Operation Manual

Automatic Titrator

TIT-8

PLEASE READ THIS MANUAL CAREFULLY BEFORE OPERATION

3, Hagavish st. Israel 58817 Tel: 972 3 5595252, Fax: 972 3 5594529 mrc@mrclab.com

MRC.12.15

ContentsContentsContentsContents

I.Introduction ……………………………………………………………… 1

II. Technical specifications and performance……………………………3

III.Functions of the instrument……………………………………………4

IV. Operation ………………………………………………………………6

V. The use of the electrodes and maintenance ………………………34

VI. Maintenance and service of the instrument ………………………35

VII. Supporting instrument………………………………………………38

VIII. Appendix…………………………………………………………….38

Warning: The instrument can not provide the designed

protection for operators who do not follow the right procedures andrequirements given by the manufacturer.

Warning: All solutions must be handled with care according to

the lab’s safety regulation. Please make a reference to the relatedmaterial safety data sheet. Wear the lab-gown, goggle and rubbergloves all the time. Be care of hot reagents.

Warning: Be aware of the risk of electric shock. Only the

trained professionals are permitted to open the face panel or backcover.

- 1 -

I.I.I.I. IntroductionIntroductionIntroductionIntroduction

TIT-8 Automatic Titrator is a high precision and high performance laboratory analyzer with comprehensive functions, which can be used in food production, medicine inspection, petroleum and chemical industries, metallurgy, education and scientific research and so on.1.1.1.1. FeaturesFeaturesFeaturesFeatures：a. Adopting the modular design technology, the instrument consists ofthe control unit, volume titration unit and pH/mV measuring Unit.b. With touch screen, e-v titrating curve, first-order derivative andgraphing contrast analysis are instantly displayed. Titration mode canbe compiled and amended.c. With menus, graphs and shortcut keys etc, the operation interfacewritten in English is user–friendly. Benefitting from the auto power-offprotection, all data and parameters can be saved even if unusualelectricity cutting off happens.d. With different electrodes, the following experiments can be carriedout: the acid-base titration, oxidation-reduction titration,complexometric titration, precipitation titration and non-aqueoustitration and measurement of pH values.e. It can be connected with micro thermal printer, print the measureddata and titration curvef. There are five titration modes including macro titration, micro titration,end point setting titration, volume setting titration and mode titration.g. The transmission system has been designed accurately to reducethe operation noise effectively. The stirring system can control speedindependently, so it can be used as an agitator.2.2.2.2. OperatingOperatingOperatingOperating fffflowlowlowlow ccccharthartharthart (just(just(just(just forforforfor reference)reference)reference)reference)

- 2 -

Start up

Fluid infusion

Set up

Fluid infusion

Yes

Accurate pHvalue

Yes

Store or printtitration data

Cleaning（at least 6 times）

Titration(chose the suitable mode)

Chose the suitable electrode

Calibration electrodeNO

NO

- 3 -

IIIIIIII.... TechnicalTechnicalTechnicalTechnical specificationsspecificationsspecificationsspecifications andandandand performanceperformanceperformanceperformance

2.1.2.1.2.1.2.1. MeasurementMeasurementMeasurementMeasurement range:range:range:range:pH：（0.00～14.00）pH；mV：（-1999.0～1999.0）mV；Temperature：（0.0～100.0）°C.2.2.2.2.2.2.2.2. ResolutionResolutionResolutionResolution：pH ：0.01pH；mV：0.1mV；Temperature: 0.1°C.2.3.2.3.2.3.2.3. ElectronicElectronicElectronicElectronic unitunitunitunit accuracy:accuracy:accuracy:accuracy:pH ：±0.01pH ±1 bit ；

mV：±0.2mV±1 bit ；

Temperature: ±0.3°C±1 bit;Sensitivity of controlling titration: ±2mV.2.4.2.4.2.4.2.4. RepeatabilityRepeatabilityRepeatabilityRepeatability ofofofof titrationtitrationtitrationtitration analysis:analysis:analysis:analysis: 0.2%.0.2%.0.2%.0.2%.2.5.2.5.2.5.2.5. ElectronicElectronicElectronicElectronic unitunitunitunit repeatability:repeatability:repeatability:repeatability: ≤≤≤≤0.2mV.0.2mV.0.2mV.0.2mV.2.6.2.6.2.6.2.6. ElectronicElectronicElectronicElectronic unitunitunitunit stability:stability:stability:stability: ±±±±0.3mV0.3mV0.3mV0.3mV±±±±1111 bit/3h.bit/3h.bit/3h.bit/3h.2.7.2.7.2.7.2.7. NormalNormalNormalNormal operatingoperatingoperatingoperating conditions:conditions:conditions:conditions:a) ambient temperature: （5.0～35.0）°C；b) relative humidity: ≤80%;c) power supply: (100--240）V；frequency:（50/60）Hz；d) Without disturbing by electron magnetic field except terrestrialmagnetic field.

