Extech Instruments HD755 User manual

USERGUIDE
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HeavyDuty
DifferentialPressureManometer
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ModelHD755
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HD755-EU-EN V1.7 7/13
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Introduction
CongratulationsonyourpurchaseoftheExtechManometerModelHD755.Thisdevicemeasures
gaugeanddifferentialpressureintherangeof±0.500psi.TheHD755offerseleven(11)unitsof
measure(userselectablebyfrontpanelpushbutton)andhasadifferentialinputthatuses
convenientquick‐disconnectfittings.AdvancedfeaturesincludeDATAHOLD,MIN‐MAX‐AVG
RECORDmode,ZERO/OFFSET,AUTOPOWEROFF,andUSBPCinterface.Thismeterisshippedfully
testedandcalibratedand,withproperuse,willprovideyearsofreliableservice.Pleasevisitour
website(www.extech.com)tocheckforthelatestversionofthisUserGuide,ProductUpdates,and
CustomerSupport.
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MeterDescription
1. P1input
2. ACadaptorjack
3. P2Input
4. LCDDisplay–Indicatesthemeasurementdata,unitofmeasure,
elapsedtimer,andfunctionsymbolsasdescribedinthismanual
5. USBPCinterfacejack(3.5mm)–Forusewithdataacquisition
software
6. UNITbutton–Presstoselecttheunitofmeasure
7. DIFbutton–Presstodisplaydifferentialpressure.Alsousedto
OFFSETthedisplayedreadings.
8. RECORDbutton–PresstoaccesstheMIN/MAX/AVGrecording
mode
9. HOLD/ZERObutton–Presstofreezethedisplayedreading.Also
usedtozerothedisplay(pressandholduntildisplayshowsallzeroes).
10. BACKLIGHT button–PresstoswitchthedisplaybacklightON.Thebacklightwill
automaticallyturnOFFafter40seconds.
11. POWERbutton–PresstoturnthemeterONorOFF
12. Batterycompartment(onrear)
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HD755-EU-EN V1.7 7/13
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Display
1. USBdataoutputactive
2. DifferentialPressureMode
3. DataHoldMode
4. Primarydisplay
5. RecordMode
6. MAX/MIN/AVGindicators
7. LowBatteryIndicator
8. Pressureunitofmeasure
9. ElapsedTimer

HD755-EU-EN V1.7 7/13
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BasicOperation
MeterPower
TheHD755usesa9Vbatteryforpower.IfthemeterdoesnotswitchonwhenthePOWER
buttonispressedorifthedisplayshowsBAT,replacethebattery.
WhenthePOWERbuttonsispressed,themeterperformsashortself‐testandrevertstothe
settingsinplacewhenthemeterwaslastturnedoff.
AutomaticPower‐offFeature
Inordertoconservebatterylife,themeterhasanautomaticpowerofffeature(after20
minutes).Todefeatthisfeature,pressandholdtheHOLDbuttonwhileturningthemeteron.
ReleasetheHOLDbuttonwhen‘n’appearsonthedisplay.Themeterwillnowremainonuntil
theuserturnsitofforuntilthebatteryweakens.NotethattheAutoPowerOFFfeaturewillbe
reactivatedthenexttimethemeteristurnedoffandthenon.
UnitofMeasure
PresstheUNITbuttontoselecttheunitofmeasure.Thismeterofferseleven(11)unitsof
measureaslistedbelow.
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UnitofMeasureDisplayicon
Poundspersquareinchpsi
InchesofMercuryinHg
Milli‐barmbar
MillimetersofMercurymmHg
Kilo‐PascalskPa
KilogramspercentimetersquaredKgcm2
InchesofwaterinH2O
FeetofwaterftH2O
CentimetersofwatercmH2O
BarsBar
Ouncespersquareinchozin2
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FittingsConnection
ConnecttubingtotheP1,P2(orboth)inputport(s).Ifbothinputsareused(differentialmode),
themeterdisplaysapositivepressurereadingiftheP1pressureisgreaterthanP2anda
negativereadingifP2isgreaterthanP1.
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ZeroAdjustandOffsetfunction
TheunitmustbekeptintheuprightpositionwhenZEROINGorwhentakingmeasurements.To
ZEROthemeter:Beforeuseandwithoutfittingsattachedtothemeter,pressandholdtheHOLD
buttonfor3secondsoruntilthedisplayshowsallzeroes.
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ToOFFSETmeterreadings:PresstheDIFbuttonwhiletakingameasurement.Subsequent
readingswillrepresentthedifferencebetweenthecurrentmeasurementandthemeasurement
thatwasonthedisplaywhentheDIFbuttonwaspressed..PresstheDIFbuttonagaintoexitthe
OFFSETfunction.
MIN‐MAX‐AVGRecordModewithElapsedTimer
TheRECORDfunctiontracksthemaximum(MAX),minimum(MIN),andaverage(AVG)readings
withatimestamp.Theelapsedtimerisdisplayedonthelowerright‐handcorneroftheLCDand
informstheuserofthetimeaMAXorMINreadingwasrecorded.
1. PresstheRECORDbuttononce.TheRECindicatorwillappearonthedisplayandthe
displayedelapsedtimerwillstart(HH:MM:SSformat[hours:minutes:seconds]).
2. PresstheRECORDbuttonagaintoviewthehighest(MAX)readingrecordedsincethe
RECORDbuttonwasfirstpressed.TheMAXindicatorandmaximumreadingwillappearon
thedisplay.TheelapsedtimerwillshowthetimeoftheMAXevent.
3. PresstheRECORDbuttonagain,theMINindicatorandtheminimumvaluewillappearon
thedisplay.TheelapsedtimerwillshowthetimeoftheMINevent.
4. PresstheRECORDbuttonagain,theAVGindicatorandtheaveragevaluewillappearonthe
display.Theelapsedtimerwillcontinuetorun.
5. Toreturntonormaloperation,pressandholdtheRECORDbuttonuntilthedisplay
indicatorsREC,MAX,etc.switchoff.
NotethatintheRECORDmode,thebacklightandthepowerbuttonsaretheonlyavailable
functions.
USBPCInterface
Themeterhasabuilt‐inUSBportforusewiththeManometerDataAcquisitionsoftware.The
softwareallowstheusertoview,save,export,andprintreadingsfromtheHD755.Refertothe
documentationincludedwiththesoftwareforcompletedetails.
DisplayedErrorCodes
Thefollowingcodesaredisplayedwhenthemeterencountersanerror.
ERR1:Pressureinputexceedsspecifiedlimits
ERR2:Pressureinputistoolowtoread
ERR3:TheDifferentialPressureinputexceedsspecifiedlimits
ERR4:TheDifferentialPressureinputistoolowtoread

