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MICROTEST MATERIALS TESTING

MODULES OPERATION MANUAL V6.11

© Deben UK Ltd. 2012

Brickfields Business Park, Woolpit Bury St. Edmunds, Suffolk IP30 9QS. UK

Tel: +44 (0) 1359 244 870, Fax: +44 (0) 1359 244 879 Web: Hwww.deben.co.uk H E-mail: [email protected]

Registered in England No. 3208255

Registered Office: Unit 19 Charlwoods Road, East Grinstead, West Sussex, RH19 2HL, U.K.

Deben MICROTEST Version 6.11

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CONTENTS INTRODUCTION ..................................................................................................... 2 PC SPECIFICATION – MINIMUM REQUIREMENTS ............................................ 2 THE WARNING BUZZER ....................................................................................... 3 INSTALLATION ....................................................................................................... 4

INSTALLING THE MODULE INTO AN SEM ............................................................... 4 INSTALLING THE MODULE FOR NON SEM USE ....................................................... 4 CONNECTING THE SYSTEM .................................................................................. 5 INSTALLING THE MICROTEST SOFTWARE .............................................................. 6

THE MICROTEST SOFTWARE ........................................................................... 11 GETTING STARTED ............................................................................................ 11 QUICK START TEST PROCEDURES ................................................................. 15

RUN A BASIC TENSILE TEST ............................................................................... 15 RUN A COMPRESSION TEST ............................................................................... 16 RUN A BASIC VERTICAL BENDING TEST ............................................................... 17

SOFTWARE OPERATION .................................................................................... 18 CONTROL MENU ................................................................................................ 18 DATA READOUT DISPLAYS ................................................................................. 18 SIMPLE MOTOR OPERATION ............................................................................... 19 GOTO FUNCTIONS ............................................................................................. 22 SOFTWARE MENU ITEMS .................................................................................... 23

MOUNTING A SAMPLE ........................................................................................ 37 DEMO MODE ........................................................................................................ 37 APPENDIX 2 – DATA FILES ................................................................................ 38 APPENDIX 3 – P/I VALUES ................................................................................. 39 APPENDIX 4 - SYSTEM SETTINGS .................................................................... 40 APPENDIX 5 – CHINESE ROHS DECLARATION ............................................... 41

THIS VERSION OF SOFTWARE REQUIRES V2.0 (OR HIGHER) FIRMWARE AND THE V2.0 (OR HIGHER) TACHOMETER IC.

DO NOT USE THIS SOFTWARE WITH EARLIER VERSIONS OF FIRMWARE.


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Introduction

Deben MICROTEST tensile/compression/bending stages are primarily designed for use within the confined space of an SEM chamber although they are also suitable for use with optical microscopes, AFM, X-Ray Diffraction machines or as data logging test modules.

The modules allow many different materials to be deformed and stretched at loads of up to 500Kg (5KN). The maximum load depends on the load cell fitted. Different modules and load cells are available from 2N to 5KN; the choice depends on the type of sample and the tests being carried out.

Acquisition software, which will run under Windows XP and Windows 7, is supplied for control of the modules and real-time display of force-extension curve. It is also possible with optional software and a video capture card to display a TV image of the sample on your PC screen and save/recall images of the sample under test.

PCspecification–minimumrequirements• Processor: Dual Core 2.0 GHz or higher. • RAM: 2.0 GB or higher. • Operating system: Windows XP with SP.3.0

Windows 7 (32bit or 64bit versions) Home Premium, Business or Ultimate

• Hard drive space: 500MB or higher.


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WARNING

Before running unattended, extended tests ensure that windows automatic updates are turned off.

If the PC restarts unexpectedly during extended tests, data may be lost.

Refer to your PC user guide for instructions on turning off automatic updates

ThewarningbuzzerThe microtest electronics is fitted with a warning buzzer that will sound under the following conditions:

1. The loadcell reading is over-range or under-range. 2. The extensiometer reading is out of range. 3. The stage is not connected correctly.

The correct start-up procedure is to switch on the electronics first, and then start the software. The warning buzzer may sound when the electronics is first switched on because it has not yet been configured by the software.

When the stage is configured correctly and operating within limits, the buzzer will not sound.

If the buzzer sounds during operation the fault condition should be indentified and rectified before continuing.

If the loadcell is reading is showing ‘Under-range’ or ‘Over-range’ without a load being applied, check that the zero-offset slider has been set correctly. See page 33 for further instruction.

If the extensiometer reading is out of range and your stage is fitted with a digital extensometer, ensure that this has been set up correctly using the “displacement” menu item on page 35. If your system is fitted with a non-digital extensometer, then this indicates that the stage has moved past the limit of travel. Use the software controls (goto, jog, , >>--


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The above conditions can also be caused if the connector marked ‘Microtest Module’ is not firmly connected to the rear of the electronics chassis. Ensure that this connector is fully mated and that the thumb screws are firmly tightened.

The electronics should not be left switched on for extended periods without having the software running.

Installation

InstallingthemoduleintoanSEM

The supplied module, when used in an SEM chamber, will be supplied with a port plate adaptor to fit your specific SEM which should be installed in the required location. The port plate has a fifteen way hermetically sealed feed through connector which is used to feed power to the module and data to the PC.

