vm2__series_viscometer_operators_manual.pdf
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VM2
Viscometer
OPERATING MANUAL
Models covered:- VM2-L, VM2-R, VM2-H.
ASTM D standards 789, 1824, 2196, 2393, 2669, 2983, 4878.
ISO 1652, 255
Sheen instruments VM2
Issue D 2007
Page 2
0. Contents
0. Contents .......................................................................................................................2
2. Important rheological notes ...........................................................................................3
3. Basic rules for correct measurements ............................................................................3
1.
Presenting the VM2 Viscometer .............................................................................6
1.1
Delivery .................................................................................................................................... 6
1.2
Environmental conditions .................................................................................................... 6
1.3
Maintenance ............................................................................................................................ 7
Setting up the equipment ................................................................................................................ 8
1.4
Description of the instrument.............................................................................................. 9
1.5
The keyboard and display ...................................................................................................10
4. Main menu ...................................................................................................................12
5. Configuration menu .....................................................................................................12
5.1 Configuration main display ..........................................................................................................12
5.2 Changing the language (submenu Language) ...........................................................................13
5.3 Changing the time and date (submenu Clock)...........................................................................13
5.4 Changing the units........................................................................................................................14
5.5.1 Viscosity calibration ...........................................................................................................16
5.5.2 Temperature calibration.....................................................................................................17
5.6 Plotter submenu ...........................................................................................................................18
5.7 RESET submenu..........................................................................................................................19
6. Measurement configuration menu.............................................................................20
6.1 File submenu ................................................................................................................................20
6.2 Plotter submenu ...........................................................................................................................21
6.3 Submenu for selecting the measuring parameters....................................................................21
6.4 Measuring display.........................................................................................................................23
7. Memories menu ...........................................................................................................24
7.1 Option: using a memory...............................................................................................................24
7.2 Option: writing a memory.............................................................................................................25
8. Autotest menu .............................................................................................................25
9. PC connection .............................................................................................................26
10. Accessories ...............................................................................................................27
10. 1. Low viscosity adapters LCP and LCP/B.................................................................................27
10.1.1 Building up .........................................................................................................................28
10.1.2 Taking apart and cleaning...............................................................................................29
10.1.3 Technical specifications of the LCP Adapter ..............................................................29
10.2.1 Building up .........................................................................................................................30
10.2.2. Taking apart and cleaning..............................................................................................31
10.2.3 Technical specifications of the APM.............................................................................31
10.3 HELDAL UNIT - Helix Drive Unit ..............................................................................................32
Table 1 Compatibility model / spindle...........................................................................37
Table 2 Standard spindles selection: VM2 - L................................................................38
Table 3 Special spindles selection: VM2 - L ...................................................................39
Table 4 Adapter LCP with VM2 - L..................................................................................40
Table 5 Standard spindles selection: VM2 - R ...............................................................41
Table 6 Special spindles selection: VM2 - R ..................................................................42
Table 7 Adapter LCP with VM2 - R .................................................................................43
Table 8 Standard spindles selection: VM2 - H ...............................................................44
Table 9 Special spindles selection: VM2 - H ..................................................................45
Table 10 Special HELDAL spindles selection for VM2 - L...............................................46
Table 11 Special HELDAL spindles selection for VM2 - R ..............................................47
Table 12 Special HELDAL spindles selection for VM2 - H ..............................................48
Table 13. Characteristics of the special spindles...........................................................49
Appendix A. ‘Datalogger’ software for the PC. ..............................................................49
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2. Important rheological notes
To get accurate measuring results it is necessary to know the most important rheological
properties of the sample:
Newtonian fluids (e.g. water):
The viscosity of these fluids does not depend on shear rate i.e. at any speed the viscosity
is the same. Only the temperature affects the viscosity, 1 °C temperature change means
up to 10 % of viscosity change.
Time independent non-Newtonian fluids:
At a certain shear rate and temperature the viscosity reading is always the same. There is
no change in viscosity when the sample is held under constant shear rate for a long time.
Changing the shear rate also changes the viscosity.
Shear thinning, pseudoplastic behaviour (e.g. coatings, shampoos): high shear rate
means low viscosity
Shear thickening, dilatant behaviour (e.g. starch dispersions): high shear rate means
high viscosity
Time dependent fluids:
Even under constant shear rate and temperature the fluid shows a change in viscosity
over time.
Thixotropic behaviour (e.g. Ketchup, pastes, crèmes): viscosity decreases in time under
shearing
Rheopectic behaviour (e.g. latex dispersions, surface-active agents): viscosity rises in
time under shearing
Please note that high shear rates could also lead to a warming of the sample, which
could be misinterpreted as a time dependent behaviour.
Also, turbulent flow could lead to falsely high viscosity reading; Turbulence is caused by
too high speed in relation to the sample viscosity.
As with any measurement, in addition to the rheological properties of the sample also
instrument related variables influence the results:
1.
