PHS25 pH计说明书.docx
《PHS25 pH计说明书.docx》由会员分享,可在线阅读,更多相关《PHS25 pH计说明书.docx(6页珍藏版)》请在冰豆网上搜索。
PHS25pH计说明书
PHS-25PHMETER
OPERATIONMANUAL
CATALOGUE
ⅠBriefIntroduction…………………………………………1
ⅡWorkingPrinciple…………………………………………1
ⅢMainSpecification…………………………………………1
ⅣPanelLayout………………………………………………2
ⅤUsage…………………………………………………………2
ⅥAnalyticalMethod…………………………………………3
ⅦFaultyandRemoval…………………………………………3
ⅧTransportationandStorage………………………………3
ⅨNotes…………………………………………………………4
ⅩTable1………………………………………………………4
ⅪComponentsofDevice…………………………………………4
ⅠBriefIntroduction
AsystemofaglasspHelectrodeandacalomelelectrodehasdifferentdirectpotentialresponsetodifferentacidityinmeasuredsolution.ModelPHS-25pHmeterisaportableanalyzerwith31/2digitalLCDdisplay.Itiswidelyusedinmedicalsanitation,environmentalprotection,agriculture,minefield,teachingandresearchetc.TomeasurepHvalueandpotential(mV)ofwatersolution.
ⅡWorkingprinciple
ModelPHS-25pHmeterworksbasedonthisprinciple.ThatresponseisinputintoadirectcurrentamplifierwhichiswithhighinputimpedanceanddeepnegativefeedbacktomeasurethepHvalueofthesolution.
AglasspHelectrode,acalomelelectrodeandthemeasuredaqueoussolutioncomposeameasuringcell.TherelationshipbetweencellelectromotanceandsolutionpHvalueaccordswithNernst,sEquation:
RT
E=Eo-2.30----pH
F
Where
R,standsforconstant(unit:
8.314J/K.mol);
T,absolutetemperatureofsolution;
F,Faradayconstant(unit:
9.65×104C/mol);
E0,theinterceptpotentialoftheelectrodesystem,whichcanbeasaconstantundercertaincondition;
pH,thepHvalueofthemeasuredsolution.
E,cellpotentialproducedbyelectrodesystem.
ⅢMainSpecification
Range:
pH0.0to14.0pH/mV0to±1999mV
Accuracy:
pH0.1pH±1digit/mV4mV±1digit
Resolution:
pH0.1pH/mV4mV
Inputresistanceofelectron:
>5×1011Ω
Inputcurrentofelectronunit:
≤1×10-11A
Rangeoftemperaturecompensation:
0to60℃
Pointofzeropotential:
7.0pH
Workingcondition:
Temperature:
0to40℃Humidity:
≤80%RH
Dimension:
64×185×160mm3
Weight:
600g
Powersupply:
AC220V±22V50HzDC5V(transistorcells)
ⅣPanelLayout
1.LCDdisplaywith31/2digiì¥Á9ðR¿3
bjbjýÏýÏ2RŸ¥Ÿ¥ˆÿÿÿÿÿÿl^^
2.^^^^^rŒ
Œ
Œ
Œ
$°
4r?
&.ð
3.ð
ð
ð
ð
ð
ð
4.ð
%%%%%
5.%%$¾'Þ)X9%^ð
ð
ðð
ð
9%ü^^ð
ð
6.J&üüüð
^ð
^ð
7.%üð
%üîüêÆ_#?
^^%ð
ä
À5˃Âr
Œ
þ
šï#
8.%`&0?
&$6*˜d6*%ürr^^^^ÙꗬÁ‹Љ勰¿ကЀ㌁
橢橢쿽쿽ࠄ刲ꖟꖟẈlŞŞŞŞŞŞ
Ş
1.Ųಌಌಌಌ$ರ4Ų⚐
a.┓┕┕┕┕┕┕$➾Ƞ⧞X┹đŞ┹rodeoralonguseless.
b.ThispHmetermakesusesofone-pointlocation.Toensuredetectingprecision,selectastandardbuffersolutionwhosepHvalueapproachesthemeasuredsample.Itisexpectedthatthedifferencedoesnotextend3pH.(ⅰ.E.,|pHstandard-pHsolution|<3pH).