A mounting adaptor to fit your SEM stage will also be supplied. These vary according to the type of stage but typically either slide or screw onto the stage.

The module is fitted with a cable terminated in a 15-way socket, which plugs into the feed through connector on the inside of the port plate. The supplied cable then connects from the outside of the port plate to the 15-way connector on the MICROTEST control unit.

As with all computer peripherals, it is essential to switch off power before inserting or removing connectors.

InstallingthemodulefornonSEMuseIf you are not using the module in an SEM chamber then there may be an additional mounting plate, as specified at time of ordering. Otherwise the module will sit on the bench or on top of your existing optical microscope stage. The cable attached to the module should be connected to the 15-way connector on the MICROTEST control unit.


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Connectingthesystem

CAUTION! Turn off and disconnect power to your computer and any attached devices before inserting or removing any connectors. See drawing below:

Connect all cabling as shown above. Be sure to connect the MICROTEST cable (15 pin) to the correct socket on the control unit rear panel, and ensure the module is connected at the other end of the cable.

Select the relevant loadcell rating using the loadcell selection switch (if fitted.)

Switch on the power to the control unit and other peripherals, and then switch on the power to the computer.

You are now ready to install the software, see the next page. �

TO COMMS PORT ON PC OR USB

MAINS SUPPLY CABLE

MICROTEST MODULE INTERFACE CABLE

PLUG B

FEEDTHROUGH FLANGE ASSEMBLY

SIDE OF CHAMBER

PLUG A

MICROTEST MODULE INTERFACE CABLE

MICROTEST MODULE

NOTE: IF FEEDTHROUGH FLANGE IS NOT TO BE USED, PLUG ‘A’ SHOULD BE CONNECTED DIRECTLY TO PLUG ‘B’


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InstallingtheMicrotestsoftware�

Microtest software is designed to work with Windows XP and Windows 7.

Microtest software is supplied on a single CD-ROM.

Softwareinstallation1. Insert the CD into the appropriate drive.

2. If running Windows 7, an autoplay window may appear as shown below; click on

3. If the installation does not start automatically, then follow the procedure below:

a. Open ‘My Computer’ and navigate to the CD-Rom drive. b. Click on the ‘Setup.bat’ file. (Windows Batch File)


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4. The first window will install the ‘MTComms.DLL’ files. This may require installation of the Microsoft .NET framework V3.5 and the Microsoft Windows installer V3.1 software. These will be installed automatically if required. Follow the on-screen prompts to complete the installation.

Click


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5. Once this step is complete, the installation of the main Microtest software will begin. Accept all defaults by clicking . Follow the on-screen prompts to complete this installation.


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6. During the installation, messages may appear (see below) that mention that a file being copied is in conflict. This is because Microtest uses many common files that are often installed with other software and may already be present. It is safe to ignore these messages. Click , and then continue setup.

7. When the software has successfully installed, the following message will be displayed.

USBdriversWhen the Microtest is first connected to USB, the integrated USB interface will be detected. On most Windows installations, the necessary drivers will be automatically detected and loaded. However, the latest drivers are included on the CD in the folder ‘CDM20602’ should they be required.

Once the drivers have been loaded, the device is ready to use. You will need to setup the correct COM port in the Microtest software using the menu.

Windows will automatically allocate a COM port number to the USB interface. To see which COM port is allocated, open Device Manager in windows and look for an entry in the ‘Ports (COM & LPT)’ section. There should be a device labeled ‘USB Serial port (COMxx)’ and ‘xx’ is the COM port number to be used by Microtest. In the Microtest software, click on the ‘Setup’ menu, then select ‘Port’ and choose the correct COM port from the list.


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TheMicrotestsoftwareLike most Windows applications, you start Microtest by clicking on its icon. Microtest may be started from the Start Menu, from My Computer, from Windows Explorer, or from the Run dialogue box.

When the Microtest program first runs the following parameter file error message may appear:

Click on if this happens. Default settings will then be loaded.

Microtest operating parameters are saved to the parameter file MT_TT.PAR when the program is closed. Window positions and sizes are saved to WINPOS.DEB if this function is enabled. These parameters are then loaded the next time the program is run. These files are located in the ‘C:\Documents and Settings\all Users\Deben’ folder. This folder is accessible to all user privileges so administrator rights should not be required once the software is installed.

All operations are carried out in a multi document interface. Helpful hints are shown in the status bar at the bottom of the main window.

GettingstartedBefore first use, the software must be made aware of the hardware connected. Follow the procedure below to set up your software.

NOTE: ALL SETTINGS CAN BE FOUND ON THE RELEVANT SHEET AT THE REAR OF THIS MANUAL.

PLEASE CONTACT YOU SUPPLIER IF THESE SETTINGS ARE NOT AVAILABLE AS DAMAGE MAY BE CAUSED IF INCORRECT SETTINGS ARE USED.

1. Ensure that all hardware is connected and switched on, and that the software is installed correctly and running.


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2. If the following window appears “Microtest not detected”, ensure that the control unit is switched on. If all appears to be correct, then the COM port selected within the software could be set to the wrong port. Wait until the timeout message appears, click , and then use the ‘Setup – Port’ menu to change to the correct port.

