4
InatypicalofficeenvironmenttheseprinterscanremaininAuto‐Offmorethan70%ofthetime,when
theprinterandtheuserenvironmentareconfiguredcarefully.
ThepowerstatesdiagramidentifiestheeventsthatcausetheprintertoenterandexittheAuto‐Off
state:
1) The
arrivalofaPrintJoborpressingthePowerButtonwillwaketheprinterfromAuto‐Off.
Thoughthesecauseanincreaseinenergyconsumption,theyarenecessaryactivitiesfora
printer.
2) WhentheSleepTimerexpiresandtheWake/Auto‐OnisconfiguredforNetworkPort,the
printer
entersAuto‐offandminimizesenergyusage.Forenergysavings,thiseventshouldbe
maximizedbymakingtheSleepTimerasshortasreasonable.
3) WhenMaintenanceEventsoccur,theprintergenerallymustleaveAuto‐OffandentertheSleep
powerstatetoprocesstheseevents.WhentheSleepTimerexpires,
theprinterwillreturnto
Auto‐Off.TheseMaintenanceEventsaretheprimarycauseofunnecessarywake‐upsfrom
Auto‐Offthatleadtoexcessenergyconsumption.
USBandAuto‐Off/Auto‐On
WheninAuto‐Off,inordertokeepenergyconsumptionbelow1W,theUSBcircuitryisentirelypowered
down.TheM500andM600printerscannot,therefore,automaticallyawakefromAuto‐Offforprint
jobsfromtheUSBport.Byextension,anyaccessoriessuchasbadgereadersorexternalnetwork
devices
connectedviaUSBareinactiveduringAuto‐Offandcannotawakentheprin ter.Whenthese
accessoriesareinuse,itwillbenecessarytousethepowerbuttontoawakentheprinterfirst.
Theprintershouldalsobeawakened,bypressingthepowerbutton,beforeinitiatinganinstallationover
USB.
ePrintandAuto‐Off/Auto‐On
HP’sePrinttechnologyforemailingprintjobsdirectlytotheprinterreliesuponactiveinteraction
betweentheprinterandtheePrintserversintheInternet.WhentheprinterisinAuto‐Off,theinternal
processestoconnecttotheePrintserversaresuspendedandwillnotresumeuntiltheprinterexits
Auto‐Off.ThoughthisreducesenergyconsumptionbystayinginAuto‐Offandeliminatingexcessive
networkexchanges,itwillcauseePrintjobstobedelayeduntiltheprinterisusedforotheractivities.
AnyoftheeventsthatcausetheprintertoexitAuto‐OffwillinitiatetheePrinttransactions
topickup
printjobs.NotethatthoughtheePrintjobswillbeprintedwhentheprinterawakes,jobswillbedeleted
fromtheePrintserversbetween2and24hoursaftertheyaresubmitted,dependingonload.