Hobo U14 User manual

©2010–2012OnsetComputerCorporation.Allrightsreserved.Onset,HOBO,andHOBOwarearetrademarksorregisteredtrademarksofOnsetComputerCorporationforitsdatalogger
productsandconfiguration/interfacesoftware.Allothertrademarksarethepropertyoftheirrespectivecompanies.
13416‐CMAN‐U14‐00x
U14DataLogger
(ModelU14‐001shown)
HOBO®U14 Data Logger User Manual
TheUfamilyofdataloggersoffersreliabilityandconvenientmonitoringforapplicationsthat
requirehigheraccuracy,betterresolution,morememory,orUSBconnectivityforfastdata
readouttoyourcomputer.
TheHOBOU14loggerrecordsanddisplaystemperatureandhumidityconditionsin
manufacturing,processing,andstorageenvironmentswherereliablemonitoringand
documentationofspecifictemp/RHconditionsarecritical.
TheHOBOU14isavailableintwoversions:U14‐001withinternalsensorsandtheU14‐002
withexternalsensors.TheHOBOU14requiresHOBOware®ProorHOBOwareLite,Version2.5
orlater.
Features
64knon‐volatilememorythatretainsdataevenifthebatteriesfail
MemoryindicatoronLCDshowshowmuchdatastoragespaceremains
BatteryLevelindicatorshowsremainingusefulbatterylife
OperatesforoneyearonthreealkalineAAAbatteriesintypicalconditions
Built‐inrelayforusewithRemoteAlarmorAutomaticDialer
DirectUSBinterfaceforlaunchinganddatareadoutusingHOBOware
Sample(logging)intervalcanbesetfromonesecondto18hours
SupportsOnset’sDataAssistants(availablewithHOBOwaresoftware)
CanbeusedwiththeOnsetU‐Shuttle(U‐DT‐1)
Internalsensormodel(U14‐001)hasinternaltemperatureandrelativehumiditysensorswith12‐bitresolution
Externalsensormodel(U14‐002)supportsthe12‐bitTemperature/10‐bitRHSensor(S‐THB‐M00x)andthe12‐bit
TemperatureSensor(S‐TMB‐M00x)
Accessories
OutdoorCase(CASE‐4x)
RemoteAlarm(ARA)
AutomaticDialer(AVD‐45)
LocationRequirements
TheHOBOU14isdesignedforanon‐condensing,non‐corrosiveenvironment.Keeptheloggerdry.Someexternalsensorscanbe
placedinharsherenvironmentsthanthelogger.Seetheexternalsensorspecificationsinthesensorusermanual.
Specifications
Environmental
Operatingtemperaturerange‐20°Cto+50°C,(‐4°Fto+122°F),0to100%RHnon‐condensing
Operatingrelativehumidityrange0to95%,non‐condensing,non‐corrosiveenvironment
LoggerCapabilities
CapacityTempandRH:21,500measurements;TempOnly:43,000measurements
Software‐selectablesamplingintervals1secondupto18hours,recordingtimesupto1year
StartProgrammablestarttime/date
RecordingmodesStopwhenfull
LaunchModesImmediate,Delayed
MemoryNonvolatileEEPROMmemoryretainsdataevenifbatteriesfail