If you still have difficulty setting up the correct com port, go to the system device manager, select , select , and set the com port number to anything between 1 and 16.

If you still experience difficulty, contact your supplier for further instruction.

3. Click on the main Microtest graph window to enable the appropriate menu items.


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4. Click the menu item then menu option to display the following window. The Microtest software allows up to 3 modules to be configured, each with up to 3 loadcells. This window allows the user to easily switch between the different Microtest modules, and select the current module. There is also a tab marked ‘Global’ which will be referred to later (see section ‘ XModule Setup – Global Options X’ on page X24 X)

5. Select the 'Module 1' tab.

6. From the top left drop down menu, select the Microtest module that you are using.

7. From the gearbox drop down menu, select the gearbox that you are using. For some stages only one option will appear.

8. Click on the encoder box to the right of the gearbox menu to select the appropriate option.

9. Under the 'Loadcell 1' title, enter the calibration value for your loadcell. This is normally the full scale load value for your loadcell.

10. Enter the trip level you wish to associate with this loadcell. This level is a user-settable force that describes a limit at which the module will stop. For instance, setting this to 100N on a 300N tensile module will prevent the force from increasing over 100N without affecting the accuracy of the readings. This can be used to provide a safety net for the module and samples in which total fracture is not desired. If a value is not entered, a warning is given and the calibration value is entered as a default.

Scale Factor


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11. Enter the values provided into the Motor P/I boxes, and the Constant Load P/I boxes. See appendix 3 for further information about setting these values.

12. At the bottom of the window, select the extensiometer travel from the drop down box labeled ‘Travel (mm)’.

13. Enter the distance between the jaws when they are in the closed position into the box labeled ‘Minimum (mm)’ below. For example, if your stage is 10-20mm travel, then the extensiometer travel is 10mm, and the minimum position is 10mm. For 20-30mm, the extensiometer value is still 10mm, but the minimum position should be set to 20mm.

14. Your system may be equipped with a digital position measurement system (refer to appendix 4 for details of your system configuration). If the system is digital then click on the tick box labeled ‘Digital’ to select this setting, and enter the value provided for the scale factor.

15. If the position measurement system is analogue then the extensiometer needs to be calibrated for accuracy using the ‘Cal(min)’ and ‘Cal(max)’ values. These calibration values are written in the back page of your manual and are also printed onto the side of the extensiometer itself. It is imperative that these options are set correctly as they determine multiple safety and accuracy limits used in the software.

16. Repeat steps 9 and 10 above for extra loadcells, or steps 5-15 above for extra modules.

17. To activate the settings for a particular module/loadcell combination, simply switch tabs to locate the appropriate module from the module tabs and then click the 'Select' button next to the loadcell you wish to use. Then click 'Apply', followed by 'OK’.

18. When using a digital position measurement system, it is important to set the current position in the software. See page 35 for details on how to do this.


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Quickstarttestprocedures

Below is a list of procedures which should be followed until you are happy that you understand all of the operating parameters.

RunabasictensiletestThis applies to tensile/compression stages only.

1. Check all cables are connected (page X4 X)

2. Switch on the computer and start the MICROTEST software.

3. Check that Setup parameters are correct for your module (page X11 X)

4. If the mode is shown as ‘Compression’ then click on to set the system to tensile mode (page X25 X)

5. Check that the correct loadcell is selected from front panel switch if fitted.

6. Set the sampletime (page X28 X) and motorspeed (page X28 X). For highly elastic samples, use a longer sampletime and a faster motor speed. For brittle samples, use a slow motorspeed and a fast samplerate (100mS).

7. Set the gain if required (page X29 X)

8. Set the loadcell zero offset so that force reads zero N (page X33 X).

9. Move the module jaws so that sample can be inserted. For tensile stages, this normally means clicking on ‘Close jaws’ to move them together as far as possible (pages X19 X and X33 X).

(See separate manual appendix for sample loading procedure.)

10. Insert the sample and tighten clamps. Observe the force reading during this procedure (especially with low force loadcells) to ensure that the force does not go overrange or underrange. Refer to the warning notes for loadcells below approximately 100N as these are easily damaged by rough handling (page X37 X).

11. Click on and observe stress strain curve on the display (page X20 X).

12. Press stop when the test is complete (page X20 X).

13. Enter sample details (page X25 X).

14. Save file to disk (page X23 X).

The test is now complete.


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Runacompressiontest

This applies to tensile/compression stages only.

1. Check all cables are connected (page X4 X)


3. Check that the Setup parameters are correct for your module (page X11 X)

4. If the mode is shown as ‘Tensile’ then click on to set the system to compression mode (page X25 X)

5. Check that the correct loadcell is selected from the front panel switch if fitted.

6. Set the sampletime (page X28 X) and motorspeed (page X28 X). For highly elastic samples, use a longer sampletime and a faster motor speed. For brittle samples, use a slow motorspeed and a fast samplerate (100mS).

7. Set the gain if required (page X29 X)

8. Set the loadcell zero offset so that force reads zero N (page X33 X).

9. Move the module jaws so that sample can be inserted. This normally means clicking on ‘Close jaws’ to move them together as far as possible (pages X19 X and X33 X).

(See separate manual appendix for sample loading procedures.)