- 4 -

III.... FunctionsFunctionsFunctionsFunctions ofofofof thethethethe instrumentinstrumentinstrumentinstrument

The main titration modes of the instrument contain macro titration,micro titration, end point setting titration, volume setting titration andmode titration. Different electrodes can be fitted with the instrument todo different titration, such as: acid-base titration, oxidation-reductiontitration, complexometric titration, precipitation titration, non-watertitration and permanent pH measuring etc (showed in Table 1).Different titration type choose different titrant (several common titrantis showed in Table 2). It will alarm when the instrument find the endpoint of titration in the process.

Warning：1.Please read this manual carefully before use theinstrument.2. The shelf life of all electrodes is one year, after sales forone year, whether it is used or not, the performance will beaffected, it should be replaced.3.When users are doing titration test, especially strongcorrosive solution like: strong acid, strong base, perchloricacid etc. You should pay attention to protection, had bettertake mask and gloves, in case of the harm to human body！

- 5 -

TableTableTableTable 1111 Selected electrode in several common titration

Experiment Title Selected electrode

Acid-basetitration

pH glass electrode,calomel reference

electrodecombined pHelectrode

Oxidation-reduction titration

platinum electrodecalomel reference

electrodePrecipitationtitration

silver electrodedouble salt bridgecalomel electrode

complexometrictitration

platinum electrodecalomel reference

electrodeNon-watertitration

pH glass electrode,calomel reference

electrode

- 6 -

TableTableTableTable 2222 Selected titrant in several common titration

Experiment Title Selected titrant

Oxidation-reductiontitration

Oxidation reaction（potassium dichromate）

Reduction reaction（sodium thiosulfate）

acid-base titration HCl or NaOH

Precipitation titration(Cl)(Cl)(Cl)(Cl) silver nitrate

Titration silver ion sodium chloride solution

Complexometric titration EDTA standard solution

Non-water titration perchloric acid standardsolution（Note：glacial acetic acid assolvent）

IV.IV.IV.IV. OperationOperationOperationOperation

4.1.4.1.4.1.4.1. SwitchSwitchSwitchSwitch onononon thethethethe InstrumentInstrumentInstrumentInstrument

Switch on the instrument and it will show the initial interface (Figure 1):

- 7 -

Figure 1The instrument shows menu on the top of screen which including 'Stir','Self-test', 'Setup', 'View', 'Calibration' etc. In the middle is the pressbutton in common use including 'Fluid infusion', 'Clean' and 'Titration'.It displays the current time, potential value (or pH value) andtemperature at the bottom. User can enter the corresponding functionpanel by pressing the button.4.2.4.2.4.2.4.2. FluidFluidFluidFluid infusioninfusioninfusioninfusionIn the initial interface, press 'FluidFluidFluidFluid infusioninfusioninfusioninfusion', to enter FluidFluidFluidFluid infusioninfusioninfusioninfusioninterface. The instrument displays as follows:

Figure 2.1Press 'ConfirmConfirmConfirmConfirm', the instrument starts to infuse solution, meanwhile

- 8 -

'state' shows 'Fluid'Fluid'Fluid'Fluid infusinginfusinginfusinginfusing', it displays as follows:

Figure 2.2When infusing finished, status will display 'FFFFluidluidluidluid infusioninfusioninfusioninfusion completedcompletedcompletedcompleted',Press 'BackBackBackBack', return to main menu. In the process of infusing, user canterminate infusing by pressing 'StopStopStopStop', status will display 'StopStopStopStop fluidfluidfluidfluidinfusioninfusioninfusioninfusion'.4.3.4.3.4.3.4.3. CleaningCleaningCleaningCleaningWe suggest that using standard liquid cleaning more than 6 times.In initial interface, press 'Clean''Clean''Clean''Clean' button, instrument displays as follows.

Figure 3User can set cleaning cycles number at mostly 9 times. When settingfinished, press 'StartStartStartStart' button to start clean, meanwhile ''''CleaningCleaningCleaningCleaning''''

- 9 -

shows the cycles number. After finished, it returns back to originalstate,as well, user can stop it at any time in the process of cleaning.4.4.4.4.4.4.4.4. TitrationTitrationTitrationTitrationThe instrument provides 5 kinds of titration modes: macro titration,micro titration, end point setting titration, volume setting titration, modetitration.In initial interface, press 'Titrat'Titrat'Titrat'Titrationionionion'''', instrument shows all titrationmodes, user can select needed titration mode for correspondingtitration, shown as follows:

Figure 4Macro titration: This mode is one of the main titration modes, whenusers test an unknown sample, they can find titration end-pointautomatically through macro titration, and setup in mode titration, thengenerate special titration mode.Micro titration: This mode is suitable for the titration which demandsless titrant (below 1mL). In this mode, every time the instrument addsat least 0.002 mL of volume (users can amend this parameter asrequired).End point setting titration: If users know the titration end point value ofpotential, end point setting titration function is available. Input endpoint number, end point jump value or potential value and end pointpre-control range (pre-control point is transferring point from high