HOBO U14 Data Logger User Manual
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PlotA:InternalTemperatureSensor
AccuracyandResolution
Specifications
LCD
Size33x50.8mm(1.3x2inches)
ElementsTemperatureandrelativehumiditysimultaneously
°Cor°F(selectablewithinhostsoftware)
Memoryremainingandbatterylevel
FlashingALERTforout‐of‐limitsconditions(selectablewithinhostsoftware),whichstopsflashing
onoffloadorreturntonormalrange
Alarms
SetpointsHighandlowsetpointsforbothtemperatureandrelativehumiditywithselectabledelays
ResetoptionsAlertconditionsresetonoffloadorreturntonormalrange
SelectableContactRelayNormallyClosedorNormallyOpen
Contactrating48VDC,1Amax
ContactresistanceLessthan1Ohm
Range0%LowBatteryRange
Communications
MethodOffloadsdatatoPCorU‐ShuttleviaUSBcable
SpeedReadoutfulllogger(64K)inlessthan30seconds
Timeaccuracy±1minutepermonthat+20°C(+68°F)
Power3AAAAlkalinebatteries,user‐replaceable
Dimensions125x92x31mm(4.9x3.6x1.2in)
Weight170g(6.0oz)withbatteries
Internal12‐BitTemperatureSensor
Measurementrange‐20°Cto+50°C(‐4°Fto+122°F)
Accuracy±0.21°Cfrom0°to50°C(±0.38°Ffrom32°to122°F);±0.13°C(0.24°F)typical(seePlotA)
Resolution0.02°C@25°C(0.04°F@77°F)(seePlotA)
Responsetime15minutes(to90%inairflowof1m/sec)
TemperatureAccuracyDriftNegligible
Internal12‐BitRelativeHumiditySensor(Userreplaceable)
Measurementrange0‐100%RH,‐20to50°C(‐4to122°F)
Accuracy+/‐2.5%from10%to90%RH(typical),toamaximumof+/‐3.5%includinghysteresis(seePlotB)
Resolution0.03%RH@25°C(77°F)
Responsetime2minutes(to90%inairflowof1m/sec)
AccuracyDrift<2%over5yearstypical
Hysteresis1%Typical
ExternalSensorsForExternalSensorSpecifications,seethesensor’susermanual
BatteryLifeThebatterieswilllastoneyearintypicalconditions(loggingintervalsof≥1minutewithweekly
offloadsandaveragetemperaturesgreaterthan10°Cor+50°F).Frequentoffloadsand/orextreme
temperatureswillreducebatterylife.Attemperaturesbelowfreezing(0°Cor+32°F),batterieswill
typicallyrequirereplacementeverysixmonths.Intheseconditionsthebatterylevelbargraph
shouldbecheckedregularly.SeeBatteryLevelIndicatorsonpage8.

TheCEMarkingidentifiesthisproductascomplyingwithallrelevantdirectivesintheEuropean
Union(EU).
TemperatureAccuracyandResolution
Themaximumreadingerrorfortheinternaltemperaturesensorsisshownatright.Thisisaworstcase
error.Inatypicallogger,temperatureerrorswillbesubstantiallylower.NISTcertificationof
temperatureaccuracyforsomesensorsisavailablefromOnset.Thetemperatureresolutionforinternal
sensorsisalsoshownatright.Resolutionisthesmallestdifferencebetweenadjacenttemperaturesteps
thattheloggercanreport.Theloggerwilltypicallyexperiencelittleornoaccuracydriftunlessthe
electroniccomponentsortemperaturesensoraredamagedmechanicallyorbyexposureto
environmentalfactorsbeyondthespecifications,suchashighheatandhumidity.

HOBO U14 Data Logger User Manual
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Plot B:InternalRHSensorAccuracy
Internal Relative Humidity Accuracy
Temperaturecompensated.
DonotexposetheinternalRHsensortofog,mist,orothercondensing
conditions.
Thelogger’srelativehumidityaccuracyfortheinternalmodelisshowninthe
plotatright.
Components
FrontBack

