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kruss K11 MK3 User Manual

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Tensiometer K11 MK3
User Manual
V3.05
© KRÜSS GmbH, Hamburg 2000-2010

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Summary of Contents for kruss K11 MK3

  • Page 1 Tensiometer K11 MK3 User Manual V3.05 © KRÜSS GmbH, Hamburg 2000-2010...

  • Page 3: Table Of Contents

    Contents page 1 Contents 1 General information ..................7 General safety instructions....................7 Intended use ........................8 Procedure if repairs should be necessary ................8 Technical support......................10 2 Introduction ....................11 3 Setup and starting up................... 12 Transport.......................... 12 Location and ambient conditions..................
  • Page 4 page 2 Contents The keypad ........................25 4.6.1 Measuring method selection (plate, ring, density) ............27 4.6.2 Starting and stopping measurements................. 27 4.6.3 Entering measuring parameters ................. 28 4.6.4 Changing the basic settings (setup) ................29 4.6.5 Illumination ......................... 30 4.6.6 Stirrer .........................
  • Page 5 Contents page 3 Measuring surface tension by the plate method............... 43 Measuring interfacial tension by the plate method ............44 8 Ring method measurements................ 47 Measuring parameters in the main menu of the ring method ........... 47 8.1.1 Measuring mode ......................47 8.1.2 Correction........................
  • Page 6 page 4 Contents 10.2.2 Sensitivity ........................70 10.2.3 Min. standard deviation ....................71 10.2.4 Number of values for SD .................... 71 10.3 Third page of the setup menu ..................72 10.3.1 Stirrer speed....................... 72 10.3.2 Oscillating period......................72 10.3.3 Temperature sensor ....................72 10.3.4 Language / Sprache ....................
  • Page 7 Contents page 5 14 Thermostatting the gas phase with the TJ20 (optional) ......96 15 Measuring principles .................. 99 15.1 Surface and interfacial tension..................99 15.1.1 The ring method according to Du Noüy..............99 15.1.2 The plate method according to Wilhelmy ..............101 15.1.3 Ring and plate methods in comparison ..............

  • Page 9: General Information

    General information page 7 General information General safety instructions As well as this general safety information, please follow the safety instructions in the remainder of the manual text. The K11 is intended for use in a laboratory or pilot plant station. The general safety rules for working in a laboratory environment apply to work carried out with the K11.

  • Page 10: Intended Use

    page 8 General information Intended use • K11 is intended only for measurements of the surface tension of liquids, the interfacial tensions between two liquids and measurements of the density of a liquid. • The intended use includes the exclusive use of accessories supplied by KRÜSS or substitutes with an identical design if disposable accessories are being used.
  • Page 11 General information page 9 Send us the measuring instrument or accessories Do not dispatch the measuring instrument or accessories without consulting KRÜSS customer support. Components which are not directly affected by the damage may also have to be sent with the unit. KRÜSS customer support will advise you on the necessary scope of the shipment.

  • Page 12: Technical Support

    General information Technical support If problems should occur when working with the K11 or with LabDesk, please consult the technical customer support at KRÜS GmbH. You can contact them at: KRÜS GmbH Technical support Tel:(+49) 040/514401-0 Fax:(+49) 040/514401-98 E-mail: info@kruss.de...

  • Page 13: Introduction

    This manual is subject to a permanent quality control. The current version of the manual can always be acquired from the download section of our homepage www.kruss.de Possible uses of the K11 • measurements of the surface tension of a liquid with the Du Noüy ring or Wilhelmy plate method as well as the rod method •...

  • Page 14: Setup And Starting Up

    page 12 Setup and starting up Setup and starting up Transport Two people are required for transporting the K11. Remove any sample vessels from the sample platform before transporting. Before transport, close the doors of the measuring chamber and safe them with adhesive tape Transport the K11 with the help of a trolley.

  • Page 15: Levelling The Instrument

    Setup and starting up page 13 Avoid contamination of the sample liquid by atmospheric air (e.g. by exhaust from • machines). • Avoid devices emitting hertzian waves near the instrument (e.g. cell phones, W- LAN devices). These can affect the force sensor electronics and lead to measurement errors.