10. Insert the sample and tighten clamps. Observe the force reading during this procedure (especially with low force loadcells) to ensure that the force does not go overrange or underrange. Refer to the warning notes for loadcells below approximately 100N as these are easily damaged by rough handling (page X37 X)

11. Click on start motor and observe the stress strain curve on the display (page X20 X).

12. Press when the test is complete (page X20 X).

13. Enter sample details (page X25 X).

14. Save file to disk (page X23 X).

The test is now complete.


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Runabasicverticalbendingtest

This applies to vertical bending modules only.

1. Check all cables are connected (page 4)


3. Check that the Setup parameters are correct for your module (page 11)

4. Check that the correct loadcell is selected from front panel switch if fitted.

5. Set the sampletime (page 28) and motorspeed (page 28). For highly elastic samples, use a longer sampletime and a faster motor speed. For brittle samples, use a slow motorspeed and a fast samplerate (100mS).

6. Set the gain if required (page 29)

7. Set the loadcell zero offset so that force reads zero N (page 33).

8. Move the module jaws so that sample can be inserted. Use the ‘UP’ and ‘DOWN’ buttons in the main software window to position the jaws.

9. Insert the sample. Observe the force reading during this procedure (especially with low force loadcells) to ensure that the force does not go overrange or underrange. Refer to the warning notes for loadcells below approximately 100N as these are easily damaged by rough handling (page 37).

10. Click on and observe the stress strain curve on the display (page 20).

11. Press when the test is complete (page 20).

12. Enter sample details (page 25).

13. Save file to disk (page 23).

14. The test is now complete.


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SoftwareOperation

ControlmenuThe main functions of the modules are controlled from the left-hand control menu as shown below. Menus are the same for all modules except for the motor control buttons that indicate ‘raise/lower jaws’ for the three point bender and ‘open/close jaws’ for the tensile and compression testers.

Datareadoutdisplays

Module status is displayed above the acquisition area and gives a real-time display of mode, force, extension, elapsed time, start position and the current absolute position.

Force indication displays instantaneous force, the display will indicate underrange or overrange if the force is outside the scaled range.

Extension is the real distance moved during a test, pressing the ‘Clear data’ button before starting a test will clear extension back to zero.

Elapsed time is the actual time in seconds from when the test was started. Pressing the ‘Clear data’ button before starting a test will clear the elapsed time reading back to zero.

Start position shows the position at which the last test was started. Again, pressing ‘Clear data’ will set this value to the current absolute position.

Absolute position is the physical distance between the jaws. This is the sum of the start position and the current extension.


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Simplemotoroperation

Motor functions are used to position the jaws/sample clamp so that samples can be inserted and to stop the motor/acquisition cycle.

Note that the above screenshot shows a tensile/compression stage with the motor stopped. The disabled functions become active when the motor is running. Also, if you are using a vertical bending stage (not 3 / 4 point horizontal clamps) then ‘Close jaws’ will change to ‘Up’ and ‘Open jaws’ will change to ‘Down’.

At any time, clicking the red STOP button will stop the stage moving immediately.

Clicking ‘Close jaws’ will move the stage until the jaws are as close together as possible. This should be done before loading a sample for a tensile test as it allows the full range of the stage to be available for the test.

Clicking ‘Open jaws’ will similarly move the jaws as far apart as possible. This should be done before fitting a sample for a compression test.

Note: If the force goes overrange or underrange during these moves, the motor will be stopped automatically.

AdditionalnotesforverticalbendingstagesThese buttons operate in a similar manner for vertical bending stages and the sample clamp needs to be positioned so that the sample can be clamped correctly. Position of the sample clamp will depend on sample size.

Drives the sample clamp up

Halts movement at any time

Drives the sample clamp down

Drive the sample clamp up so that the sample will slide between the jaws. Then drive the clamp down until it is just above the sample. The sample is now ready to be tested.


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StartMotor

Starts the motor and data acquisition. Click on ‘Start Motor’ to commence a test run. The motor will start and the force, extension and elapsed time will be displayed.

A maximum of 256000 points per run can be recorded. When 500 points have been recorded the horizontal scale will automatically change to 1000 points. Likewise at 1000 points it will re-scale to 2000 points and at 2000 points it will re-scale to 4000 points etc.

When the maximum force of the loadcell, or the user preset trip level, is reached, the motor will stop automatically and a message will be displayed.

StopMotor

Stops the motor but allows data acquisition to continue, allowing relaxation of the sample to be monitored. To continue recording data click on ‘Start Motor’ again.

ConstantLoad

This button is only enabled while the motor is running. Pressing this will start the constant load mode. In this mode, the Microtest software will attempt to maintain the current load on the sample for an indefinite period. The motor will run for short periods in both directions as necessary.

If the 'Limit motor speed' global setting has been set, the motor speed will not exceed that which was current when the ‘Constant Load’ mode was initiated.

A prompt will appear on the graph to indicate that this mode is active.

It may not always be possible to maintain a constant load in cases where the sample exhibits high deformation, or is in the breaking transition.

Warning! Breaking characteristics will be changed, as the module will attempt to maintain the decreasing force found during fracture.