2.
3.
4.
5.
6.
7.
Sample temperature (repeatability should be better than 0.1 °C, 0.2 °F)
Sample container diameter / spindle-chamber geometry
Filling level of container / immersion of spindle
Viscometer model
Spindle used (guard leg attached or not)
Test speed (for non-Newtonian fluids)
Duration of test (for time dependent fluids)
3. Basic rules for correct measurements
These instructions help to get reliable and comparable measurement results.
Keep a record - always take down the following data for each measurement:
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•
•
•
•
•
•
•
•
viscometer model
spindle type
accessory (small sample adapter, low viscosity adapter, helix drive unit) if used
rotational speed
volume or dimensions of sample container
sample temperature
sample preparation procedure (if any)
whether or not the spindle guard was used
Only measurements performed under identical conditions can be compared, therefore it
is very important to know these data.
Check the spindles and use the spindle guard
Check each spindle before using it. Severe corrosion or damages - such as bent shafts that may affect the spindle dimensions can cause an erroneous viscosity reading. It is
recommended to buy a new spindle in case of damage.
The spindle guard (part of the standard supply of all models) influences the measurement
results, especially for the spindles no. 1 and 2. If operating the viscometer without the
guard make a note of this fact in the measurement record.
How to select a spindle and a speed
For tests according to existing specifications or routines use the specified spindle and
speed. Just make sure that the viscometer is the correct model.
If performing a new test the optimum spindle/speed combination is best found by trial and
error.
One should get a display reading between 15 and 95 % of full range of scale.
•
If the reading exceeds the 100 % the viscometer gives an error message
and a warning sound. In that case select a slower speed and/or a smaller
spindle.
•
For readings lower 15 % of full-scale range the viscometer just makes a
warning sound. Select a higher speed and /or a larger spindle.
If the approximate sample viscosity is known, the correct spindle/speed combination can
be determined by using the selection tables in the operator handbook.
When performing multiple tests use the same spindle/speed combination for all tests. For
tests that require measurements at different speeds choose a spindle that permits
readings within the limits (between 15 and 95 % of full scale range) at all desired speeds.
It is recommended to use the Low Viscosity Adapter for exact measurements if the
following applies:
• Viscometer L model, sample viscosity of less than 15 cP
• Viscometer R model, sample viscosity of less than 100 cP
Hint:
Generally the following rule can be applied to NEWTONIAN FLUIDS:
• Increase of RPM
increase of reading accuracy
• Decrease of spindle no.
increase of reading accuracy
(In non-Newtonian fluids the viscosity depends on the shear rate, i.e. the rotational
speed.)
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Select a sample container / sample container correction factor
The inner diameter of the sample container should be 83 mm or larger. The usual vessel
for measurement is a beaker with a filling volume of 600 ml.
Hint:
If using a smaller vessel the viscosity readings will increase (showing an apparently
higher viscosity), especially with the spindles no. 1 and 2.
•
If it is necessary to employ a container different to the specified one, some
correction factors have to be established in order to obtain an exact
measurement.
•
To calculate a correction factor for a range, a spindle and a container, just
measure a substance of known viscosity (at the specified temperature in
the range and using the desired spindle and container) and take down the
viscosity.
The relationship between this measured viscosity and the actual viscosity
of the product is the correction factor for the measurements done with this
spindle in this beaker.
•
•
The readings made from small containers and/or without the spindle guard
can only be used as comparative measurements and not as absolute
measurements of viscosity unless the above mentioned correction factors
are used with every spindle and container.
Sample conditions
The sample fluid should be free from air bubbles. Remove such bubbles by gently
rapping the container on the table or with a vacuum device.
• The sample temperature should be constant and homogenous for the
entire filling volume. After correctly immersing the spindle and guard into
the sample wait for temperature equilibrium of these parts and the sample
before starting measurement. If using a 600 ml beaker it is recommended
to wait at least for 30 minutes. For optimum equilibration let the instrument
turn at the speed you intend to measure at.
• The sample consistency must be homogeneous, too. This applies
especially to samples consisting of two components (e.g. emulsions). By
stirring the sample the components can be kept from separating. The
sample to be measured should not contain particles with a tendency to clot
or settle at the bottom, particles that could be deformed by the shear
stress, be decomposed into smaller particles or be oriented in the flow
stream.
• Samples under test should not be submitted to chemical or physical
changes. Avoid chemical or physical reactions in the sample while testing
it.
Flow conditions
Viscosity measurements should be taken under laminar flow conditions, not under
turbulent ones. Else the turbulent flow will cause false readings, showing a viscosity value
higher than the actual sample viscosity.
The higher the used speed and the lower the sample viscosity, the more this effect will
influence the readings results. If readings with absolute viscosity are required, it is
recommended to use cylindrical geometry spindles (with Small Sample Adapter, Low
Viscosity Adapter or with models L) with which this effect is reduced.
