Brookfield DV2T Viscometer - Manual (Page 37)

Brookfield Engineering Labs., Inc. Page 37 Manual No. M13-167-B0614
Materials that exhibit thixotropy will show a steadily decreasing measured viscosity over
time. Materials that exhibit pseudoplasticity will show a changing viscosity as the spindle
speed changes.
TIP: When averaging data for a thixotropic material, begin the Averaging Duration after
the period of most significant change in measured viscosity. This will reduce the
variability in the averaged value.
TIP: When averaging data for a pseudoplastic material, do not average together (Test
Averaging) data collected at different speeds (or shear rates).
Live Averaging of data occurs during actual testing of a sample. Data can be collected
as an average of readings over a specific time interval; each data point saved in the file is
an averaged value. This averaging is defined in the Data Collection section of Configure
Viscosity Test.
Single Point Averaging
requires a definition of Averaging Duration, the amount of time
for which readings will be averaged. This time parameter will be applied at the end of
the End Condition. In this case a single data point will be collected which represents
the average of all data measured during the specified time period (Averaging Duration).
Multi Point Averaging
requires a definition of 1) Data Interval, the frequency of data
collection and 2) Averaging Duration, the amount of time for which readings will be
averaged. These two parameters will work in conjunction to generate multiple data
points each of which represent the average of all data measured during the average
duration within the specified Data Interval.
Post Test Averaging of data occurs after the test is complete, through the Results screen.
Averages and standard deviation values can be generated for data collected in a single
step or across several steps of a test generated through PG Flash software. If the test
used to collect data utilized Live Averaging (described above), then the Post Test Averaging
will produce an average value of averaged data points.
Post Test Averaging can be specified in the Report section of Configure Viscosity Test (see
Section III.7). When configured as part of the test, the average values will be displayed
immediately upon test conclusion. If not specified in Report, Post Test Averaging can
be selected from the Down Arrow in the Results screen (see Section III.9).
Post Test Averaging offers two options: Step Averaging and Test Averaging (see Figure
III-13).
Figure III-13