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RampLoad

This feature aims to exert a steadily increasing (or decreasing) force upon the sample. The mode is invoked by clicking on the ‘Ramp Load’ button on the motor control panel. This then brings up a dialogue box, like the one below, in which the user can enter the

rate of change of load on the sample. This value is entered in N/min and can range from 1N/min up to the maximum value of the loadcell used. If this value is positive, the force increases with time. If it is negative, the force decreases. Clicking on ‘OK’ activates the mode. A status box shows the current force, the target force, and the error. If the force reaches maximum, or zero, the module is stopped. The module can be stopped at any time by clicking ‘Stop’ or the ‘Ramp Load’ button.

Cleardata

This clears the current data from the acquisition display area and resets the extension reading to zero. The Start position will also be updated to match the current Absolute position.


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GotofunctionsA major new feature for Version 6 software is the introduction of ‘Goto’ movements for the stage.

You can select to move to either a specific force, absolute position, extension or for a specific duration. These target values can be above or below the current equivalent value (except for time moves) which means that the stage will move in either direction to achieve the requested result whilst still recording data. All Goto movements are carried out at the current specified motor speed.

To perform a Goto function, simply select the desired units from the top four items (N, absolute, extension, time) and then enter the target value into the box above. Finally, click ‘Go to’ and the stage will move accordingly. If the requested target value is unachievable, a message will be displayed. Pressing the red ‘STOP’ button at any time will abort the current move.

There are also five more options below which allow various actions to be performed once the target value has been reached.

StopWhen the target is reached, the motor and data acquisition will stop. This is equivalent to pressing the red ‘STOP’ button.

MeasureWhen the target is reached, the motor will be stopped but acquisition will continue. This is equivalent to pressing the ‘Stop motor’ button.

ConstantloadWhen the target is reached, the software will automatically switch to constant load mode as described above.

StepIf this action is selected then the adjacent ‘Set’ button must be used to enter a value before clicking Goto. The step value can be positive or negative and this allows the force or position to be moved in specified steps. The motor and acquisition are stopped after each movement. This allows a complete test to be performed in a number of discrete steps which enables images or measurements to be taken as required. Clicking ‘Goto’ will move to the next step.

CyclictestIf this action is selected then the adjacent ‘Set’ button must be used to enter the desired values for the cyclic test before the ‘Goto’ button is clicked. As soon as the target is reached during the goto move, a cyclic test will automatically start.

See XCyclic Test X on page X29 X for more information regarding setting up a cyclic test.


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SoftwaremenuitemsVarious menus are available to enter parameters and Setup the Microtest software prior to running a test. These menus are as follows: File, Setup, Xscale, Sampletime, MotorSpeed, Gain, Tools, Video, View and About. The entire menu bar is only shown when the Microtest main window is selected. At other times a small selection of the available commands may be shown. Click on the main Microtest window to view the full menu.

File

OpenThis displays the standard Windows ‘open’ dialog box. From here a previous data file may be loaded and viewed.

SaveThis displays the standard Windows ‘save’ dialogue box. From here the current data set may be saved as either a ‘.MTR’ file or a standard comma separated variable ‘.CSV’ file. The data set is saved to disk as an ascii text file with comma column separation. This file may then be opened in a spreadsheet package such as Microsoft Excel.

FilestreamingSelecting this menu item will allow you to stream live data from the test to either a temporary text file, or directly into Excel if it is installed on your PC. This feature can be especially useful if you are expecting to run a very long test as all test data is held in the PC memory until you save the data. This can make the data vulnerable to PC crashes, so saving to a temporary file can help safeguard against this. Depending on your PC specification, there may be slight performance degradation, especially at faster sample rates.

ExportGraphasBitmapThis option will allow the user to save the graph as a bitmap file. This allows easy integration of data into reports. The size of the graph window dictates the size of the saved file; i.e. a large display window will produce a large high-resolution file. Only the graph area is saved, along with any text on the graph at the time. Cursors are not saved in the bitmap.


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CopygraphtoclipboardThis copies this current graph to the clipboard.

ExitCloses the program down and saves all window sizes and positions to the WINPOS.DEB file and all Setup parameters to the MT_TT.PAR file.

Setup

ModuleSetupThis window allows the selection and definition of many module and loadcell parameters. This allows users with multiple modules and/or loadcells to save the settings separately for each combination.

NOTE: When using horizontal 3 or 4 point bending clamps on a tensile tester, do not select the bending class as this applies only to vertical bending modules.

The general use of this window has been described in the section 'Setting up your software', in the section ‘XGetting started X’ on page X11 X.

ModuleSetup–GlobalOptions


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There are two global settings that can be set using this tab.

The first is for use during automated module movement sequences and allows control over the maximum speed allowed by the module. If the 'Limit motor speed' box is ticked then the module will only run as fast as the current motor speed setting. This can be useful when testing brittle or delicate samples, as it prevents the rate of force increase/decrease from exceeding safe limits. It does however mean that under some circumstances the module may not be able to move fast enough to keep up with specified target values.

The other option allows the position and size of many of the main windows to be saved and recalled when the software is next started.

ModeIf you have a tensile tester you may select either tensile or compression mode for your test. Changing this setting will clear any existing data and you will need to reset the zero offset of the loadcell. See XSet Zero X on page X32 X for information about setting the offset.