HD755-EU-EN V1.7 7/13
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Specifications
GeneralSpecifications
DisplayFourdigitLCDwithfunctionindicators
UnitsofMeasureBAR,mBAR,psi,kg/cm2,mmHg,inchesHg,kPa,feetH2O,inches
H2O,cmH2O,andozin2
Accuracy±0.3%FS+1d(@25°C)
Repeatability±0.2%to0.5%FS
Linearity/Hysteresis±0.3%FS
CombinedAccuracy±1.1%FS
MaximumPressure2psi
Responsetime0.5stypical
InputcircuitDifferentialinputs(P1andP2)
InputPortsTwometal4.8mm,barbedfor1/8"(3.17mm)IDtubing
DataHoldFreezesdisplayedreading
SensorBuilt‐inpiezoelectricsensors
Zero/OffsetfunctionPushbuttonactivation
Samplerate0.5sec.(approx.)
CompatibilityAirornon‐corrosiveandnon‐ionizedgas(notintendedforusewith
liquids)
AutoPowerOFFMeterturnsoffafterapprox.20minutestoconserveenergy(can
bedeactivated)
PCInterfaceBuilt‐inUSBserialinterface
Storageconditions0to60oC(14to140oF);<80%RH
Operatingconditions0to50oC(32to122oF);<80%RH
Batterypower9Valkalinebattery(BATlowbatteryindicator)
Batterylife125hourstypical
Dimensions210x75x50mm(8.2x2.9x1.9”)
Weight280g(9.8oz)

HD755-EU-EN V1.7 7/13
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RangeSpecifications
Range/Units(Max.)Resolution
±0.034bar0.001
±34.47mbar0.01
±0.500psi0.001
±0.035Kg/cm20.001
±25.86mmHg0.01
±1.018inchesHg0.001
±3.447kPa0.001
±1.154feetH2O0.001
±13.85inchesH2O0.01
±35.15cmH2O0.01
±8.00ozin20.01
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BatteryReplacement
WhenthelowbatteryindicatorBATappearsonthedisplayorifthemeterdoesnotswitchon
whenthePOWERbuttonispressed,itisnecessarytoreplacethebattery.
Toreplacethebattery:
1. Openthebatterycompartmentbyslidingthemeter’srearpanelinthedirectionofthe
embossedarrow.
2. Replacethe9Valkalinebattery
3. Replacethebatterycompartmentcover.
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AllEUusersarelegallyboundbytheBatteryOrdinancetoreturnallusedbatteriesto
communitycollectionpointsorwhereverbatteries/accumulatorsaresold.
Disposalinhouseholdtrashorrefuseisprohibited.
Disposal:Followthevalidlegalstipulationsinrespectofthedisposalofthedeviceatthe
endofitslifecycle
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OtherBatterySafetyReminders
Neverdisposeofbatteriesinafire.Batteriesmayexplodeorleak.
Nevermixbatterytypes.Alwaysinstallnewbatteriesofthesametype.
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Warning: Pressure inputs of 10 psi or higher will damage the instrument. Do not
apply pressure higher than the maximum pressure listed in the specification table

HD755-EU-EN V1.7 7/13
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Conversions
UsefulconversionFactors
FromToMultiplier
inofH2OinofHg0.07355
inofH2OcmofH2O2.54
mmofHginofH2O0.03937
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Copyright©2013FLIRSystems,Inc.
Allrightsreservedincludingtherightofreproductioninwholeorinpartinanyform
ISO‐9001Certified
www.extech.com
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