  • Page 16: Connectors And Connections

    page 14 Setup and starting up Connectors and connections 3.4.1 Power supply LINE Connect the mains cable to the connector on the back of the K11. Connect the mains plug supplied to a mains outlet (100-240 V AC). 3.4.2 Connecting the K11 Control Panel Control Panel : Control keypad for control of the K11.

  • Page 17: Computer Connection (Optional)

    Setup and starting up page 15 3.4.3 Computer connection (optional) The K11 is connected to the computer via a serial interface. SERIAL PC Connect the interface connector on the back of the K11 to a corresponding interface on the computer. 3.4.4 Connecting an external thermostat (optional) THERMOSTAT IN...

  • Page 18: Assembling A Thermostat Jacket (Optional)

    page 16 Setup and starting up Assembling a thermostat jacket (optional) Unplug the K11 from the mains before assembly. 1. If you have ordered the optional TP0512 external temperature sensor: Attach the temperature sensor bracket to the thermostat jacket before fitting the vessel p.
  • Page 19 Setup and starting up page 17 4. Slide the rubber sleeve over the shaft as far as the lower edge of the vessel. 5. Connect the two Quick-Lock closures of the hoses coming from the thermostat jacket to the two sockets in the sample chamber.

  • Page 20: Assembling An External Temperature Measuring Probe (Optional)

    page 18 Setup and starting up 3.5.1 Assembling an external temperature measuring probe (optional) 1. Turn the thermostat jacket over. Attach the bracket for the temperature sensor to the underside of the thermostat jacket with the help of the two screws supplied. 2.

  • Page 21: Installation Of The Protocol Printer (Optional)

    Setup and starting up page 19 3.5.3 Installation of the protocol printer (optional) SERIAL PC Connect the interface connector on the back of the K11 to the protocol printer. Connect the printer to the mains supply using the net adapter supplied.

  • Page 22: Operating The Instrument

    page 20 Operating the instrument Operating the instrument An exact description of the measuring methods and basic settings is given in chapters 7 to 10. When making a measurement you will work alternately on the K11 instrument and with the control panel. All manual activities as suspending the probe or positioning the sample are made on the K11.

  • Page 23: Resetting The Instrument

    Operating the instrument page 21 To switch the K11 to standby mode: Press the key for at least two seconds. 4.1.3 Resetting the instrument RESET If the K11 no longer responds to the Control Panel: Press the button on the back of the K11.

  • Page 24: The Control Panel (Overview)

    page 22 Operating the instrument The control panel (overview) Measuring method selection, control of the measuring procedure and measuring parameter input are carried out via the control panel. The height adjustment of the sample vessel is also carried out via the control panel. Display (ch.

  • Page 25: Moving The Sample Stage

    Operating the instrument page 23 The lower area contains instructions for the steps to be carried out during a • measurement. The actions which can be carried out from the particular menu item are also shown here. The brightness of the display can be altered with the small rotary knob on the back •...

  • Page 26: Moving The Sample Platform Using The Rotary Knob

    page 24 Operating the instrument 4.5.2 Moving the sample platform using the rotary knob To raise the sample stage: Turn the rotary knob clockwise (in the direction). Down To lower the sample stage: Turn the rotary knob anticlockwise (in the direction).

  • Page 27: The Keypad

    Operating the instrument page 25 The keypad The following functions can be accessed via the keypad: Measuring method selection (plate, ring, density measurement) • • Starting and stopping measurements • Entering measuring parameters • Changing the basic settings (setup) switching illumination on/off •...
  • Page 28 page 26 Operating the instrument Functions nos. 4,5,6 when entering parameters letters G to O and nos. 4,5,6 when entering text Main function: switching illumination on/off Secondary functions: no. 7 when entering parameters letters P,Q,R,S,7 when entering text Main function: switching stirrer on/off Secondary functions: no.

  • Page 29: Measuring Method Selection (Plate, Ring, Density)

    Operating the instrument page 27 4.6.1 Measuring method selection (plate, ring, density) • With the three keys you can select between the three measuring methods. • From the main menu of a measuring method you can use the key to select the mode for parameter entry or the key to start a measurement with the selected method.