CircuitBoard

LCDScreen.
SeeTheLCD
Screensection
fordetails.
USBPort.
UseanOnset‐
suppliedUSB
interfacecable
toconnectthe
HOBOU14toa
computer.
ExternalSensor
Port(Model
U14‐002Only).
Connect
supported
SmartSensor
here.
ReplaceableInternalRHSensor(ModelU14‐001Only).Theinternal
relativehumiditysensorintheU14‐001mayrequirereplacementif
itisdamagedmechanicallyorbyexposuretocondensationor
chemicals.Thereplacementsensor(partnumberHUM‐RHPCB‐3or
RHPCB‐3A)isavailablefromOnsetoranOnsetAuthorizedDealer.
Seethelastpageformoredetails.
RelayTerminal(forRemoteAlarmorAutomaticDialer).TheHOBO
U14iscompatiblewithOnset’sRemoteAlarm(partnumberARA)and
AutomaticDialer(partnumberAVD‐45)availablefromOnset
ComputeroranOnsetAuthorizedDealer.Seethenextsectionfor
moredetails.
MountingHoles.Use
mountingscrews2.5cm
(1inch)aparttomount
theU14toawall.
BatteryCompartment.TheHOBOU14requires
threeAAAbatteries.OnsetComputerCorporation
stronglyrecommendstheuseoffreshalkaline
batteries.Batteriesshouldbereplacedwhenthe
BATTLEVELbargraphisdowntoonesegment,
whichindicates20%batterylifeorless.

HOBO U14 Data Logger User Manual
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SettingUptheHOBOU14
FollowtheseinstructionsforsettingupandlaunchingtheHOBOU14logger.
1. InsertthethreeAAAbatteries.Removethebatterydooronthebackoftheunitandinsertthebatteriesintheproper
direction.
2. IfyouareusingaRemoteAlarmand/orAutomaticDialer,connectittotheHOBOU14now.Otherwise,replacethe
batterycoverandgotostep3.
TheHOBOU14iscompatiblewithOnset’sRemoteAlarm(partnumberARA)andAutomaticDialer(partnumberAVD‐
45)availablefromOnsetComputeroranOnsetAuthorizedDealer.Seetheproduct’susermanualforcompletedetails.
Theinterconnectwirerangeis22AWGto14AWG.ToconnectaRemoteAlarmorAutomaticDialertotheHOBOU14:
a. Loosenthetwoscrewsontherelay
terminal.(Removethebatterydoorif
necessary.)
b. Feedthewiresthroughthesmallholeat
thebottomofthecase.
c. Feedthewiresthroughtheholesinthe
relayterminal.
d. Tightenthescrewsontheterminal.
e. Replacethebatterycompartmentcover.
f. ConnectthewirestotheRemoteAlarmorAutomaticDialerusingthefollowingwiringdiagramsasguides.
AllthreedrawingsshowtheloggerintheNormallyClosedstatewiththeAlertinactive.TheHOBOU14’scontact
closureisinitiallysetatthefactorytobeNormallyClosed,butyoucanchangethisinHOBOwaretoaccommodate
NormallyOpendevices(seetheARAUser’sManual).
IfthealertoutputisconnectedtoaremotealarmconfiguredforNormallyClosedinputs,youcanavoidfalsealarms
whentheloggerisdisconnectedbymakingatemporaryconnectionbetweenthewiresgoingtotheremotealarm.
Besuretodisconnectthistemporaryconnectionwhentheloggerisreconnectedtotheremotealarmwires.
HOBOU14withOnset’sARARemoteAlarm
NOTE:Thepolarityoftheconnectionstotheloggerdoesnotmatter.

HOBOU14withOnset’sAVD‐45AutomaticDialer
NOTE:Thepolarityoftheconnectionstotheloggerdoesnotmatter.