- 10 -

speed titration to low speed titration), you can begin titration.Volume setting titration: In this mode, user can set the next volume ofadding at any time according to the process of titration.Mode titration: when users know the titration parameter, specialtitration mode is thus generated in the mode. Titration can be donelater only if this mode is chosen.4.4.1.4.4.1.4.4.1.4.4.1. MacroMacroMacroMacro titrationtitrationtitrationtitrationMacro titration is one of the main titration modes, when users test anunknown sample, they can find titration end-point automaticallythrough macro titration, and setup in mode titration, then generatespecial titration mode.In initial interface, press 'Titrat'Titrat'Titrat'Titrationionionion'''', instrument shows all titrationmodes, users select ''''mmmmacroacroacroacro titration'titration'titration'titration', instrument enters into macrotitration, shown as follows:

Figure 4.1.1Before macro titration mode, users need to set some parameters. Theparameter including: mV/pH titration parameter, minimum addingvolume parameter, initial adding volume parameter, number of endpoint parameter, end point jump value parameter and end volumeparameter. This part of parameter controls macro titration mode of theinstrument, amending of it will influence the result of macro titration. Inthe most situations, it is unnecessary for users to amend this part of

- 11 -

parameter: the titration demand will be satisfied.4.4.1.14.4.1.14.4.1.14.4.1.1 mV/pHmV/pHmV/pHmV/pH ttttitrationitrationitrationitration pppparameterarameterarameterarametermV/pH titration parameter is used to indicate the titration is mV titrationor pH titration. When users select mV titration, the current titration ismV titration, all displayed parameter are according to mV and viceversa.4.4.1.24.4.1.24.4.1.24.4.1.2 NumberNumberNumberNumber ofofofof endendendend pointpointpointpointUsers can set the number of end point according to the actual titrationreaction. In order to satisfy the requirement of multi-end point titration,the instrument allows five end points at most in any titration. There arefive independent controlled values corresponding to five end points.The controlled value can be set to be large or small independently. It isimpossible that various titration to have the united mode or method.4.4.1.34.4.1.34.4.1.34.4.1.3 EndEndEndEnd pointpointpointpoint jumpjumpjumpjump valuevaluevaluevalueEnd point jump value is the final basis for instrument to judge the endpoint. In this option, set the end point jump value corresponding to thenumber of end point. If user observes that end point jump value oftitration is somewhat low or noise is too large, with the result thattitration end point is difficult to find, we suggest that user reset this partof parameter (set end point jump value to a smaller one if end pointjump is low, and set end point jump value to a larger one if noise islarge, generally we suggest to set for 1000). Click the blank area ofend point jump value, input jump value after numeric keypad appeared,user can set according to this method in later setup.

- 12 -

Figure 4.1.24.4.1.44.4.1.44.4.1.44.4.1.4 MinimumMinimumMinimumMinimum addingaddingaddingadding volumevolumevolumevolumeUser is allowed to set minimal adding volume, usually is 0.005mL,minimum volume is 0.002mL. The setting method is the same as endpoint jump value.4.4.1.54.4.1.54.4.1.54.4.1.5 InitialInitialInitialInitial addingaddingaddingadding volumevolumevolumevolumeWhen the titration volume is larger, user can set initial adding volumein accordance with specific conditions, then the instrument will adjustthe adding volume automatically according to the process of titration,thus speed up the rate of titration.4.4.1.64.4.1.64.4.1.64.4.1.6 EndEndEndEnd volumevolumevolumevolumeWhile macro titration, if a titration end point is found, the instrument willautomatically search for the next end point, in the meantime, titrationdoes not stop, Press "ExitExitExitExit" button or according to end volume setupvalue, titration will stop. End volume default is 10mL, user can reset itaccording to actual requirement. When adding volume reaches touser's set end volume, instrument will stop titration automatically. Ifuser needs to amend some parameter, please select a certainparameter and instrument will jump out a key-in window, inputnecessary corresponding data is fine.Reminder: All these parameter control the whole titration directly andany amendment of parameter will influence the final titration results.

- 13 -

So please understand all these parameter before amendment.If the parameters input is incomplete in Figure 4.4.1. The instrumentcan not titrate. Shown as follows:

Figure 4.1.3After all parameters setting finished, press ''''ConfirmConfirmConfirmConfirm'''' to start macrotitration. Then instrument will switch on the stirrer automatically andstir for 10s. User can adjust stirring speed，increase or reduce it. Thespeed which has been set will be saved automatically, the next timeyou switch on the stirrer, it will stir according to the speed which hasbeen set last time. Shown as follows:

Figure 4.1.4Instrument will control the whole process of titration according to

- 14 -

macro titration mode and no need to interfere. Automatic adding,automatic judgment, automatic sampling, automatic judge end point,displaying dynamic state of titration curve and titration data whileadding will be done by instrument. Instrument will chirp for once toremind user when finds all end points. Instrument will not stop when itfinds one end point, it will go on titration to find next end point. After allend points are found, it will appear ''''End point search completed, exitor not''''.... Press ''''ConfirmConfirmConfirmConfirm'''' button to end titration, press 'Cancel''Cancel''Cancel''Cancel' buttonto continue. Display as follows:

Figure 4.1.5If users consider all end points are found, he can press 'E'E'E'Exitxitxitxit'''' button toterminate titration and instrument will display 'Exit or not?' to reconfirmwhether user really want to end titration. User can terminate or go ontitration according to actual need. When titration volume is end volumewhich has been set (max volume), it will remind user whether tocontinue and user can select end titration or go on titration accordingto actual need. Press 'ConfirmConfirmConfirmConfirm' button to end titration, press 'CancelCancelCancelCancel'button to continue. Display as follows:

- 15 -

Figure 4.1.6Note: the instrument allows five end points at most in any titration. Ifuser set the number of titration end point is five, then the instrumentfinds that 5 end points have been found, it will stop titration directly nomatter whether the titration has other end points or not.After titration finished, display as follows:

Figure 4.1.7It shows the current potential (or pH) value and current titration volume.When titration finished, user can press to see real-timepotential value and titration volume corresponding to each titrationpoint on the titration curve, users can check end point potential valueand titration volume by pressing 'End'End'End'End point'point'point'point'.... In the figure above, the

- 16 -

blue line is titration curve, red line is first-order derivativecorresponding to titration curve.Press 'Save''Save''Save''Save',,,, display as follows: Data saved success. See Figure4.1.8.

Figure 4.1.8The instrument allows users store up to 40 analysis results, when allthe results are saved, it will prompt as below, shown as Figure 4.4.9. Atthis moment users should get back to menu ''''ViewViewViewView'''', delete someneedless analysis results, then you can continue to save titrationresults. If not, you could not save the later date.

Figure 4.1.9

- 17 -

4.4.2.4.4.2.4.4.2.4.4.2. MMMMicroicroicroicro titrationtitrationtitrationtitrationMicro titration mode is suitable for the titration that demands less titrant(below 1mL). In this mode, every time the instrument adds at least0.002mL of volume (users can amend this parameter as required).Select ''''MMMMicroicroicroicro titrationtitrationtitrationtitration'''' in ''''TitrationTitrationTitrationTitration'''' item, shown as follows:

Figure 4.2In micro titration mode, setting method of some parameters are thesame as macro titration mode. User can set the parameter as in macrotitration mode, the difference is the set of each adding volume.EEEEachachachach addingaddingaddingadding volumevolumevolumevolumeAfter the parameter setting finished, every time the instrument addsfixed volume according to the pre-set parameter. The minimum volumeshould be 0.002mL.4.4.34.4.34.4.34.4.3 EEEEndndndnd pointpointpointpoint settingsettingsettingsetting titrationtitrationtitrationtitrationIf users know the titration end point value of potential, end point settingtitration function is available. Input end point number, end point jumpvalue or potential value and end point pre-control range (pre-controlpoint is transferring point from high speed titration to low speedtitration), you can begin titration.In 'Titration''Titration''Titration''Titration' interface, select '''' EndEndEndEnd pointpointpointpoint settingsettingsettingsetting titrationtitrationtitrationtitration ''''，shown asfollows:

- 18 -

Figure 4.3Before end point setting titration mode, user needs to set someparameters. The parameter including: mV/pH titration parameter, endpoint number parameter, pre-control range parameter correspondingto each end point, end point parameter.4.4.3.14.4.3.14.4.3.14.4.3.1 mV/pHmV/pHmV/pHmV/pH ttttitrationitrationitrationitration pppparameterarameterarameterarameterIt is the same as mV/pH titration parameter in macro titration mode.4.4.3.24.4.3.24.4.3.24.4.3.2 EEEEndndndnd pointpointpointpoint numbernumbernumbernumber parameterparameterparameterparameterThe same as end point number parameter in macro titration mode.4.4.3.34.4.3.34.4.3.34.4.3.3 EndEndEndEnd pointpointpointpoint ppppre-controlre-controlre-controlre-control rangerangerangerange parameterparameterparameterparameterPre-control range parameter tells user titration end point is coming andthe instrument need to slow down the adding speed. The setting of thisvalue will directly influence the correction of final result and actualtitration time. If pre-control range is set close to end point, when itreached pre-control range, the result will be incorrect caused by thespeed of titration too fast. If pre-control range is set too far from endpoint, the total titration time will be increased. Also pre-control pointshould be set before end point. Otherwise the pre-control point will beinvalid. The principle for setting pre-control range is: to the reaction oflarge jump, pre-control point should be set far from end point potential(usually more than 100mV from end point potential). And to thereaction of small jump, pre-control point could be set close to end point

- 19 -

to quicken the speed of titration.4.4.3.44.4.3.44.4.3.44.4.3.4 EndEndEndEnd pointpointpointpoint parameterparameterparameterparameterEnd point parameter is the known titration end point and just need toinput. User can switch from different end point jump value by pressingthe arrow key on the right of end point.Setting method of minimum and initial adding volume parameter is thesame as macro titration.After setting all above parameters correctly, press ''''ConfirmConfirmConfirmConfirm'''' button tostart end point setting titration. Also when set above parameter, usercan set stirrer speed or calibrating electrode slope.4.4.44.4.44.4.44.4.4 VolumeVolumeVolumeVolume settingsettingsettingsetting titrationtitrationtitrationtitrationIn this mode, user can set next volume of adding at any time accordingto the process of titration.In initial interface, press ''''TitrationTitrationTitrationTitration'''',,,, select ''''VolumeVolumeVolumeVolume settingsettingsettingsetting titrationtitrationtitrationtitration'''',,,,shown as follows:

Figure 4.4.14.4.4.14.4.4.14.4.4.14.4.4.1 mV/pHmV/pHmV/pHmV/pH titrationtitrationtitrationtitration parameterparameterparameterparameterThe same as mV/pH titration parameter in macro titration mode.4.4.4.24.4.4.24.4.4.24.4.4.2 NumberNumberNumberNumber ofofofof endendendend pointpointpointpointThe same as end point number titration parameter in macro titrationmode.4.4.4.34.4.4.34.4.4.34.4.4.3 EndEndEndEnd volumevolumevolumevolume

- 20 -

The same as end volume titration parameter in macro titration mode.4.4.4.44.4.4.44.4.4.44.4.4.4 EndEndEndEnd pointpointpointpoint jumpjumpjumpjump valuevaluevaluevalueThe same as end point jump value titration parameter in macro titrationmode.4.4.4.54.4.4.54.4.4.54.4.4.5 InitialInitialInitialInitial addingaddingaddingadding volumevolumevolumevolumeThe same as initial adding volume titration parameter in macro titrationmode.After setting all above parameters correctly, press ''''ConfirmConfirmConfirmConfirm''''button to start titration. In the process of titration, user can set actualtitration volume manually, shown as follows:

Figure 4.4.2In this interface, users can change the adding volume as your requireby pressing arrow key at the top right corner in the process of titration,so that quicken the rate of titration.4.4.54.4.54.4.54.4.5 ModeModeModeMode titrationtitrationtitrationtitrationWhen users know the titration parameter, special titration mode can bethus generated, and edit the name of titration mode. Titration can bedone later only if this mode is chosen.Mode titration is for a particular titration and its end point is known; or itis a special mode generated by user when you are satisfied with theresult after macro titration for convenience of next reusing.In initial interface, press ''''TitrationTitrationTitrationTitration'''', select ''''modemodemodemode titrationtitrationtitrationtitration'''', shown asfollows:

- 21 -

Figure 4.5.14.5.14.5.14.5.14.5.1 NewNewNewNew modemodemodemodeAfter macro titration, user can get certain parameter. Then input someparameters including: titration mode name, end point number, initialadding volume, minimum adding volume and end point pre-controlrange in this new mode. Press ''''ConfirmConfirmConfirmConfirm'''', a new titration mode will begenerated.

Figure 4.5.2Press the blank area of ''''titrationtitrationtitrationtitration modemodemodemode namenamenamename'''', displayed as follows:User can edit or input titration mode name in this interface.

- 22 -

Figure 4.5.34.5.24.5.24.5.24.5.2 DeleteDeleteDeleteDelete modemodemodemodeIf users built a new titration mode, some parameters may be found toneed to be modified, now you should delete the before mode, andbuild a new one. If users find this mode is useless, you could delete itby pressing 'Delete'Delete'Delete'Delete mode'mode'mode'mode'....4.5.34.5.34.5.34.5.3 NumberNumberNumberNumber ofofofof endendendend pointpointpointpointThe same as end point number titration parameter in macro titration.4.5.44.5.44.5.44.5.4 InitialInitialInitialInitial addingaddingaddingadding volumevolumevolumevolumeThe same as initial adding volume titration parameter in macrotitration.4.5.54.5.54.5.54.5.5 EndEndEndEnd pointpointpointpoint ppppre-controlre-controlre-controlre-control rangerangerangerangeThe same as end point pre-control range titration parameter in macrotitration.4.5.64.5.64.5.64.5.6 TitrationTitrationTitrationTitration modemodemodemodeSetting method is the same as mV/pH titration parameter in macrotitration mode, users can select by pressing blank area in titrationmode.4.5.74.5.74.5.74.5.7 EndEndEndEnd pointpointpointpointSetting method is the same as end point jump value in macro titrationmode, users can press blank area directly, to input end point jumpvalue in keyboard.

- 23 -

5、StirringTIT-8 contains an independent magnetic stirring stand, press 'Stir' in initial interface, it can be stirred fully before titration or stirred separately in the preparation of test solution.On the magnetic stirring stand, you can adjust the stirring speed directly by pressing '++++ ––––', it is simple and convenient. The stirring speed which you have set at last time will be saved automatically, when we turn on the instrument it will carry out the stirring speed that you have set at last time.6666、SSSSeeeellllf-f-f-f-tteteteessssttttIn initial interface, click ''''sssseeeellllffff----tetetetesssstttt'''' to enter this interface, shown a s below:

Figure 6.1The self-test interface including: stirring system, push sample testing, electromagnetic valve.Press ''''stirringstirringstirringstirring system'system'system'system', if it works normally, that means the agitator isnormal. If not, you should check the line connection is in goodcondition or not.Push sample testing: this function is to check the burette titration isnormal or not. Press ''''pushpushpushpush samplesamplesamplesample testingtestingtestingtesting'''', the end of burette whichis connected to titration cup will carry on the titration. If there is fault, itwill appear ''''GratingGratingGratingGrating encoderencoderencoderencoder fafafafaultultultult'''', displayed as figure 6.2:

- 24 -

The user should check power connection timely or contact our salesservice, we will solve the problem as soon as possible.