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Laminar flow means that all particle movement happens in layers directed by the
shearing force. It is comparatively easy to predict and the mathematics of the viscometer
base on linear flow conditions.
In turbulent flow the motion of particles is random which is why the flow cannot be
analysed with standard mathematical models and faulty readings occur.
Hint:
The below values serve for orientation of the user. These are the approximate limits
where the sample flow changes from laminar to turbulent. For the indicated spindles
turbulent flow will occur if the speed/viscosity ratio is greater than the below values
(speed in rpm, viscosity in mPa.s or cP).
• L1 spindle:
• R1 spindle:
• Low viscosity adapter:
15mPa.s at 60rpm
100mPa.s at 50rpm
0.85mPa.s at 60rpm
limit: 60/15 = 4 (max.)
limit: 50/100 = 0.5 (max.)
limit: 60/0.85 = 70.6 (max.)
1. Presenting the VM2 Viscometer
1.1 Delivery
1. When you receive the package containing the equipment, check the delivery note and
contents. If you find any damage or discrepancy, notify your local representative or
supplier immediately.
2. Figure 1 shows the position of each component in the transport case. Keep the
transport case in a safe place. If you need to transport the equipment or store it for a
long period of time, always use the transport case, positioning each component as
shown in Figure 1. If a component is damaged as a result of transporting the
equipment badly, this is not covered by the manufacturer’s guarantee.
3. Check that the model delivered is the one you ordered.
4. Read the instructions for use very carefully.
5. All modifications to the equipment, removal of parts or lack of maintenance to any
component is against the directive for use 89/655/CEE and the manufacturer is
therefore no longer responsible for any damage, which may occur as a result.
1.2 Environmental conditions
•
•
•
•
•
•
•
Internal use
Altitude to 2000 meters
Room temperature: from +5 to 40ºC
Maximum relative humidity 80% up to 31ºC, lowering to 50% relative humidity
at 40ºC.
Electrical supply fluctuations cannot exceed ±10% nominal tension
Installation category II
Pollution level II
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It should be noted that due to the precision manufacture of this instrument every
care has been taken to ensure total reliability in use, however, contaminated
conditions or corrosive atmospheres must be avoided.
1.3 Maintenance
Due to the precision manufacture this instrument and depending on the frequency of use
and environmental conditions, the Viscometer may require preventative maintenance
checks/cleaning and calibration. In this case, contact Sheen Instruments or your local
supplier.
Sheen Instruments,
2 Gatton Park Business Centre,
Wells Place,
Redhill,
Surrey,
U.K.
Tel +44 (0)1737 649300
Fax +44 (0)1737 649301
Email info@sheeninstruments.comice
Regular maintenance is important. We recommend checking your viscometer annually.
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Setting up the equipment
•
Remove all parts from the carrying case. Refer to the below figure.
•
Make sure the feet (B) are fixed to the Y shaped stand (A).
•
Mount the vertical holding rod (C) with the fixing nut (D) in the stand (A).
•
Mount the block (F) on the vertical holding rod and tighten the nut of the block.
Note:
The following procedure must be done carefully to avoid any damage to the
viscometer’s shaft.
•
Insert the small horizontal rod of the measuring head (E) in the boss head of the block
(F).
(Fig. 1)
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1.4 Description of the instrument
Front view of the instrument (Fig. 3).
1
6
7
2
8
3
4
9
5
1.
3.
5.
7.
9.
Softkeys
Toothed Rod
Feet for levelling
Power Switch (at rear)
Spindle
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2.
4.
6.
8.
Spindle protector
Stand Base
Display (LCD)
Temperature Probe
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Rear view of the instrument (Fig. 4).
2
3
1
4
5
1. Type plate with the serial number (see Fig. 5)
2. Power switch and connector for the power supply cable
3. RS232 interface for connecting a PC
4. I2C interface for connecting a temperature controller
5. Interface for connecting a plotter (i.e. pen recorder)
Type plate showing the serial number (Fig. 5)
3
1
2
4
1.
2.
3.
4.
Viscometer model
Viscometer code
Serial number
Supply voltage, frequency and power consumption
1.5 The keyboard and display
Before starting up the instrument, take some time to familiarize yourself with the features.
The instrument has 6 softkeys (see position 1, Fig. 3) and a 4-line text display (see
position 6, Fig. 3). The softkeys and display are located on the front of the instrument.
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The display shows the operation carried out as well as the measurements performed by
the instrument. Using the keyboard and display, the user can move freely within all menu
levels, select different options and create configurations for the viscosity measurements.
The different menu options are described in detail in later chapters of this handbook.
Each of the 6 softkeys has a basic function, which is explained below:
Softkey
‘∆’
‘∇’
‘TAB’
‘ENTER’
‘QUIT’
‘ON’
Function
Go to the previous option / increase a value
Go to the next option / decrease a value
Change the input field in the configurations
Accept or select
Cancel or leave
Stop/start the motor during measurements /
access to special functions.