HOBO U14 Data Logger User Manual
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HOBOU14withOnset’sARARemoteAlarmandAVD‐45AutomaticDialer
NOTE:Thepolaritymustbeasshown.
3. IfyouhaveanExternalSensormodel(U14‐002):PlugtheexternalsensorintotheRJ‐12jackonthesideoftheHOBO
U14.Holdtheblackrubberflapdownagainsttheconnectorsoitslidesintotheport.NOTE:Thesensorreadingswillnot
bedisplayeduntiltheloggerislaunched(immediateordelayed)orthestatusischeckedusingeitherHOBOwareorthe
U‐Shuttle.Thereadingswillnotbeloggeduntilyoulaunchtheloggerlaterinthisprocedure.
4. ConnecttheU14toacomputerrunningHOBOware.PlugthelargeendoftheUSBcablesuppliedwithHOBOwareinto
aUSBportonthecomputerandplugthesmallendofthecableintothesideoftheHOBOU14.Iftheloggerhasnever
beenconnectedtothecomputerbefore,itmaytakeafewsecondsforthenewhardwaretobedetected(Windowsonly).
5. StartHOBOwareandopentheLaunchwindow.FromtheDevicemenu,selectLaunch.ConfigureLaunchparameters,
includingaLaunchdescription,logginginterval,andstarttime.ClickHelpinHOBOwarefordetailsonLaunch
parameters.
6. ConfigureAlarms(optional).UsetheAlarmfeaturetoflashawarningontheLCDifthemonitoredtemperatureor
relativehumidityfallsoutsideuser‐selectablelimits.IfthetemperatureorRHmeasuredbytheloggerfallsoutsidethe
selectedhighorlowlimit,theword‘Alert,’analertsymbol,andthetemperatureorRHmeasurementthatwentoutof
limitswillflash.
7. Ifyourequireremoteorsecondarynotificationofanalarmcondition,youcanconnectaremoteaudioalarmand/oran
AutomaticDialertothecontactclosureasdescribedinStep2.
ToaccesstheAlarmfeature,clicktheAlarmsbuttonintheLaunchwindow,whichopensthefollowingdialogbox.


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a. EnableSensorAlarms.Toenableasensoralarm,selectthedesiredsensorintheChannelbox,andthenselectthe
checkboxfortheHighAlarmand/ortheLowAlarm.Enteravaluetodefinethealarmthreshold.Youcanentera
valueintheboxorusethesliders.(Ifyouentervaluesmanually,thesoftwaremayadjustthemslightlytothe
nearestvaluessupportedbythelogger.)Youcanalsosetthenumberofsamples(30secondspersample)thatmust
bedisplayedbeforethealarmwillbetriggered.
b. SetNumberofSamples.Toavoidunintendedactivationoftherelaycontact,setthenumberofsamplestoallow
foranticipatedbreachesofthealarmthreshold.Ifthealarmistrippedandthenumberofsamplesissettomore
than1,theLCDwillindicateAlertDelayed.Ifthemeasurementisstilloutofrangewhenthenumberofsamplesis
reached,therelaycontactwillbeactivated.
NoteaboutAvoidingUnintendedRelayActivation.Insomeapplications,theenvironmentinwhichthelogger
islaunchedisinimmediateviolationofthedesiredalarmlimitandwillcauseanunintendedopeningorclosing