ScreenThe screen options change the way data is displayed on the screen. Options are dot, line, markers and information.

Dot and line select the way that points are displayed. If dot is selected then each data point is represented by a single dot on the screen. If line is selected then as the dots are plotted on the screen a line is inserted to join up each dot, this gives a much smoother plot that is easier to interpret. It is possible to switch between line and dot after the plot has been made.

If markers are selected a green marker is placed on the plot to show where the motor has been started and a red marker is placed to show where the motor has been stopped. Information will show or hide the commentary text that is applied to the graph when the file is saved. This feature is only available for saved files.

InterfaceTypeThree options are available here. RS232 /USB intelligent interface, EPP printer port, and ISA insertion card. All current systems are fitted with RS232 interfaces. However, if you have an older model, select the appropriate interface here.

PortUse this option if you have connected the Microtest control unit to an RS232 port other than COM1, which is the default setting. The USB connection simulates a COM port, so the correct COM port will still need to be selected when using a USB connection.

SampleDetailsThe sample menu allows sample parameters to be entered. Both rectangular and circular cross sections are supported. These sample parameters are saved with the data and displayed when the file is recalled from disk.


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These parameters are used for calculation of stress/strain so it is important that they are entered correctly if you wish to monitor the stress strain.

This information will also be displayed if the file is transferred to a spreadsheet package.

XscaleX scale is used to change the units of the x-axis. There are four different x scale options supplied.

1. The points scale uses the index number of the sample for the X axis. This index increments by one for each sample taken. The maximum number of data points that can be recorded is 256000.

2. The mm (absolute) scale is the actual distance between the sample jaws when the data point was recorded.

3. The mm (extension) scale is the distance that the sample jaws have moved (since the start of the test, or the last time the 'Clear' button was pressed) at which the data point was recorded.

4. The Seconds scale is the time since the start of the test at which the data point was recorded.

These can be simply split into two groups, force v. time and force v. extension. The force v. extension plots can be very useful for plotting cyclic hysteresis curves, whereas the force v. time plots show trends and instantaneous changes more clearly.

The two plots on the following page show the difference between these two scale types. Both plots are the same dataset, just shown in different ways.

Plots loaded from disk may be viewed in any of the four different x scales.

Data plot using seconds as the units of the x-axis.


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The same data using extension as the units of the x-axis.


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Sampletime

Sample time is the amount of time between each data acquisition and may be set at any value from 100ms to 5 seconds. The chart below shows the possible maximum duration of the test for each sample rate. This is the time taken to fill all 256000 data points.

Sample rate Maximum test duration 100mS 7 hours 6 minutes 200mS 14 hours 13 minutes 500mS 1 day 11 hours

1S 2 days 23 hours 2S 5 days 22 hours 5S 14 days 19 hours

MotorSpeed

The motor speeds shown above are dependent on the type of stage and the gearbox used. Any speed from the menu may be selected.


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Gain

Gain is the vertical scale of the acquisition window. x1 relates to full-scale, so for a load cell of 300N the scale will go from 0N to 300N. If you set the gain to x10 then only the 0 – 30N region will be visible. The gain will automatically scale while the motor is running, so if you start at x10 and the force goes above 30N the gain will change to x5 automatically.

This setting controls an amplifier inside the electronics and is therefore hardware gain. This means that you still retain full 16 bit resolution over the force range shown for each gain setting.

Tools

This menu provides access to the analytical and setup tools provided with the Microtest software.

CyclicTestThis window allows initiation of a cyclic test. Mode is selectable between Force, Absolute position and Extension. Values for maximum and minimum levels are entered directly into the boxes provided. There is no limit to the number of cycles except the recording limit of the graph function, therefore for long tests, a very slow sample time is recommended.


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Once the values have been entered, click the ‘Set’ button. You will then be asked if you want to start the cyclic test immediately. Click ‘Yes’ to do so.

The motor will now start moving until the ‘Maximum’ point is reached. Upon reaching this point, the motor will be stopped, and the system will then wait for the number of seconds as specified in the ‘Set hold time’ box. During this pause, the data will continue to be recorded and this is useful for measuring relaxation in the sample. Once the hold time is reached, the motor will move to the ‘Minimum’ setting. Upon reaching this point, the system will pause once again. This procedure will repeat itself for the number of times as specified in the ‘Number of cycles’ box.

The current phase of the cyclic test will be shown in red at the top of the graph window.

DisplayforceinlargeformatThere are occasions when the force reading is too small to see easily. For this reason, we have included this window, which displays the current force as shown on the graph window as high contrast, re-sizeable text.

CursorsThis provides the user with a crosshair cursor to allow accurate reading of the graph. The X position is shown in all valid scales, points, seconds, and mm. The force is shown in Newtons.

Dragging the vertical red line across the graph moves the cursor. Right clicking the mouse will bring up the option to pick the maximum point on the graph automatically. Cursors are not saved when the graph is exported as a bitmap image.


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ZoomThis allows the user to examine a particular area of the stress/strain curve in more detail.

Area of interest is indicated on the main graph by a shaded rectangle. This area is the duplicated in detail in a separate window that may be resized and repositioned within the workspace. Buttons are available to zoom in or out of the graph.