In some menu options, a different function may be assigned to a softkey.
The following sections describe the functions of the softkeys in more detail.
Start up
Switch on the instrument with the power switch at the rear. If the instrument does not
start:
•
Ensure that the power cable is connected to the VM2 (see position 2, Fig. 4) and
the power supply.
When the instrument works, the following message appears on the display:
Sheen Inst
V.1.0
VM2
English
This start display shows the version and model of the instrument and the language
selected. After a few seconds, the start display disappears and the instrument main menu
is shown as below.
> Measurement
Test Profiles
Auto test
Instrument Setup
The instrument is preset to English language, and cP as the unit of viscosity.
These parameters can be changed to suit the user. This is described in the following
sections.
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4. Main menu
The instrument is equipped with a system of menus, which allow the user to control the
instrument simply and rapidly. The basic actions in the menus are:
• Move through the options (softkeys ‘∆’ and ‘∇’),
• Select an option (softkey ‘ENTER’)
• Move to the previous menu (softkey 'QUIT').
The main menu appears after the start display after switching on the instrument.
It contains the menus for creating a measurement profile (‘Measurement’)
For calling or storing a measurement profile (‘Test Profiles’), the Autotest function
(‘Autotest’) and the menu for configuring the equipment (‘Instrument Setup’). The display
shows:
> Measurement
Test Profiles
Auto Test
Instrument Setup
The option ‘Measurement ’ is selected and highlighted by default. You can move up and
down in the menu using the ‘∆’ and ‘∇’ softkeys. Press ENTER to select an option. This
takes you to the appropriate submenu.
When using the instrument for the first time, it is advisable to first proceed to the option
‘Instrument Setup’ to establish values for certain parameters, such as language and
measuring units. To get to this submenu, press the ‘∇’ softkey 3 times until the option
‘Instrument Setup’ is marked with an arrow ‘→’. Press ENTER to accept this selection.
5. Configuration menu
5.1 Configuration main display
The ‘Instrument Setup’ menu contains some functions, which change the status, and/or
function of the instrument. When this option is selected the following menu appears:
Instrument Setup
>Language
Adjust
Clock
Plotter
Units
Reset….
Move up and down through the menu using the ‘∆’ and ‘∇’ softkeys and select a
submenu by pressing ENTER. In this submenu you can change the language, the time
and date, choose the measuring units (see sections 3.2 to 3.4), select the spindle type
and Poise value, perform a calibration on the instrument, configure the plotter and
initialise the instrument. The language, measuring units and main control functions should
be selected and entered by the user before starting work with the instrument so it will
perform correctly during use.
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Pressing the QUIT softkey will stop the selection and return you to the main menu. The
following sections describe the submenus of the ‘Instrument Setup’ menu.
5.2 Changing the language (submenu Language)
The first option in the ‘Instrument Setup’ menu is the ‘Language’ option (marked with >).
The languages can be selected and displayed by using the ‘∆’ and ‘∇’ softkeys:
To change the language, press ENTER.
The following display appears:
Select a language:
English
Languages available: English
French
German
Spanish
Portuguese
Italian
Japanese
Catalan
Dutch
With the desired language selected, press ENTER. The language is changed
automatically in all the menus. To leave the menu without changing the language, press
QUIT.
5.3 Changing the time and date (submenu Clock)
When you select the option ‘Clock’ in the ‘Instrument Setup’ menu the following display
appears:
Time
hh:mm:ss
Current: 00:00:00
New:
00:00:00
The third line (Actual) is the time set for the instrument. This line cannot be changed. The
fourth line (New) can be changed to the desired time. The first digit corresponding to the
hour (hh) in the “New” line blinks. Using the ‘TAB’ and ‘ENTER’ softkeys, the selection
made will be highlighted, the value of this digit can be changed using the ‘∆’ and ‘∇’
softkeys to increase or decrease the value.
To change the value of the second digit, (mm) press TAB. The blinking square moves
along to the second digit, which can be changed as above by pressing ‘ENTER’ and
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using the ‘∆’ and ‘∇’ softkeys to increase or decrease the value of the selected digit.
Press ENTER to confirm the value.
To move to the second’s field (ss), use the TAB softkey. Press ‘ENTER’ and the first digit
blinks when selected. Proceed as above.
Pressing QUIT aborts the change and restores the previous value set in the field.
After the desired hours, minutes and seconds have been set, confirm the new time by
pressing the ‘ON’ softkey. If you do not wish to change the time, simply press ON. The
display for changing the date appears. The steps for changing the date are the same as
described above for changing the time. Confirm the changes in the date by pressing the
’ON’ softkey. This returns you to the main menu; Pressing QUIT aborts the changes and
restores the previous value.
5.4 Changing the units
The VM2 allows you to change the measuring units for viscosity and temperature.