Figure 6.2Electromagnetic valve is to check the 3-way valve which is connectedto burette is work normally or not. Press 'electromagnetic'electromagnetic'electromagnetic'electromagnetic valve'valve'valve'valve', youwill hear the sound, that means it works normally.7.7.7.7. SetupSetupSetupSetupThe system parameter includes: electrode potential, burette coefficient,and time,,,, Displayed as follows:

Figure 7.1

- 25 -

7.17.17.17.1 ElectrodeElectrodeElectrodeElectrode potentialpotentialpotentialpotentialIn the process of titration, we can set equilibrium potential value andthe balance of potential time, click the 'electrode'electrode'electrode'electrode potential'potential'potential'potential' in theinterface, shown as below:

Figure 7.27.1.17.1.17.1.17.1.1 BalanceBalanceBalanceBalance potentialpotentialpotentialpotential parametersparametersparametersparametersTitration process as follow: First of all, it will add a certain amount oftitration solution, after that, it will collect the potential valueautomatically, then calculate the next adding quantity according to thepotential changes. Repeat adding, collecting, calculation until thetitration is over. The potential of the collect is very important, becausewhen titration agent is added, the instrument will collect the potential ofadding to calculation the next adding quantity. It allows user to set upbalance range of potential, that is, the potential range change. Whenstart titration, the instrument will automatically judgment and collectingcurrent potential, if the changes of current potential could meet thebalance potential conditions that user set, the potential is effective,otherwise the instrument will waiting for the changes until it meet therequirements (It allows users to set the minimum balance potentialvalue for 0.5 mV, maximum for10.0 mV). The default value of thebalance potential is 1.0 mV.

- 26 -

7.1.27.1.27.1.27.1.2 EquilibriumEquilibriumEquilibriumEquilibrium timetimetimetime parametersparametersparametersparametersThe same as the balance potential parameters, equilibrium timeparameter is used to control the potential collecting of the titrationagent, when the change of the potential is bigger, and the potential stillcannot satisfy the equilibrium conditions, it is necessary to limit thetime parameter, otherwise the instrument will going on waiting forpotential balance. It allows users to set equilibrium time, that is, ifpotential still cannot get balance, when it reaches balance time thatthe users set, the system will still continue to titration so the potentialfirst meet balance potential conditions, the equilibrium time conditionswill be failure (instrument allows users to set the minimum balancetime for 2 s, maximum for 9 s). The default value of equilibrium time is4 s.7.27.27.27.2 BuretteBuretteBuretteBurette coefficientcoefficientcoefficientcoefficientBurette coefficient is used for adjusting scale error of burette. Click the'burette'burette'burette'burette coefficient'coefficient'coefficient'coefficient', shown as below:

Figure 7.3In order to ensure the accuracy and parallelism of the experimentalresults, user should reset the burette coefficient before the firsttitration.In addition, after use for long time, the instrument has been slight wear,the test need higher accuracy requirements which should calibratcalibratcalibratcalibrateeee

- 27 -

thethethethe buretteburetteburetteburette coefficientcoefficientcoefficientcoefficient againagainagainagain. The specific methods are as follows:In the initial interface, clean burette for several times, fill the burettewith distilled water (there can't be bubbles in the burette). Set theburette and set the burette coefficient as 100%. Take a clean weighingbottle, first weigh the empty bottle with the balance of 1/10000, putdripping tube into the weighing bottle, press 'Titration''Titration''Titration''Titration' button to enterinto titration mode, Choose the ''''macromacromacromacro titration'titration'titration'titration' and set titrationvolume, when it has been set up correctly, click ''''ConfirmConfirmConfirmConfirm'''', instrumentwill push a full burette distilled water to the weighing bottle, then weightwith balance, calculate the burette coefficient as follow.

100%* 0

12 ×−

=Vdggf

In which：f…………………Burette coefficient；g1…………………Weight of empty bottle；g2…………………Total weightd…………………The density of water；V0…………………The volume of the burette full degree

7.3.7.3.7.3.7.3. TimeTimeTimeTimeSet the current time. Click ''''TimeTimeTimeTime'''' in the interface，displayed as below:

Figure 7.4User can click on the corresponding blank area, to input corresponding

- 28 -

time through the digital keyboard key.8888.... VVVViewiewiewiewThere provides two ways of view: at the end of titration, user can viewthe titration data, in addition user can view the saved titration data.Note: In the titration process, if the user end titration quickly that resultin there have little titration data (less than 2), then users can't view thecurrent titration data; If the user have not saved titration data, therealso unable to view the saved data.In initial interface, press 'View''View''View''View' to check the corresponding titrationdata. Displayed as follows:

Figure 8.1In this interface, the user can view titration parameters, includingtitration time, burette volume, temperature and burette coefficient,electrode slope and so on, then the user clicks ''''PPPParameterarameterarameterarameterssss'''', it willdisplay:

- 29 -

Figure 8.2On the left side， it has three items: End point potential, End pointvolume and End point jump value. Click on ''''EPEPEPEP'''' at the bottom ofinterface, you can switch between several end points; Click onto see any point of the potential value on the titration curve, titrationvolume and jump value; click on 'P'P'P'Paaaaggggeeee Up'Up'Up'Up' and 'P'P'P'Paaaaggggeeee DDDDowowowown'n'n'n' to switchbetween titration results.In addition, click on ''''PPPPrintrintrintrint', it will print titration results which includeeach titration parameters and the titration curve.''''DDDDelete'elete'elete'elete' button is to delete the titration results that users do not need,this function can save instrument memory. Displayed as follows:Click on ''''DDDDelete'elete'elete'elete' to complete the delete.

- 30 -

Figure 8.39999、CalibrationCalibrationCalibrationCalibration (electrode(electrode(electrode(electrode calibration)calibration)calibration)calibration)When we need to accurately detect the pH of the solution, oraccurately detect the pH changes, we need to have electrodecalibration, before the start of the titration, all kinds of pH titration modeneed to have an electrode slope calibration.Before pH titration begins, electrode slope can be calibrated. If usersneeds to make two-point calibration, two kinds of standard buffersolutions must be prepared beforehand, if user needs to makeone-point calibration, then one kind of standard buffer solution isenough. Preparation of standard buffer solution is shown in Appendix.9.9.9.9.1111 One-PointOne-PointOne-PointOne-Point CalibrationCalibrationCalibrationCalibrationOne-point calibration means the electrode system is calibrated withonly one kind of pH standard buffer solution to calibrate automaticallythe potential of the instrument. The instrument will take percentageslope of pH combination electrode as 100%. This method can be usedto simplify the operation if precise measurement is not required. Theprocedure of operation is as follows:a. Insert pH combination electrode and temperature electrode intomeasuring electrode sockets, clean the electrode with distilled waterand put it in pH standard solution B (any one of the three pH standardbuffer solutions, General, first put in the standard solution of pH=6.86).

- 31 -

b. In initial interface, press 'Calibrate' button, displayed as follows:

Figure 9.1.1Press 'Electrode'Electrode'Electrode'Electrode oneoneoneone-point-point-point-point calibration'calibration'calibration'calibration' button, to enter intoone-point calibration working status. At this time, instrument displaysthe current measured pH value and temperature. Displayed as follows:

Figure 9.1.2c. When pH value tends to stable, the instrument displays percentageslope. Now one-point calibration has finished. Displayed as follows:

- 32 -

Figure 9.1.39.29.29.29.2 TTTTwo-pointwo-pointwo-pointwo-point calibrationcalibrationcalibrationcalibrationTwo-point calibration ensures pH measurement precise, which meansthe electrode system is calibrated with two standard solutions to obtainactual percentage slope and potential value of pH combinationelectrode. The operation procedure is as follows:a. In the 'calibration''calibration''calibration''calibration' menu item, click on ''''EEEElectrodelectrodelectrodelectrode twotwotwotwo----pointpointpointpointcalibration'calibration'calibration'calibration', that enter into two-point calibration work condition. Takeout the electrode, clean it with distilled water then, put it in pH standardbuffer solution B and A or C. Instrument displays current pH value andtemperature value, A or C standard buffer solution measurement stepsas the same as one-point calibration. Displayed as follows:

- 33 -

Figure 9.2.1b. When displayed pH value stable, instrument displays electrodeslope value, this means two-point calibration finished. Press 'SaveSaveSaveSave'button to quit from calibration panel. In the process of calibration, usercould stop calibration at any time by pressing 'ExitExitExitExit' button.

Figure 9.2.2In addition, in the two-point calibration process, if users forget tochange the second buffer solution, the instrument will give some hintsto remind users change buffer solution, Displayed as follows:

- 34 -

Figure 9.2.3

VVVV TTTThehehehe useuseuseuse ofofofof thethethethe electrodeselectrodeselectrodeselectrodes andandandand maintenancemaintenancemaintenancemaintenance

Correctly using the electrode directly affects the accuracy ofmeasurement results, therefore we should pay attention tomaintenance of the electrodes.AAAA MeasuringMeasuringMeasuringMeasuring electrodeelectrodeelectrodeelectrode :::: Measuring electrode first use should beprocessed, Glass sensitive membrane electrode need to soak intosaturated KCL solution for 8~24h. silver electrodes need to usesandpaper gently wipe the surface of it, washed with distilled water;platinum electrodes should be washed with chromic acid solution andthen washed with distilled water.BBBB ReferenceReferenceReferenceReference electrodeelectrodeelectrodeelectrode1. When using reference electrode, we should unplug charging mouthrubber plug, at the aid of gravity, the salt bridge solution to maintain acertain velocity with leakage test to solution path. The glass of the fillerand the rubber stopper should be often cleared.2. When measuring, the salt bridge liquid level of reference electrodeshould be higher than the DUT interface, which can prevent theproliferation of test solution to the calomel electrode. The test solutioncontains chlorides, sulfides, complexing agent, silver salt and