The track option is for use during acquisition and it attempts to keep the most recent data point within the zoom window, centered vertically.

During long tests, where the number of data points is relatively high, performance may suffer. It is therefore recommended that this function is used once acquisition of the plot is complete.

Stress/StrainStress and strain are calculated in real time in this window. Stress is expressed in N/mm². Both nominal strain and logarithmic strain are shown. These values are not saved with the graph, but are available when the cursor function is used to examine a saved file. The start span for the strain measurement is entered in this window, however the sample dimensions are read from the ‘Setup – Sample Dimensions’ window as described on page X25 X.


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BreakdetectionFor unattended tests, it can be helpful to stop the system if the sample fractures. This normally causes the measured force to drop below a certain value and this drop can be detected using the ‘Break detection’ function.

Clicking this menu brings up the following dialog box where the desired forces can be entered.

These thresholds are shown on the main graph window by two dashed lines. If these lines are not visible then ensure that break detection is enabled by ticking the box in the lower left corner of the main window.

The lower line shows the force at which a break will be detected, and the upper line shows the value which the force must first pass through to enable break detection. The upper line is the break detection force plus the hysteresis value entered into the dialog box. The purpose of the hysteresis value is to prevent false triggering by any noise that may be present on the force reading, and this value can be set to anything from zero upwards.

The following graphs show the function of the break detection feature. It can be clearly seen how the force must first pass the upper line before break detection at the lower line is fully enabled.

The first is using ‘points’ as the X scale and the second is using Extension. As can be seen, when a break is detected the motor is stopped and a message is displayed.

The point at which the break was detected is also shown on the graph in the appropriate units.


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SetZero

Before inserting a sample the loadcell amplifier zero offset must be set and this can be done manually or automatically. The zero offset function is carried out in hardware using a precision D-A converter.

Zero offset is found in the Tools menu.

Auto will automatically set the zero offset to zero, it may then be necessary to slightly adjust the position manually to obtain an optimum reading. Do this by sliding the bar right or left, attempting to make the force reading, as close to zero as possible.

When you insert the sample and tighten the clamps the force may change slightly because the sample is now under stress. This could be a positive or negative stress so the reading could be positive or negative. Since the loadcell zero was set with no sample fitted, the reading should now be showing the true force being applied to the sample.

Jogposition

This allows fine manual positioning of the stage motor. There are four speed range buttons along the bottom of the window (Fast, Medium, Slow and Very Slow) and a large slider above.

To move the motor, click and hold the grey button in the middle of the slider and move it left to move the jaws together or right to move the jaws apart. If the mouse button is released at any point the slider will return to the central position and the motor will stop.

This function can be particularly useful if you use a frame to hold your sample and need to position the Microtest jaws carefully to allow fitment.


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View

Microtest software operates in a multi window environment. Since it is possible that a window may become hidden behind another window, the view menu keeps a track of all the open windows and will allow any of them to be pulled to the front at any time. Right clicking on the dark grey background will also provide this menu. If open windows are placed at the edge of the screen, then scroll bars will appear to allow the user to gain access to them. In this way it is possible to ‘store’ windows off screen to eliminate clutter.

If all windows are closed the only available option is to open the main Microtest window, this will allow reopening of all of the other windows.

About

About

This shows the version of the software and associated DLLs along with the address of our website.

VersionhistoryThis contains detailed information about any changes that have been made to the software for the current release.

OpenPDFmanualClicking this menu item will open a PDF version of this manual on your desktop for easy reference.


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DisplacementIf the system is set up to use digital position measurement, then this menu item will be visible.

SetcurrentpositionThis allows the current absolute position of the stage to be entered into the software. For tensile stages this is the distance between the jaw faces.

For vertical bending systems, see the appendix attached for the absolute position when the jaws are at the upper limit.Settingtheabsoluteposition

1. Remove the sample.

2. For tensile stages, click ‘>>-


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If this message appears then the loadcell reading will need to be adjusted temporarily to allow the stage to reach the upper hardware limit as intended. To do this, adjust the loadcell zero offset to give a force reading of a few Newtons, and then continue this setup procedure from step 2.

3. When the stage reaches the hardware limit, the motor will stop. Click on the main software window.

4. Click and and enter the actual distance between the jaws. This is the extensiometer minimum distance (see Appendix 4). It is recommended to physically measure the distance between the jaws to confirm this value

5. The absolute position is now set.


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Mountingasample�This procedure is for tensile stages. For vertical bending stages, refer to the vertical bending stage appendix supplied with your system. Samples should be mounted to ensure that the jaws can be expanded far enough to complete the test. For tensile tests, the jaws should be moved as close together as possible using the ‘Close jaws’ button. For compression tests, the jaws should be moved as far apart as possible using the ‘Open jaws’ button. Standard stages have a travel of 10mm that is limited at each end of travel by a microswitch or software limits.

To accommodate larger samples or to use the module with an optical microscope where the lens needs to be very close to the sample the Jaws may be extended. The clamp which does not have the load cell fitted may be reversed by removing the four retaining screws, reversing the clamp and then doing up the screws again. This will increase viewable area by 15mm.

If you have the optional horizontal three point bending clamps for the tensile tester please see the separate installation instructions which were supplied with your module.