Selection options for the dynamic viscosity are: SI units (Pa·s or mPa·s) or CGS units
(Poise or centiPoise). (The measuring units for kinematic viscosity cannot be changed:
these are given in cSt or Stoke and are used when the user enters a density value
greater or less than 1 for the sample). The options for the temperature are Centigrade
(ºC) and Fahrenheit (ºF).
To change the measuring units, select the submenu ‘Units’ using the ‘∆’ and ‘∇’ softkeys
and press Enter. The following display appears:
>
Viscosity
Temperature
Select ‘Viscosity’ or ‘Temperature’ using the ‘∆’ and ‘∇’ softkeys and press ENTER. If you
select ‘Viscosity’, the following display appears:
Select the units
CP/P (cgs)
Use the ‘∆’ and ‘∇’ softkeys to select either SI units or CGS units and then press ENTER.
Pressing the QUIT softkey aborts the selection and restores the previous setting.
Pressing ‘ENTER’ after a selection or aborting a selection returns you to the unit selection
display.
From the unit selection display, select ‘Temperature’ and press ENTER. The following
display appears:
Select the units
ºC
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Choose between degrees Centigrade and degrees Fahrenheit using the ‘∆’ and ‘∇’
softkeys and press ENTER. Pressing QUIT aborts the selection and restores the previous
setting. Pressing ENTER after a selection or aborting a selection returns you to the unit
selection display. Pressing QUIT again returns you to the main configuration display.
5.5 Adjust (Calibration) submenu
This submenu contains the options for recalibrating viscosity and temperature.
IMPORTANT: It must be understood by the user that without the correct equipment,
(temperature controlled water bath, digital thermometer with an accuracy of 0.001°C
and the require calibration oils) the calibration or a re-calibration of the instrument
should not be attempted as all preset calibration data will be overwritten and lost.
The VM2 when purchased has a default calibration which was performed in the
manufacturing process and is stored in the viscometer. Therefore, the instrument
does not need to be calibrated prior to being used for the first time.
However, quality norms recommend recalibrating the instrument once a year.
However it is possible for the user to recalibrate the instrument without returning it
to Sheen instrument or your local agent, but due consideration must be taken to the
information above.
Sheen Instruments is not responsible for measurements
performed after the instrument has been recalibrated by the
user.
CALIBRATION NORMS:
• To perform a viscosity calibration, you need two standard calibration oils and a
thermostatically controlled water bath to keep the calibration oils at a constant
temperature (to within 0.1°C of the temperature recorded for the calibration oil)
• If you do not have this equipment, you will not be able to perform a reliable
calibration, do not proceed further. Sheen Instrument can supply standard oils
and equipment to perform this calibration, please enquire.
• To perform a temperature calibration, there are two options: The first requires a
thermostatically controlled water bath to maintain fluids at 0º and 100º (this can be
supplied by Sheen, Please enquire.) The second option requires a complete
simulator calibration set which simulates the exact function of the PT100 probe,
which is then connected instead of the PT100 probe.
From the ‘Instrument Setup’ menu, select the option ‘Adjust’ and press ENTER. The
following display appears:
>
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Viscosity
Temperature
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5.5.1 Viscosity calibration
Select the ‘Viscosity’ option and press ENTER. The following display appears for L
models:
Spindle L1
v
100.0 cP
And for the R models the display is as follows:
Spindle R1
v
100.0 cP
On entering this display, the field ‘Spindle’ blinks. Use the ‘∆’ and ‘∇’ softkeys to select
the spindle number, Press ENTER to select which spindle should be calibrated. Confirm
the selection of the spindle by pressing ENTER. Pressing QUIT aborts the selection.
The list of spindles which can be calibrated depends on which model of Viscometer you
are using (model L, R or H). The spindles available for each model are listed in the tables
at the rear of this manual.
After selecting the spindle go to the viscosity field (using TAB) and pressing ‘ENTER’ and
using ‘∆’ , ‘∇’ and ‘TAB’ softkeys enter the viscosity of the standard oil used for the
calibration. (the viscosity values are stated on the calibration certificate supplied with the
Sheen calibration oil) Once the value of the standard oil is confirmed by pressing
‘ENTER’, press the ‘ON’ softkey to continue with the calibration process. The following
display appears:
ATTACH THE
SPINDLE
AND
PRESS <ENTER>
After attaching the spindle and pressing ‘ENTER’ the screen will shows:
Delay time:
00h 00m 00s
Enter the length of time to elapse (Delay) between giving the calibration command and
the start of the calibration. This time is usually used to ensure that the spindle and the
sample reach the required constant temperature before the calibration is started. To set
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each time, press the ‘Enter’ key to select each segment, when selected (Hours) the
segment will flash, using the ‘∆’ and ‘∇’ softkeys and the enter key to select each group,
pressing the ‘Tab’ key moves you to the next segment (minutes) and the same procedure
should be followed for the seconds, when this delay time is complete immerse the paddle
into the calibration oil and press the ‘ON’ softkey, this starts a countdown to zero before
the calibration starts.
