS ahvays operates in one of three modes:
l In Norma/ mode, the critical load is supplied by the inverter, which
derives its power from rectified utility AC power. In this mode, the
rectifier also provides charging current for the battery.
- In Saffery mode, the battery cabinet provides DC power, which
maintains inverter operation. The battery supports the critical load.
l In &pass mode, the critical load is directly supported by the utility
through an isolation transfomw.
The UPS continually monitors itself and the incoming utility power, and automatically
swftches between these modes as required, with no operator imerventfon. The
sophisticated detection and switching logic inside the UPS ensures that operating mode
changes are automatic and transparent to the critical load. The UPS switches operating
modes in response to these sysfem even&
l A command is an intervention that is externally initiated by an operator
or by some site action. A command causes the UPS to switch
operating modes: it usually does not require any further actton by you.
l A nofice is a minor system event that may or may not &ire your
attention.
l An a/arm is a system event that requires immediate operator
intervention.
System events, alarm horns, and indicator lights are described in ‘Responding to System
Events’ on page 45.
Powerware Plus 80 UPS Operators Manual
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