ofthecontactrelay.Forexample,settinganupperalarmlimitof+32°Fforafreezerapplicationandthen
launchingtheloggerinaroomatroomtemperaturewillcauseanimmediatealarmtrigger.Inthissituation,
enableaDelayedLaunchorselectanumberofsamplesthatwillresultinalongenoughdelaytoallowtimeto
transport,mount,andstabilizetheloggerinthedesiredlocation.
Othercausesofinvalidalarmswouldbefreezerdoorsbeingopenedfrequentlyordefrostcycles.Toavoid
these,setthenumberofsamplestoallowforsmallperiodsoftimewherethevalueisoutsidetherange,but
wherethealarmwillnotbetrippedunlessthevalueisoutsidetherangeforasignificantnumberofsamples.
c. LowBatteryAlarm.SelecttheBatteryAlarmcheckboxtoenabletheBatteryAlarm,whichwilltriggerifthebattery
dropsto0%.
d. AlarmReset.SelectwhetherthealarmwillbedeactivatedwhentheHosthasrelaunchedtheloggerorwhenthe
sensorreadinghasreturnedwithinlimits.
e. SetRelayContact.Ifyouareusinganexternaldevicethatwillbetriggeredbyanalarm(suchasaRemoteAlarmor
AutomaticDialer),setthedesireddefaultrelaycontactstatetoeitherNormallyClosed(relayopensduringanalarm
condition,whichisthedefault)orNormallyOpen(relayclosesduringanalarmcondition)TheARARemoteAlarm
canbesettoNormallyClosedorNormallyOpen(seeremotedeviceUser’sManualsformoredetails).NOTE:The
AVD‐45AutomaticDialerrequiresthelogger’scontactstobesettoNormallyClosed.
f. TesttheRelayAlarm.UsetheTestSetAlarmbuttontotesttherelayalarmfunction.WhenyouclicktheTestSet
Alarmbutton,theloggerwillactivatethealarmandchangetheconditionofthecontactclosure.Whenyouclick
theTestSetAlarmbutton,itchangestotheTestClearAlarmbutton.ClicktheTestClearAlarmbuttonto
deactivatethealarm.
NOTE:WhentestingthealarmwiththeAVD‐45AutomaticDialer,Onsetrecommendsthatyoumaintainthealarm
forupto7minutestoensurethattheAVD‐45AutomaticDialercompletesitsdial‐outsequence(seeAVD‐45
AutomaticDialerUser’sManualfordetails).
8. ClicktheLaunchbuttoninHOBOwaretolaunchtheHOBOU14.NOTE:IfyouremovetheexternalsensorontheU14‐
002modelafterloggingstarts,youwillneedtorelaunchtheloggerifyoureconnectasensor.
9. DisconnecttheHOBOU14fromthecomputerbyunpluggingtheUSBcable.
10. Transporttheloggertodeploymentsite.
11. Mountthelogger.TheHOBOU14isdesignedforanon‐condensing,non‐corrosiveenvironment.Makesurethelogger
isinstalledinalocationwhereitwillremaindry.Someoftheexternalsensorscanbeplacedinharsherenvironments
(seethesensormanualforspecifications).
a. Markthewallfortheplacementofthetwomountingscrews2.5cm(1inch)apart(vertically).
b. Screwinmountingscrews,leavingagapbetweenthewallandtheheadofthescrewofabout0.5cm(3/16in.).
c. Attachloggerbyaligningitwiththescrews,andthenpushinanddowntolockinplace.
12. IfyouhaveanExternalSensormodel(U14‐002),mounttheExternalSensors(seethesensorusermanual).