When the countdown reaches zero, the viscometer begins the calibration sequence.
During the calibration, the following display appears:
Calibrating...
1/11
NOTE: The calibration process takes approx 30 minutes and consideration should
be made for the calibration oil to be maintained at a constant temperature and held
to ±0.1°C of the stated temperature during this calibration, failure to maintain this
requirement will render the instrument inaccurate in subsequent readings.
Once the calibration method is finished, the viscometer displays the linearity error (%).
Pressing ‘ENTER’ to accept it.
Pressing ‘QUIT’ during the calibration process, the calibration stops immediately without
saving any data, and the following screen will be displayed again, to re-start the process
if it is necessary:
>
Viscosity
Temperature
5.5.2 Temperature calibration
Select the ‘Temperature’ option in the ‘Calibration’ submenu and press ENTER. The
following display appears:
Unplug the PT100
probe and connect
the 0°C gauge
press <ENTER>
The display gives instructions on performing the calibration of the temperature probe.
Connect the PT100 simulator (called "0°C gauge") which simulates the parameters
equivalent to a PT100 at 0°C. After connecting the simulator press ENTER. The following
display appears:
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Calibrating...
After a few seconds, a second display appears with the following information:
Replace the 0°C
gauge with the
30°C gauge
press <ENTER>
Now, connect the simulator equivalent to a PT100 at 30°C ("30°C gauge"). After pressing
ENTER the following display appears again:
Calibrating...
After a few seconds, a third display appears with the following information:
Replace the 30°C
gauge with the
100°C gauge.
press <ENTER>
Connect the simulator for 100°C and press ENTER. The display showing “Calibrating...”
appears again. After a few seconds, the main calibration display appears. To return to the
main ‘Instrument Setup’ display, press QUIT.
5.6 Plotter submenu
This menu contains the options for adjusting the plotter (pen recorder). The plotter can
transfer the curve of the viscosity over time onto paper. To use the plotter it is first
necessary to perform a plotter calibration. (Detailed information on using a plotter can be
found in later sections).
NOTE: The plotter is not supplied with the VM2 Viscometer.
Select ‘Plotter’ in the main ‘Configuration’ display and press ENTER. The following
display appears:
Connect the
plotter
and
press <ENTER>
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To continue with the adjustment follow the instructions given in the display. Connect the
plotter to the corresponding interface at the VM2 (position 5, Fig. 3). Press ENTER. The
following display appears:
Adjust the zero
level of
plotter
press <ENTER>
Perform a zero point adjustment for the plotter, varying the position of its offset.
IMPORTANT: Do not manipulate the gain control to make this adjustment. After the zero
point adjustment is completed, press ENTER. The following display appears:
Adjust the full
scale of
plotter
press <ENTER>
Now adjust the full-scale range using the gain control of the plotter.
IMPORTANT: Do not manipulate the control of the offset to adjust the full-scale range.
When the adjustment is finished, press ENTER. This completes the adjustment of the
plotter and returns you to the main ‘Configuration’ display.
5.7 RESET submenu
This submenu contains the RESET options for the instrument. Resetting the instrument
restores the calibrations which were set when the VM2 left the factory, i.e. the original
viscosity and temperature calibrations. In this submenu, the following display appears:
ATTENTION:
Instrument RESET
<ENTER> <QUIT>
If you wish to proceed with the reset, press ENTER. If you do not wish to proceed, press
QUIT. If you decide to continue with the reset, a second display appears asking you to
confirm:
Are you sure?
<ON> <QUIT>
If you press ‘ON’, the factory calibrations are restored and the main ‘Instrument Setup’
display appears. If you press QUIT, the configuration is not changed and the main
‘Instrument Setup’ display appears.
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This is the last submenu within the ‘Configuration’ menu. To return to the main menu,
press QUIT.
6. Measurement configuration menu
The measurement configuration menu gives access to the basic function of the
instrument: viscosity measurement of liquids. In the main menu, select the option
‘Measurement’ and press ENTER. The following display appears:
Output
> File
Plotter
No
No
This display gives you additional options for storing the viscosity and temperature
measurement data. There are three possible destinations for the measurement data:
• Display: The data is shown only on the display. (both ‘File’ and ‘Plotter’ = ‘No’)
• File: When selected to File = ‘Yes’, the file records the measurements for later
transfer to a PC using the program Datalogger (supplied with the VM2 Viscometer
see Appendix A).
• Plotter: When selected to Plotter = ‘yes’, the instrument generates an adequate
voltage at the 9 way output plug to create a curve of viscosity over time on a
paper plotter.
NOTE: The two different output options can either be selected independently or may both
be selected to ‘Yes’ as they are fully capable of transmitting data as shown on the display
to the file and plotter simultaneously.
After choosing the output options (refer to the following sections) press ‘ENTER’ to
proceed with the measuring process. If you wish to abandon the measuring process,
press QUIT in this display.
