Brookfield YR-1 Rheometer - Manual (Page 36)

Brookfield Engineering Labs., Inc. Page 36 Manual No. M02-215-B0412
III.6 Test Results
III.6.1 Test Passed
When a yield test runs successfully, the resultant Yield Stress (Pa), the % Torque value at the
time of the yield and the Temperature at yield are printed.
Test (#5: Sample Tst) Complete
Yield Stress (Pa) = 726.36 % Torque @ Yield = 73.56 Temperature = 25.5C
In addition, the results are shown on the display as follows:
%=73.56 025.5C
YIELD-726.36 Pa
Figure III-21
III.6.2 Test Failed
Some of the reasons a yield test may fail are as follows.
III.6.2.1 Under-Range Condition
Only yield measurements in the % Torque range from 10% to 100% will be accepted. If
a Yield Stress is reached before the % Torque value is 10%, an Under-Range error causes
the test to end.
The following is sent to an attached printer:
Test (#5: Sample Tst) Complete
Test Failed = Under-range
The following screen is displayed:
YIELD ERROR
UNDER-RANGE
Figure III-22
III.6.2.2 Under-Range Error
The yield stress (Torque Reduction Value) is reached before the absolute % torque reaches
10%. When a test is started, once the absolute torque is greater than zero (0), the second,
third, and fourth Delta Torques (also known as the Base Increment Torque) are averaged.
The first three (3) Delta Torques after 9% absolute torque is reached are also averaged. An
under-range error occurs if the second average falls below the first average by 15% or more.