2.Measurementofelectrodepotential(mV)
a.PutthedialbuttoninmVposition.Donotinserttheelectrode.Adjust“Zeroadjust”knobandthedevicedisplays“Zero”.
b.Contacttheelectrodesandputtheminthemeasuredsolution.Thedisplayvalueistheelectrodepotential(mV)aftertheresponseisconstant.
3.MeasurementofpHvalue:
a.Putthebuttonin“pH”position.Adjustthetemperaturecompensationknobaccordingtothetemperatureofthesolution.ContacttheelectrodeandinsertthemintothestandardpHbuffersolution.Adjust“Location”knobtomakedisplaythepHvalueofthestandardbuffersolutionatthistemperature.Thenthestandardizationiscompleted.
b.Removetheelectrodeandfluxwithdistilledwater.Absorbthesurfacewaterwiththefilterpaperandsettheminthemeasuredsolution.ThedisplayispHvalueofthemeasuredsampleaftertheresponseisconstant.
ⅥAnalyticalMethod
1.Preparationofbuffersolution:
Dissolvethe6.86standardbufferreagentin250mlvolumetricflaskwithdistilledwater.Theneededstandardbuffersolution(pH=6.86)canbeget.
2.Example:
DetectpHvalueoftheriverwater(Itstemperatureis19℃).
Theselectedelectrodearemodel231glasselectrodeandmodel802(or232)referenceelectrode.
Themeasuringperiodisasfollowing:
a.Putthebuttonin“mV”positionandadjustzeropoint.
b.Putthebuttonin“pH”positionandthe“Temperaturecompensation”in“19”.Puttheactivatedcleanmodel231pHglasselectrodeandmodel802saturatedcalomelelectrodeinthestandardbuffersolutionofpH=6.88.InsertpHelectrodeintothe“measuringelectrode”positionandmodel802calomelelectrodethe“ReferenceElectrode”contact.Atthistime,thedevicegivesadisplay(anarbitrarypHvalue).Adjustthe“Location”knobtomakethedisplay6.88pH.Thenlocationiscompleted.
c.Removetheelectrodeout.Putthecleanedelectrodesintotheriverwater.ItsconstantdisplayispHvalueoftheriverwater.Thenthemeasurementiscompleted.
ⅦFaultyandRemoval
1.Whentheelectrodedonotcontactwiththesolutionorthemeasureisinover-range,thedisplayis□□□□□togiveanalarm.
2.Donotinterfacetheelectrodeandputthebuttonin“pH”position.Ifthecalibrationscopeis7pHbelow,thecellsshouldbereplaced.
3.Inthepropervoltageforthecells,makethelocationinstandardpHsolution.IfitcannotbeadjustedtothestandardpH,theelectrodesshouldbereplacedowingtothenonparallelofthezeropotentialpointfortheelectrodesandthedevice.Turnonanewdeviceandthedisplayisnotgiven,thenthecellsshouldberefixed.
ⅧTransportationandStorage
1.Transportation:
Theinstrumentcanbetransportedbygeneraltraffictoolwithoutstrongstrike,heavyandexposuretothesun.
2.Storage:
theinstrumentshouldbestoredinthestoreroomwithenvironmentaltemperature0℃to40℃andhumiditynomorethan85%.Thereshouldbenocorrosivegasandchemicalreagentsinthestoreroom.Whilenotinuseforalongtime,theinstrumentshouldbecoveredwithdustcoatandsetinventilationanddryplace.
ⅨNotes
1.Whenadjustingzero,theQ9shortcircuitplugshouldbeputon.Whenmeasuringandcalibration,theQ9plugshouldbeputdownandthemeasuringelectrodeputon.
2.Whilenotinuseforalongtime,theinstrumentshouldbechargedononceeverymonthforthechargingcell,slife.
3.Whilechargingin“OFF”position,thechargingtimeshouldlessthanthreehourseverytime.Whenusinginternalchargingcells,theinstrumentshouldbechargedonaftersixhoursusing.
ⅩTable1
Threekindsofstandardbuffersolution,spHvalueunderdifferenttemperature
ⅪComponentsofdevice
1.Equipment1set
2.Model231glasselectrode1pc
3.Model232(or802)calomelelectrode1pc
4.Buffersubstance(ph=4,7,9)1pair
5.Polyethylenebottle1pcs
6.Chargepower1pc
7.Plasticsscrewdriver1pc
8.Operationmanual1pc