  • Page 30: Entering Measuring Parameters

    page 28 Operating the instrument 4.6.3 Entering measuring parameters In the two methods for determining the surface and interfacial tension (ring and plate methods) and in the density determination suitable parameters must be entered for the particular application. • You can access the corresponding submenus by pressing the key in each of the relevant main menus.

  • Page 31: Changing The Basic Settings (Setup)

    Operating the instrument page 29 If you press the key • briefly then a return is made from any point in the parameter input mode to the particular main menu. All confirmed entries made up to this point are retained; however, if entries have been made in an input line which have not been confirmed by either ENT or one of the vertical arrow keys then such entries will be rejected when the ESC-key is pressed.

  • Page 32: Illumination

    page 30 Operating the instrument 4.6.5 Illumination When the instrument is switched on the measuring chamber illumination is switched on automatically. The illumination releases only a small amount of heat so that the measuring chamber temperature does not change. If you want to work without any illumination you can switch the light on and off with the key You cannot use this function when you are in the parameter input mode for the measuring methods or setup, as the key is then used for entering numbers or...

  • Page 33: Suspending The Measuring Probes

    Operating the instrument page 31 Suspending the measuring probes Application of force at the measuring probe and the ring in particular easily deforms the probe and makes it useless. When removing the measuring probe from the socket allow it to slide gently into your open hand.

  • Page 34: Cleaning Procedures

    page 32 Cleaning procedures Cleaning procedures Before starting a measurement the sample vessel SV20 and the measuring probes must be cleaned intensively. The accuracy and reproducibility of the measurements depend on how thoroughly the cleaning process is performed. Please follow the cleaning instructions provided in this section.

  • Page 35: Step 3 (If Necessary): Scarfing

    Cleaning procedures page 33 5.1.3 Step 3 (if necessary): Scarfing Scarf the sample vessel with the flame of a Bunsen burner. When scarfing use crucible tongs and wear fire-proof gloves. Allow the glass to cool on a heat-resistant sheet before using it again. Risk of injury due to shattering glass If the glass should shatter, slivers of glass may cause injury.

  • Page 36: Cleaning The Measuring Probe For Determining The Density

    page 34 Cleaning procedures In both cases the probe must then by heated up to red heat with a gas burner. Risk of burning by naked flames and heated metal If you touch a naked flame or heated measuring probe you will burn yourself.

  • Page 37: Preparing A Measurement

    Preparing a measurement page 35 Preparing a measurement Safety information 6.1.1 Working with highly flammable liquids Fire hazard due to highly flammable liquids When working with highly flammable liquids a flammable gas mixture can emerge in WARNING the chamber. After opening the chamber doors, wait for a moment for the vapour to escape before you continue working at the instrument.

  • Page 38: Setting Up And Filling The Sample Vessel

    page 36 Preparing a measurement At temperatures higher than 70°C the space above the surface gets hot. To avoid overheating of the balance system, the doors of the measurement chamber should be kept open and only be closed when a measurement is running. The (optional) gas space thermostatting system TJ20 can help avoiding temperature changes even when the measurement chamber is open.

  • Page 39: General Course Of A Measurement

    Preparing a measurement page 37 In the second stage the heavy phase is filled into an empty sample vessel. The • height should also be at least twice the immersion depth. After the probe has touched the surface the lighter phase is carefully layered over the heavy phase. This is best done by running it down the glass wall from a pipette.

  • Page 40: Check List Before Starting A Measurement

    page 38 Preparing a measurement Check list before starting a measurement The following preparations should have been made before a measurement is started: • A warming-up period of 2 hours must be observed directly after the instrument is switched on. Plate Ring Density...

  • Page 41: Measurements With The Plate Or Rod Method

    Measurements with the plate or rod method page 39 Measurements with the plate or rod method Measuring with a rod is assigned to the plate measuring method. When measuring ch. 7.1.4 ). Apart with a rod the wetted length of the rod used must be entered ( from that, the same instructions as for the plate method apply.

  • Page 42: Reading Limit

    page 40 Measurements with the plate or rod method 7.1.2 Reading limit The result at the end of a measurement is an arithmetic average value calculated from maximum a certain number of single measurements. This is where you enter the number of these single measurement values.