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Insomeapplications(suchasarefrigerator,freezer,cleanroom)itmaybemoreconvenienttopermanentlymountan
externalsensoratthesite.Besuretoplacetheremotesensorinalocationthatisrepresentativeofthetarget
measurementlocationandallowsfreeflowofair(bewareofanydraftscausedbyvents,doors,etc).
Ifyoupermanentlymountthesensorandlaterhavetodisconnectitfromtheloggerforreadout,selectDelayedLaunch
whenyourelaunchtheloggertoallowtimetoreconnectthesensorbeforetheactuallaunchtime.
13. ReadouttheHOBOU14asdescribedinthenextsection.Whenthememoryisfull,oranytimeyouwanttoviewthe
data,readouttheHOBOU14usingHOBOware.
ReadingOuttheHOBOU14
NOTE:IfyouareusingtheU‐Shuttletoreadoutthelogger,seetheU‐ShuttleUserManualforspecificinstructions.
TooffloaddatafromtheHOBOU14:
1. Optional:Disconnecttheloggerfromtheexternalsensor,RemoteAlarmorAutomaticDialer.
2. Transporttheloggertothelocationofthecomputer.
3. Connecttheloggertothecomputer.
4. OpenHOBOwaresoftwareonthecomputer.
5. Optional:Ifyouhavemorethanoneloggerconnectedtothecomputer,connecttotheHOBOU14byselectingDevice>
SelectandthenselecttheHOBOU14fromtheSelectDevicewindow.
6. Fromthemainmenu,clicktheReadouticon(orselectDevice>Readoutfromthemainmenu).
7. Iftheloggeriscurrentlylogging,youcanchoosetocontinueloggingwhileoffloadingorstoplogging.Thereadoutwill
begin.ThestatusbarintheReadoutLoggerwindowwillindicatethepercentagecomplete.
8. Whenprompted,enteranameforthefileandclickSave.ThePlotSetupDialogappears.
9. ClickPlottoviewthegraphofthedata.SeetheHOBOwareUserManualorOn‐lineHelpformoredetailsongraphing,
timeselectioninplots,andexportingdatafiles.
10. Toredeploythelogger,re‐launchitwithadelayedstartallowingenoughtimetoreturntheloggertothesite,reconnect
externaldevicesifany(ExternalSensors,RemoteAlarm,AutomaticDialer).
TheLCDScreen
Afterinstallingthebatteries,theLCDwilldisplayallsegmentsforfiveseconds.Thereafter,theLCDwilldisplaytemperatureand
%RHinformation.ThevaluesontheLCDscreenrefreshevery30seconds.ThefollowingisanoverviewoftheLCDscreen
elements.Formoredetailsonindividualelements,seeLCDIndicatorsformoredetails.
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TemperatureReading.Thisdisplaysthecurrenttemperature(FahrenheitorCelsiusasselectedinHOBOware)onthe
LCD.Internalsensorhastemperaturemeasurementrangeof‐20°Cto+50°C(‐4°Fto+122°F).Notes:Theremaybeslight
variationsbetweenthedisplayedtemperaturevalueandtheloggedvalueduetolimitsindisplayconversions.The
valuesseeninHOBOwareandtheU‐Shuttlearetheactualrecordedvaluesandthemostaccurate.Thedisplayed
temperatureontheLCDscreenmaybe±0.3°C(±0.6°F)differentthantheloggedvalue.Fahrenheitvaluesof200°and
higheraredisplayedasthreedigitswithoutadecimal(e.g.,205°F);however,thefullresolutionvaluewillberecordedin
theloggermemory(e.g.,205.4).
RelativeHumidity(RH)Reading.ThisdisplaysthecurrentRHontheLCD.Theinternalsensorhasameasurementrange
of0%to100%.
AlarmIcon.ThisdisplaysalertsasconfiguredwithinHOBOware.Specifically,ALERTindicatorsignalswhentemperature
orrelativehumiditylimitshavebeenexceeded.ALERTDELAYEDifyouhavedelayenabledandanalarmistripped.
Trianglewithexclamationmarkimmediatelyafterdelay(ifenabled)indicatesthattherelayisinanalarmstate.
BatteryLevel.Remainingbatterylevelisindicatedbyafive‐segmentbar.Thenumberofsegmentsdecreasesasbattery
leveldecreases.BatteriesshouldbereplacedwhentheBATTLEVELbargraphisdowntoonesegment,whichindicates
20%batterylifeorless.
RemainingMemory.Remainingmemoryisindicatedbyafive‐segmentbar.Thenumberofsegmentsdecreasesas
remainingmemorydecreases.NOTE:Ifthememoryisfull,theloggerwillnolongerlog.Theloggerwillcontinueto
monitorconditionshowever,andwilltriggeranalertifthereadingfallsoutsideoftheconfiguredrange.Youmust
readouttheloggerandthenrelaunchitusingHOBOwaretoresumelogging.
LCD Indicators
Alarms IfthetemperatureorRHmeasuredbytheloggerfallsoutsidetheselectedhighorlow
limit,theword‘Alert,’analertsymbol,andthetemperatureorRHmeasurementthat
wentoutoflimitswillflash.Ifyousetthenumberofsamplestogreaterthan1andthe
measuredvalueisoutsidethelimits,ALERTDELAYEDwillflashuntileitherthenumber
ofsamplesisreached(ALERTwithatrianglesymbolisdisplayed)orthealertcondition
nolongerexists.
Battery Level
BATTLEVELbargraphdowntoonesegmentindicates20%batterylifeorless.Batteries
shouldbereplaced.
Condensation (100%RH) 100%RHisdisplayedifatemperature/RHsensorisconnectedandiscoveredwith
condensation.Thesensorwillnotprovideaccuratereadingsuntilithasdriedout.
Unread Data Iftheloggerhasbeenstopped,eithermanuallyorbecausethememoryisfull,theMEM
LEFThashmarkswillblinkindicatingthereisunreaddata.
Memory
Remainingmemoryisindicatedbyafive‐segmentbar.Segmentsdecreaseasremaining
memorydecreases.TheMEMLEFTbargraphwilldecreaseasthememoryisfilled.
Whenthememoryhasbeencompletelyfilled,theMEMLEFTdisplaywillflashandall
segmentswillbeoff.TheHOBOU14willcontinuetomonitorconditionshowever,and
willtriggeranalertifthereadingfallsoutsideoftheconfiguredrange.Youmust
readouttheloggerandthenrelaunchitusingHOBOwaretoresumelogging.
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HOBO U14 Data Logger User Manual
9
LCD Indicators
MemoryDisplayStates
StateMEMLEFTHash
marks
SegmentsIllustration
StoppedOnNone