6.1 File submenu
With the ‘File’ option selected and the ‘ENTER’ softkey pressed, the following display
appears. Using the ‘ENTER’ and ‘TAB’ softkey to highlight and select the h, m, and s for
each of the parameters. This is the display for defining the file output:
File
Start 00h 00m 00s
Stop 00h 00m 00s
Step 00h 00m 00s
There are 3 sections in the display, which are:
• Start time (Start): Time from the start of the test until the obtained values are
actually stored to file.
• End time (Stop): Time from the start of the test until the obtained values stop
being stored to file.
• Time increment (Step): The difference in time between two consecutive values in
the file. If the time difference is fixed to ‘00h 00m 00s’, then all the values
obtained are stored in the archive.
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For example:
If we wish to perform an experiment which takes 3 hours and store the data acquired
between the second and third hour every minute, the setting would be as follows:
File
Start 02h 00m 00s
Stop 03h 00m 00s
Step 00h 01m 00s
To change the values in this display (h, m, s), use the softkeys as previously described
(TAB to change the field, ENTER to edit,)
When the desired values have been entered for the test, press ‘ON’ to confirm this
setting and activate the output into the file. (‘Yes’) Pressing QUIT deactivates the output
into the file.
IMPORTANT: The VM2 can only store one acquired file. When a new file is acquired, the
previous file is deleted. It is therefore recommended to transfer the contents of the file to
a PC using the program ‘Datalogger’ each time a test has been completed (see Appendix
A).
6.2 Plotter submenu
Select the submenu ‘Plotter’ in the outlet selection display using the ‘∆’ and ‘∇’ softkeys
and press ENTER. This is the display for defining the plotter outlet. The following display
appears:
Plotter
Start
Stop
00h 00m 00s
00h 00m 00s
As in the File display, there are options for defining lengths of time. In this case, you
select the start time and the end time. During these set times the plotter outlet (position 5,
Fig. 3) emits a voltage so that the plotter can produce a graphic representation on paper.
Change the values using the softkeys as previously described. Pressing ‘ON’ after setting
the values activates the plotter outlet (‘Yes’). Pressing QUIT deactivates the plotter outlet.
6.3 Submenu for selecting the measuring parameters
When the outlets have been defined, select the measuring parameter submenu from the
measurement menu by pressing ‘ON’. The following display appears:
Output
> File
Plotter
No
Yes
Press ‘On’ and the following display appears: -
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> Measurement
Time to stop
Time to torque
With ‘Measurement’ selected, press ‘ENTER’ and the following display appears: -
Select parameters
SP: L1
RPM:100.0
d: 1.0000 g/cm3
Max:
60.0
Move through the fields using TAB and edit using ENTER.
The field SP shows the spindle used for the test. The chosen spindle and the chosen
speed determine the maximum and minimum values of the viscosity (see Tables 2 to 13
for more information) as well as the shear stress measurement. To change the spindle,
you must first change the spindle selection in this submenu using the ‘∆’ and ‘∇’ softkeys.
Only after changing the configuration setting the spindle can be removed and another
fitted. The instrument displays the spindles compatible with its model.
IMPORTANT: Measurement errors will occur if you use a different spindle other than the
spindle you have set in the configuration.
The field RPM (revolutions per minute) indicates the speed at which the test is performed.
There are 19 preset times (0.3, 0.5, 0.6, 1, 1.5, 2, 2.5, 3, 4, 5, 6, 10, 12, 20, 30, 50, 60, 100,
200 rpm). The speed and the spindle should be selected according to the viscosity to be
measured (see Tables 3 to 13).
Changing the speed: Select the field (RPM) using the TAB softkey and move up and
down the list of preset speeds using the ‘∆’ and ‘∇’ softkeys. After input of the desired
speed press TAB to go to another parameter.
The field ‘d’ (density) indicates the density of the liquid to be tested. The density of water
is given as the default. However, you can select any value. The unit is kg/m3 if you have
selected the SI system of units or g/cm3 if you have selected the CGS system of units. To
change the density, use the softkeys as described in previous sections.
NOTE: If you change the density from the default value, the viscometer will give the
measurements in cSt (centiStokes) and if you maintain the initial density, it will give the
measurements in cP (centiPoise) or mPa·s.
When all the values in the display are entered as desired, press ‘ON’. The measuring
display appears. Pressing QUIT returns you to the display for configuring the outlets. All
data entered in the measurement configuration display will be lost.
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6.4 Measuring display
When this display appears, the viscometer starts moving the spindle and acquiring data.
The following is an example of data shown on the display:
SP: L1 RPM:100.0
V:
2012.4 cP
63.1 %
34.3 ºC
As the instrument continues measuring the viscosity with each turn of the spindle the
data are constantly updated. The display shows:
• SP: Spindle currently in use. (Selected in the previous display).
• RPM: Revolutions per minute. (Selected in the previous display).