  • Page 43: Parameters For The Plate Method In Setup

    Measurements with the plate or rod method page 41 For the rod a smaller amount of test liquid is required due to the shorter wetted length. However, the results are slightly less accurate when the wetted length is shorter. Determine the diameter of the rod as close to the lower edge as possible and with an accuracy of at least 10 μm.

  • Page 44: Detection Speed (Mm/Min)

    page 42 Measurements with the plate or rod method 7.2.2 Detection speed (mm/min) At the start of the measurement the sample stage is first moved upwards. The contact between the plate and the surface of the liquid is registered owing to the change in force;...

  • Page 45: Measuring Surface Tension By The Plate Method

    Measurements with the plate or rod method page 43 Measuring surface tension by the plate method Check whether all the requirements contained in the check list ( ch. 6.5) have been met. Select the measuring mode . Start the measurement with ENT key. The following table shows the course of the measurement: Plate method: Surface Tension Display...

  • Page 46: Measuring Interfacial Tension By The Plate Method

    page 44 Measurements with the plate or rod method Display Action Explanation Immersing Immerses the probe to the given automatic immersion depth. Returns to the found surface height. Measuring Records the measured values. automatic Displays the individual measured values Finished The measurement is complete.
  • Page 47 Measurements with the plate or rod method page 45 Display Action Explanation Only if defined in Enter the required The text fields, whose number is Setup: contents in the text defined in Setup, are called up in fields succession (max. 3) and are used Field In succession to describe the measurement.
  • Page 48 page 46 Measurements with the plate or rod method Display Action Explanation Searching Searches for the surface: the liquid automatic is moved upwards until the probe “jump“ is registered. The surface position is stored. Immersing Immerses the probe to the given automatic immersion depth.

  • Page 49: Ring Method Measurements

    Ring method measurements page 47 Ring method measurements Measuring parameters in the main menu of the ring method To access the main menu of the ring method press the key The following display appears: You will find the current settings for measurements with the ring method in the centre. If you want to retain the settings then you can start the measurement with the ENT-key.

  • Page 50: Correction

    page 48 Ring method measurements Pull : In most liquid systems the heavy phase also has the larger surface • tension (e.g. water/hexane). In such cases the ring is completely immersed in the heavy phase, which is then carefully overlayered by the lighter phase. During the measurement the film is then pulled upwards from the heavy phase into the lighter phase.
  • Page 51 Ring method measurements page 49 Zuidema & Waters (3) : The two authors of this method carried out interpolation • calculations on the data measured by Harkins & Jordan. The method is intended for interfacial tension measurements, but has a larger range of variation than the correction according to Harkins &...

  • Page 52: Reading Limit

    page 50 Ring method measurements 8.1.3 Reading limit The result at the end of a measurement is an arithmetic average value calculated from maximum a certain number of single measurements. This is where you enter the number of these single measurement values. Ten measurements are usually sufficient. In case of higher variations this number can be increased.

  • Page 53: Ring Type

    Ring method measurements page 51 For example, if you enter 10% and the maximum force determined in the first measurement is found to be 800mg then before the next measurement the liquid will be moved from the maximum position until a value of 720mg is measured (800mg-(800mg*10%)=720mg).

  • Page 54: Parameters For The Ring Method In Setup

    page 52 Ring method measurements Parameters for the ring method in Setup Setup The first two pages of the menu contain parameters which affect the course of the measurement with the plate method. Assumingly, they rarely need to be altered. Only those parameters which are relevant for the ring method are described here;...

  • Page 55: Immersion Depth

    Ring method measurements page 53 8.2.3 Immersion depth This is the distance by which the sample stage is moved upwards after detection of the surface in order to immerse the ring in the liquid. This immersion only ensures a more rapid and better wetting of the ring;...

  • Page 56: Measuring Surface Tension By The Ring Method

    page 54 Ring method measurements Measuring surface tension by the ring method Check whether all the requirements contained in the check list ( ch. 6.5) have been met. Select the measuring mode . Start the measurement with ENT key. The following table shows the course of the measurement: Ring method: Surface Tension Display Action...
  • Page 57 Ring method measurements page 55 Display Action Explanation Immerses the probe to the given immersion depth. Immersing automatic Returns to the found surface height. Measuring Records the measured value: automatic Displays the The sample vessel containing the measured value liquid moves down until a maximum force is registered.