Note: The jaws cannot move together if the force reading is 'Underrange'. This is to prevent damage to the module and/or the sample.

DemomodeIf no Microtest system is detected when the software is started then the following message appears.


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While this message is on screen, you can click on ‘Enter demo mode’. This starts the software normally but shows an extra window which can be used to simulate the Microtest for training and demonstration purposes.

This window has two main modes of operation – Interactive and manual. The default is Interactive.

The sliders allow you to control the force and extension values and set them to any point within the valid range for the selected stage. In Interactive mode, these sliders will react to most functions such as start/stop motor, cyclic test etc which allows you to explore each function of the Microtest software with no hardware connected.

There is a value for ‘Noise’ which allows a degree of random variation to be superimposed on the force and extension values. This can be varied from no effect at all to almost truly random values as desired.

APPENDIX1–KeyboardShortcuts Shows the large format Force window

Copies the graph to the clipboard

Open the auto zero offset window

Toggle the zoom window

Enables/disables the cursors

APPENDIX2–DatafilesWhen data is saved to a file, or streamed to a file or Excel, a complete set of data is recorded. Along with information regarding force and measurement, there are columns that store data relating to the test such as samplerate and motorspeed.

Point, Elongation, Force, Position, Code, Samplerate, Motorspeed

.5, .021, 0.39, .0216, 2, 500, 4.0 mm/min

1.0, .107, 1.98, .1076, 0, 500, 4.0 mm/min

1.5, .197, 3.62, .1971, 0, 500, 4.0 mm/min


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In addition to these, there is a column called ‘Code’ which records when certain events occur within the system as described below.

Code Event 1 Motor start 2 Motor stop 3 Start of a tensile cycle during a cyclic test 4 Start of a compression cycle during a cyclic test 5 Constant load start

99 Motor stall

During a test, motor start and stop events are also indicated on the graph by vertical green and red markers. A quick reference of these event codes is available in the Microtest software via the menu.

APPENDIX3–P/IvaluesThe default P and I values for the Microtest system are shown in Appendix 4. These values are used to configure two control loops within the software, one to control the motor speed and one to control the constant load routines. The P and I values for the motor speed control loop should not normally need to be adjusted from these default values. The P and I values for the constant load may need to be modified to suit different test samples. Many different techniques for tuning PI loops exist, but only the relatively simple ‘estimate and check’ method will be discussed here. Each control loop has two main input signals. The first is the requested value, and the second is the measured value. For instance, in the constant load control loop, the first value is the target force we require, and the second is the current force as measured by the loadcell. The difference between these two values is the ‘error’ and the ‘P’ value determines how the control loop will react to this error. Small values of ‘P’ will cause the loop to react slowly to large errors, and large values will cause it to react more quickly. However, slow reactions are undesirable, and large values may cause the system to oscillate. To set ‘P’, first set ‘I’ to zero. Command the system to hold a force using the constant load mode and wait until the system stabilizes. If the force is oscillating above and below the target force then the P value is probably too high. Enter a lower value and click ‘Send PID values’ until the oscillations cease. If the force applied to the sample never reaches the target force then the P value is probably too low. Enter a high value for Motor P and click ‘Send PID values’. The aim is to have the P values set as high as possible so that the system reacts quickly, but low enough to ensure that it does not oscillate. Once this is set, you will probably notice that the applied force is always slightly below the target force, and that it may drift away from the target force over time. The control loop will monitor small errors and accumulate them over time until the total error becomes large enough to cause the system to respond and correct the error. The ‘I’ value determines how the control loop will react to these small errors. As a guide, the ‘I’ value should be


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APPENDIX4‐SystemsettingsSystem parameters

Serial number Voltage Interface type Firmware revision Software revision Microscope


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Appendix5–ChineseRoHSDeclaration零件项目(名称) (Component Name)

有毒有害物质或元素(Hazardous Substances or Elements)

铅 Lead (Pb)

汞 Mercury (Hg)

镉 Cadmium (Cd)

六价铬 Chromium VI Compounds (Cr6+)

多溴联苯 Poly-brominated Biphenyls (PBB)

多溴二苯醚 Poly-brominated Diphenyl Ethers (PBDE)

Module (Stage) O O O O O O

Controller O O O O O O

Cables O O O O O O

Accessories O O O O O O

O: 表示该有毒有害物质在该部件所有均质材料中的含量均在 SJ/T 11363-2006标准规定的限量要求以下. O: Indicates that this toxic or hazardous substance contained in all of the homogeneous materials for this part is below the limit requirement in SJ/T11363-2006. X: 表示该有毒有害物质至少在该部件的某一均质材料中的含量超出 SJ/T 11363-2006标准规定的限量要求. X: Indicates that this toxic or hazardous substance contained in at least one of thehomogeneous materials used for this part is above the limit requirement in SJ/T11363-2006. 除非另外特别的标注,此标志为针对所涉及产品的环保使用期标志. 此环保使用期限只适用于产品是在产品手册中所规定的条件下工作. The Environmental Protection Use Period (EPUP) for all enclosed products and their parts are per the symbol shown here, unless otherwise marked. The Environmental Protection Use Period is valid only when the product is operated under the conditions defined in the product manual.