• V: Viscosity. Displayed in cP or mPa·s or in cSt (centiStokes) if you have entered
the density of the sample.
• %: Percentage of the full scale (i.e. percentage of the rotational twist of the spring
corresponding to the upper limit).
• ºC: Temperature of the sample. Depending on the units selected, the temperature
appears in degrees Centigrade (°C) or degrees Fahrenheit (ºF).
In addition to observing the measurements taken, the user has other options in this
display. Pressing the different softkeys has the following effect:
Pressing the ‘∆’ and ‘∇’ softkeys increases or decreases the rotational speed of the
spindle by 5 rpm. It is therefore easy to change the speed without even leaving the
measuring display.
Pressing the ‘ON’ softkey stops or starts the motor, allowing short pauses in the test.
When this softkey is pressed, the following display appears:
Motor stop
Pressing QUIT when this display is shown abandons the measurements and returns the
instrument to the main display. Pressing ‘ON’ when this display is shown ends the pause:
the measurements continue from the point they had reached before the pause began
and the measuring display is shown again.
Pressing the QUIT softkey in the measuring display, stops the measurement and returns
you to the main menu.
These are all the measuring options available to the user when working with a spindle
which does not permit shear rate and shear stress measurements (i.e. when working with
standard spindles supplied with the instrument, see Tables 2, 5 and 8). However, if you
have selected a coaxial spindle which does permit these types of measurement (see
Tables 3, 4, 6, 7 and 9, special spindles), pressing TAB switches from the main
measuring display to the secondary measuring display. For example:
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SP: TL5 RPM:100.0
SR: 132.0
SS: 212.4
45.3 % 43.3ºC
Here, the display differs from the main measuring display. Some fields are the same: SP
(spindle), RPM (speed of rotation), % (percentage of full scale) and ºC (temperature in
degrees Centigrade). There are two additional fields: SR and SS (shear rate and shear
stress).
The softkeys have the same function as in the main measuring display, i.e. the ‘∆’ and ‘∇’
softkeys to increase or decrease the speed, QUIT to abandon the measurements, ‘ON’ to
make a pause in the test (Motor stop) and TAB to switch, in this case back to the main
measuring display.
7. Memories menu
Enter this menu from the main instrument menu by selecting the option ‘Test Profiles’ and
pressing ENTER. At a basic level, a memory serves to store the complete information for
a measurement configuration (i.e. selected outlets, selected type of spindle, rotational
speed and sample density).
This function is very useful if a user wishes to repeat the same measurement over and
over again (as is often the case in quality control laboratories). The configuration is
defined once and then stored in the memory to be used whenever required. The
memories menu has two options: defining a memory and using the contents of a memory.
The Memories submenu display is as follows:
> Select Profile
Edit Profile
NOTE: Selecting the option ‘Select Profile’ assumes that a memory has previously been
written and stored. Writing and storing a memory is described in detail in a later section.
7.1 Option: using a memory
Select the option ‘Select Profile’ in the previous display and press ENTER. The following
display appears:
> File
File
File
File
0
1
2
3
A list of 10 memories numbered from 0 to 9 is shown. Select the memory (File) you wish
to use and press ENTER. If the selected memory cannot be used, (i.e. it contains no
information) a display appears to indicate this fact. If the memory can be used, a display
appears with a description of the memory contents. For example:
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Measure
SP: L1 RPM:100.0
d: 1.0000
In this case, spindle L1 is selected with a speed of 100.0 rpm and the sample density is
given as 1.0000 g/cm3. Pressing QUIT cancels the selection. Pressing ENTER selects the
memory for the measurement.
Pressing ENTER also brings you to the measuring display (see section 4.4). The user
can then use the instrument as described before.
7.2 Option: writing a memory
Select the option ‘Edit Profile’ in the display and press ENTER. The following display
appears:
> File
File
File
File
0
1
2
3
The list of 10 memories numbered from 0 to 9 appears. Select the memory (File) you
wish to write and press ENTER. This brings you to the measurement configuration
display (section 4).
Write the memory in this function and select ‘on’ to store memory.
NOTE: If you select a memory which has already been written, these values will be lost
and replaced by the new configuration.
From the moment you enter the Measurement Display, the system is exactly the same as
it is when you arrive at the display via the main menu. You can define the plotter, the file
output, the spindle as well as the rotational speed and the sample density.
Once these parameters have been set, press ‘ON’ in the submenu for selecting the
measuring parameters. This saves the measuring configuration in the memory (‘Write
Memory’)
8. Autotest menu
The Autotest is a way of checking the function of the viscometer and detecting problems.
Performing an Autotest is very simple: just choose the option ‘Autotest’ from the main
menu. The following display appears:
Remove the
spindle
and
press <ON>
When this message appears, dismount the spindle. The instrument should be without
load. Press ‘ON’. This activates the Autotest. During this process, the display is as
follows:
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