  • Page 58: Measuring Interfacial Tension By The Ring Method

    page 56 Ring method measurements Measuring interfacial tension by the ring method The two following subsections describe the course of the measurement for the IFT pull IFT push measuring methods Chapter 8.1.1 describes which method applies to which liquid system. 8.4.1 Interfacial tension pull Check whether all the requirements contained in the check list (...
  • Page 59 Ring method measurements page 57 Display Action Explanation Insert the light Insert the sample phase and vessel containing immerse the the light phase and probe completely move the sample upwards until the ring is covered. Taring Taring the probe in the light phase automatic Remove the light Carry out activities...
  • Page 60 page 58 Ring method measurements Display Action Explanation Measuring Returns to the found surface automatic height. Displays the measured value Records the measured value: The sample vessel containing the liquid moves down until a maximum force is registered. The vessel is moved back upwards; the value of the maximum force is now determined exactly.

  • Page 61: Interfacial Tension Push

    Ring method measurements page 59 8.4.2 Interfacial tension push Check whether all the requirements contained in the check list ( ch. 6.5) have been met. IFT-push Select the measuring mode . Start the measurement with ENT key. The following table shows the course of the measurement: Ring method: Interfacial tension push Display Action...
  • Page 62 page 60 Ring method measurements Display Action Explanation Insert the heavy Add the heavy phase and the light phase and carefully overlay and dip the ring it with the light phase, into the light phase best done by running it down the vessel side from a pipette.
  • Page 63 Ring method measurements page 61 Display Action Explanation The liquid is moved downwards again until the maximum force is reduced by the percentage value Relaxation given under Relaxing automatic Measuring The steps Relaxing are repeated until all the measurement has been completed.

  • Page 64: Density Measurement

    page 62 Density measurement Density measurement You can also determine the density of liquids with the aid of the optionally available density determination set for the K11. If you need density values for measuring the interfacial tension by the ring method you can measure them directly with the K11. Parameters for the density measurement in Setup The first two pages of the setup menu also contain parameters which affect the course of the measurement of the density.

  • Page 65: Immersion Speed (Mm/Min)

    Density measurement page 63 9.1.2 Immersion speed (mm/min) When the probe holder has been tared and the weight of the probe has been measured the holder is immersed in the liquid. At a later stage the holder is immersed in the liquid for a second time together with the probe. The speed at which this takes Immersion speed place is defined under .
  • Page 66 page 64 Density measurement The following table shows the course of the measurement: Density measurement Display Action Explanation Sample: Insert the sample Maximum 22 characters and use the keypad insert the sample to enter a sample and enter a name name.
  • Page 67 Density measurement page 65 Display Action Explanation Remove the stick proceed according from the hook, to the instructions insert the liquid on the display and position the hook above the surface The sample vessel is moved upwards at the entered search Searching automatic speed until the contact between...

  • Page 68: Entering The Density Of A Different Probe

    page 66 Density measurement Display Action Explanation Immersing The sample vessel is moved automatic upwards again until the probe is completely immersed. Measuring automatic The weight of the probe in the liquid is measured. Finished The measurement is complete. automatic The data found are used to Displays the final calculate and display the density.

  • Page 69: Basic Settings (Setup Menu And Special Functions)

    Basic settings (setup menu and special functions) page 67 Basic settings (setup menu and special functions) This section provides you with the necessary information for making the basic settings in the setup menu. The settings made here normally only need to be altered on rare occasions;...

  • Page 70: First Page Of The Setup Menu

    page 68 Basic settings (setup menu and special functions) 10.1 First page of the setup menu The speeds for the various movement steps in the measuring procedure are set on this page. In principle, the values pre-set by KRÜSS can be retained in most cases. All speeds should be reduced when a very viscous or viscoelastic liquid is involved.

  • Page 71: Detection Speed

    Basic settings (setup menu and special functions) page 69 10.1.3 Detection speed In order to measure surface or interfacial tension the boundary must first be found. This is done by moving the sample upwards until the contact with the liquid is registered. detection speed is the speed of movement during the search for the interface.

  • Page 72: Second Page Of The Setup Menu

    page 70 Basic settings (setup menu and special functions) 10.2 Second page of the setup menu 10.2.1 Immersion depth When a surface or interface has been found the probe is immersed in the liquid or the heavy phase in order to improve its wettability. The depth to which the probe is to be immersed is entered here.