- 35 -

perchloric salts, if there has the inward diffusion, it will affect thepotential of the reference electrode.3. We should prevent bubble generation in reference electrodesolution, which can avoid measuring circuit break.4. Reference electrode electrolyte often added to replenish.1） Electrodes need to be cleaned, for example fat-containing liquidcan be added to a small amount of Multienzyme to help washing.2） Composite electrode not in use for a long time, it should be soakedin equal concentration of the reference solution inside the liquid.Balanced solution to keep the external reference, the loss is not easy.3） If not use reference electrode temporarily, it should be soaked indeionized water.4） The liquid junction of reference electrode or composite electrodeshould be maintain moist and smooth (to prevent crystallization), thatcan guarantee the stability of the reference potential.

VIVIVIVI.... MaintenanceMaintenanceMaintenanceMaintenance andandandand serviceserviceserviceservice ofofofof thethethethe instrumentinstrumentinstrumentinstrument

6666.1.1.1.1.... MaintenanceMaintenanceMaintenanceMaintenanceA. Keep the sockets of the instrument clean and dry, keep them awayfrom acidity, alkaline, salt solution, and also keep them damp-proof toensure insulation and high input impedance performance of theinstrument. When the instrument is not working, insert Q9 short circuitplug into the socket of measuring electrode to prevent it from dust andsteam. On the occasion that is with higher humidity, dry the plug of theelectrode with clean gauze firstly.1) Often clean the whole burette with distilled water, especially thetitrant which produces sediment or crystal ( eg. AgNO3), clean theburette in time after it is used.2) When using perchloric acid and Acetic acid as the titrant, keep theambient temperature ≥16°C, otherwise it will produce crystal, anddamage the valve.

- 36 -

6.2. Settle the common trouble:

Symptom Trouble cause Settlement

No display when start a. Power is off. a. Check the power.

mV/pH measurement

is not right.

a. electrode

performance is not

good.

b. Something wrong

with another electrode

interface.

c. Power connection is

not firm.

a. Change a new electrode.

b. Change Q9 short circuit plug.

c. Fix the power connection set

screws.

Printer doesn't work

or work incorrectly

a. Power of printer is

not connected.

b. Print line is not

connected.

c. Printer is set by

mistake.

d. Printer is selected

by mistake.

a. Connect printer power.

b. Connect print line.

c. Set correct printer type

d. Change the printer.

Macro titration can

not find the end point

a. End point jump is

too small.

b. Titrant or sample is

not right.

c. End point value is

too small.

d. Electrode is

selected by mistake.

a. Set jump value to "small".

b. Change titrant or correct the

sample.

c. Use "micro titration" mode.

d. Select electrode correctly.

Macro titration find

false end point

Parameter setting is

not appropriate

Increase the titration jump

- 37 -

Mode titration error

a. Find false end

point

b. Find false end

point

Pre-titration find false

end point

b. Mode select error

a. Close the false end point

b. Choose the right titration mode

End point setting

titration error

a. Two or more end

points, parameter

setting finished,

unable to titration

b. Titration, shows

"pre-control range

setting error"

Parameter setting

error

a. Set the right parameter

b. Set the correct pre-control range

Agitator is not

working

a. Agitator was not

connected

b. Stirring set wrong

c. Agitator was bad

d. No magneton in

titration cup

a. Connect to stirrer.

b. Accelerate mixing speed

c. Change agitator

d. Place magneton into titration cup

Infusion tube have

bubbles

Infusion tube interface

leakageInstall infusion tube again

according to the instructions

Machine doesn't

work normally

Burette installed

wrongReinstall the burette

Electrode calibration

error

a. poor performance of

PH electrode.

b. Buffer prepared

error

a. Change PH electrode

b. Prepare buffer solution again

- 38 -

VII.VII.VII.VII. SupportingSupportingSupportingSupporting instrumentinstrumentinstrumentinstrument

1、Automatic titrator main unit 1 set2、Stirring stand 1 set3、Accessories 1 set

VIVIVIVIIIIIIIII.... AppendixAppendixAppendixAppendix

1. pH standard buffer solution A (pH 4.01, 25 °C)Weigh 10.12g of KHC8H4O4 that has been dried under 110°C~130°Cfor 2-3 hours, dissolve it in 1L of de-ion water.2. pH standard buffer solution B (pH 6.86, 25°C)Weigh 3.388g of KH2PO4 and 3.533g of Na2HPO4 respectively,dissolve it in 1L of de-ion water.3. pH standard buffer solution C (pH 9.18, 25°C)Weigh 3.80g of Na2B4O7, H20 which was put in the desiccator withsaturated NaBr for two days, dissolve it in 1L of de-ion water.