Launched/
Logging
OnNumberofsegmentsdepends
onmemoryremaining.Highest
segmentflashes.

Launch
Delaying
FlashingAllOn/Flashing

MemoryFullFlashing
(untildatais
downloaded)
AllOff
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ExternalSensorRemoved Ifanexternalsensorisdisconnectedfromthelogger,theloggerwillrecordvaluesof‐
888.88°C/‐888.88°Ffortemperatureand0%RH.
NoExternalSensor
IftheU14‐002loggerislaunchedandnoexternalsensorhasbeenconnected,the
displaywillshowdashes“‐‐‐”andwilllogfalsevalues(‐888.88°C/‐888.88°Ffor
temperatureand‐888.9%forRH).
TempOnlySensorInstalled
Ifatemperature‐onlysensorisconnected,noRHvaluewillbedisplayed.
NoRHSensorInstalledbutChannel
Active

Adisplayof‐‐%RHindicatesthatthehumiditychannelisactiveinthesoftwareand
shouldbeturnedofftomaximizememoryspace.Otherwise,theunitwillrecorda‐
888.9%RHvalueateverylogginginterval

HOBO U14 Data Logger User Manual
10
Maintenance
ReplacingBatteries
TheHOBOU14requiresthreeAAAbatteries.OnsetComputerCorporationstronglyrecommendstheuseoffreshalkaline
batteries.BatteriesshouldbereplacedwhentheBATTLEVELbargraphisdowntoonesegment,whichindicates20%batterylife
orless.Toensuredataintegrity,useHOBOwaretoreadouttheloggerandstoploggingbeforechangingbatteries.
ReplacingtheInternalRHSensor(ModelU14‐001Only)
TheinternalrelativehumiditysensorintheU14‐001loggermayrequirereplacementifitisdamagedmechanicallyorby
exposuretocondensationorchemicals.Thereplacementsensor(PartNo.HUM‐RHPCB‐3A)isavailablefromOnsetoranOnset
AuthorizedDealerforU14‐001loggerswithserialnumbersabove9847173.Note:U14‐001loggerswithaserialnumberbelow
9847173requireadifferentreplacementsensor(PartNo.HUM‐RHPCB‐3).YoucanreplacetheinternalRHsensoryourselfor
haveitreplacedaspartofaU14‐001tune‐up/calibrationservice(availablefromOnset).ContactOnsetformoredetails.
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OnsetComputerCorporation
www.onsetcomp.com
MailingAddress:
P.O.Box3450
Pocasset,MA02559‐3450
Phone:1‐800‐LOGGERS(1‐800‐564‐4377)or508‐759‐9500
Fax:508‐759‐9100
HoursofOperation:8AMto5PMET,MondaythroughFriday
Email:[email protected]