  • Page 73: Min. Standard Deviation

    Basic settings (setup menu and special functions) page 71 10.2.3 Min. standard deviation This is where you enter what limit for the absolute Standard Deviation for the measurement will be regarded as being accurate enough to automatically finish the measurement. For example, if a value of 0.2 mN/m is entered then a check will be made whether the standard deviation of previously recorded values is higher than 0.2 mN/m.

  • Page 74: Third Page Of The Setup Menu

    page 72 Basic settings (setup menu and special functions) 10.3 Third page of the setup menu 10.3.1 Stirrer speed When measuring the surface tension of emulsions and dispersions it may be necessary to stir the liquid until just before the measurement is made. This is why we have included a stirrer function;...

  • Page 75: Language / Sprache

    Basic settings (setup menu and special functions) page 73 auto With the setting (number 3) the Firmware will automatically check which temperature sensors available select appropriate sensors automatically. If both sensors are available then the external sensor will be selected automatically.

  • Page 76: Fourth Page Of The Setup Menu

    page 74 Basic settings (setup menu and special functions) 10.4 Fourth page of the setup menu This where the general data concerning the measurement are entered; these then appear on the printout and on transfer to the computer. text fields •...

  • Page 77: Fifth Page Of Setup Menu

    Basic settings (setup menu and special functions) page 75 10.5 Fifth page of Setup menu On the fifth page you have the possibility of protecting access to the Setup menu by using a password. You can also return all the Setup settings to the default values defined by KRÜSS.

  • Page 78: Special Functions

    page 76 Special functions Special functions With the key you get to a menu containing special functions. Cal. (external) The function (7) is described in ch. 13.3. The display does not show the current setting but the setting that is reached by pressing the corresponding number key.

  • Page 79: Labdesk Output / Standard Output (3)

    Special functions page 77 11.3 LabDesk output / Standard output (3) This option is used for setting up data output for the printer or the data table in output LabDesk . If LabDesk is switched on then data transfer to LabDesk takes place in CSV-format which can be processed by LabDesk.

  • Page 80: Data Transfer To External Media (Optional)

    page 78 Data transfer to external media (optional) Data transfer to external media (optional) There are two ways of transferring data to external media: Printout on a protocol printer ( ch. 12.1 ) • ch. 12.2 ). • Transfer to a PC using the KRÜSS LabDesk tensiometer software ( 12.1 Printing out on a protocol printer 1.

  • Page 81: Pc Transfer To Labdesk

    Data transfer to external media (optional) page 79 12.2 PC transfer to LabDesk 12.2.1 Installation The computer system requirements are listed in the Appendix IV. Software installation 1. Close all Windows applications with the exception of Explorer. 2. Insert the LabDesk CD. If the installation program does not start automatically: Setup.exe Start the program in the root directory of the CD.
  • Page 82 page 80 Data transfer to external media (optional) Product key Activation 6. Enter the and the Next for your LabDesk version. Click on 7. Enter the user name specified in the registration documents for your LabDesk Next version. Click on 8.
  • Page 83 Data transfer to external media (optional) page 81 11. A name for a LabDesk program folder in the Windows Start Menu will be proposed. Click Next to accept the name or enter a name of your own. 12. The directories created will be listed. Start Install the installation with Finish...
  • Page 84 page 82 Data transfer to external media (optional) Install the software automatically 5. Select the option for the driver installation and click on Next. Browse If the Driver was not located by the wizard it can be selected with in a Drivers USBRS232 further Step.

  • Page 85: Preparations

    Data transfer to external media (optional) page 83 12.2.2 Preparations Changing the output format Connect the serial “RS-232” interface connection on the rear panel of the K11 (optionally: the USB port) to a referring interface on the computer. Special Functions Select the menu (*-key) of the K11.

  • Page 86: The Toolbar

    page 84 Data transfer to external media (optional) 12.2.3 The toolbar Icon Function Remarks/Explanation Calls up a new Data-Logger window. Already recorded data must be saved, as it is deleted when a new window is opened Opens a saved file Open Saves the measuring data shown in the Data- Saving...

  • Page 87: Data Transfer

    Data transfer to external media (optional) page 85 12.2.4 data transfer 1. Activate data transfer with the button. 2. Start the K11 measurement. General information about the measurement appears in the Data-Logger window, transferred measured values are listed below: 3. Data transfer is terminated with the button when the measurement or series of measurements are complete.

  • Page 88: Data Export

    page 86 Data transfer to external media (optional) 12.2.5 Data export Information in the Data-Logger window can be exported to other programs via the Windows clipboard. Mark the data to be exported with the mouse. Click on the button to copy the data to the clipboard. Data can now be imported into other programs from the clipboard.
  • Page 89 Data transfer to external media (optional) page 87 Translate Language […] when Loading a File With the option you can also • convert the data table automatically when it is opened. The target language for the conversion is not given by the language of the program interface, but from the language of your Windows version.
  • Page 90 page 88 Data transfer to external media (optional) Definition of text fields: Field names tab sheet On the fourth page of the K11 Setup menu you can define the number of text fields to be used ( ch. 10.4). Names are assigned to the fields in LabDesk. Start Capture 1.
  • Page 91 Data transfer to external media (optional) page 89 General settings Extras General Preferences The basic settings for LabDesk can be made under General For K11 only the entries on the tab are applicable. View • In the section elements of the LabDesk user interface can be shown or hidden.

  • Page 92: Maintenance

    page 90 Maintenance Maintenance 13.1 Checking the shape of the probes The accuracy of measurements depends on the proper shape of the measuring probes. By careless handling the probes can easily be damaged and made useless. 13.1.1 The ring The ring must always be handled very carefully as it is easily deformed. If the ring is not absolutely plane and round then there will be large measuring errors.

  • Page 93: The Plate

    Maintenance page 91 13.1.2 The plate Check visually if the surface of the plate is rough in order to obtain a perfect wetting of the plate. If blank spots are already visible on the plate then it should no longer be used.

  • Page 94: Adjusting The K11

    page 92 Maintenance 13.3 Adjusting the K11 To adjust the K11 the adjustment set CP0503 with a 100g weight is required. Remove the sample vessel or other fragile objects from the sample stage. These could be damage when the weight is dropped inadvertently. Never touch the weight or hook with your fingers, but only with tweezers.

  • Page 95: Downloading Current Firmware

    Maintenance page 93 13.4 Downloading current firmware www.kruss.de. Login 1. Go to our website Click on Username Password Login 2. Enter your . Click on You should have received the user name and password by e-mail shortly after delivery of the K11. If you do not have this information, please register using the...
  • Page 96 page 94 Maintenance Software Updates 4. Click on K11, 5. Under download the ZIP archive with the filename that indicates the highest firmware number. Log-Out 6. Click on Loading the firmware 1. Extract the ZIP-archive in a temporary directory. Information for using the ZIP program is given in the corresponding documentation.
  • Page 97 Maintenance page 95 5. The next step is to enter the KRÜSS Tensiometer (K11 or K100) which is Enter the instrument code <1=K11; 2=K100> connected: . Enter the number 1 for the K11 and press the ENTER key of the computer keyboard. 6.

  • Page 98: Thermostatting The Gas Phase With The Tj20 (Optional)

    page 96 Thermostatting the gas phase with the TJ20 (optional) Thermostatting the gas phase with the TJ20 (optional) Temperature variations at the interface cause a measuring inaccuracy which increases as the temperature increases. With the aid of the optional TJ20 System this error can be avoided by thermostatting the gas phase above the interface.
  • Page 99 Thermostatting the gas phase with the TJ20 (optional) page 97 As a result of its superior heat exchange ability the liquid phase can usually be better thermostatted than the gas space above the liquid; this is why the temperature of the gas space is normally lower than that of the liquid. This effect can be compensated by thermostatting the gas phase separately with a second thermostat.
  • Page 100 page 98 Thermostatting the gas phase with the TJ20 (optional) 4. Insert the supplied measuring probe adapter into the measuring probe holder. measuring probe adapter 5. Insert the measuring probe into the measuring probe adapter. Move the sample stage upward until the probe is located just above the liquid surface. 6.

  • Page 101: Measuring Principles

    Measuring principles page 99 Measuring principles This chapter contains a brief introduction into the principles of the measuring methods integrated in the K11. 15.1 Surface and interfacial tension Due to the attractive forces between molecules (cohesion) a certain work is necessary to change the size of a liquid interface or surface.
  • Page 102 page 100 Measuring principles As the film is stretched a maximum force is experienced; this is recorded in the measurement. At the maximum the force vector is exactly parallel to the direction of motion; at this moment the force correlates to the surface or interfacial tension. The contact angle θ...

  • Page 103: The Plate Method According To Wilhelmy

    Measuring principles page 101 Correction For ring measurements the measured values must be corrected since the results are otherwise falsified by two effects: • The weight of the uplifted amount of liquid underneath the ring increases the value of the force detected by the force sensor. •...

  • Page 104: Ring And Plate Methods In Comparison

    page 102 Measuring principles The tension is calculated using the following equation: σ θ ⋅ (σ = surface or interfacial tension; F = force acting on the balance; L = wetted length, θ = contact angle). The plate is made of roughened platinum and is optimally wetted so that the contact angle is virtually 0¡ã.

  • Page 105: Density Measurement

    Measuring principles page 103 Advantages of the ring method Many international standards for surface and interfacial tension measurements still • base upon the ring method. • Many values in the literature have been obtained with the ring method. This means that in many cases the ring method should be preferred for comparison purposes.

  • Page 106: Appendix

    page 104 Appendix Appendix Ranges of validity for the ring correction methods The following table provides information about the range of validity of the correction methods implemented in the K11. In order to select the suitable correction method for your application you should find the line containing the density difference of the system to be measured and check whether the expected surface or interfacial tension lies within the range of validity for the correction method.

  • Page 107: Settings For Compatibility With The Tensiometer K10

    Appendix page 105 Settings for compatibility with the Tensiometer K10 Customers who own K10 Tensiometers can set the parameters for the K11 so that it behaves in exactly the same way as a K10. However, this possibility is only provided to allow comparative measurements.

  • Page 108: Error Messages

    page 106 Appendix Light density: not relevant with linear correction (4) Relaxation: not relevant with linear correction (4) Reading limit Min. standard deviation: not relevant because Reading limit Number of values for SD: not relevant because Error messages If an error occurs in controlling the instrument or when carrying out a measurement then a corresponding error message will appear on the display.
  • Page 109 Appendix page 107 Error No. Fault Appearance Remedy Underload (force Appears if attaching and Remove load and pressing against removing the weight when press ESC key to balance from adjusting the instrument or switch instrument off below is too if the motor presses the and on.

  • Page 110: Computer Requirements For Labdesk

    page 108 Appendix Computer requirements for LabDesk The following is a list of the minimum requirements to enable LabDesk to run without any problems: IBM-AT or compatible computer • • CD-ROM drive Hard disc with at least 200 MB free memory •...

  • Page 111: Technical Data

    Appendix page 109 Technical data Weight 21 kg Dimensions (W x D X H) 300 x 390 x 585 mm Power supply 85-264 V AC (40-60Hz) Power consumption (standby) ca. 4 W Power consumption (during max. 40 W measurement) Resolution, density 0.001 g/cm Measuring range, density 0 –...

  • Page 112: Copyright And Right To Make Alterations

    page 110 Appendix Copyright and right to make alterations The information contained in this document may be altered without notice and does not represent any obligation by KRÜSS GmbH. Neither this manual nor any part of it may be reproduced or transmitted for any purpose whatsoever in any form and by any means, electronic or mechanical, by photocopy or drawing without the express approval of KRÜSS GmbH in writing.

  • Page 113: Index

    Appendix page 111 VIII Index acceleration due to gravity......69 gravitational acc..........69 basic settings......29, Setup Harkins & Jordan .......... 48 beep on /off............76 Huh & Mason ..........48 company name ..........74 illumination ............ 30 compatible to K10........105 immersing speed........... 41 control panel ..........22 immersion depth ........
  • Page 114 page 112 Appendix relaxation ..............50 surface tension ............54 ring tear-off measurement ......51 oscillating period..........72 ring-method tear-off measurement ..........51 rod method............ 39 password ............75 plate method detection speed speed ..........42 sample vessel filling level..............36 immersing speed .............41 filling................

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