Brookfield DV-III Rheometer - Manual (Page 21)

Brookfield Engineering Laboratories, Inc. Page 21 Manual No. M/98-211-A0701
IV. PROGRAMMING THE DV-III+ AND ANALYSIS
The programming and data analysis functions of the DV-III+ are accessed by pressing the PROG key
on the rheometer. The display will change to present a menu with three choices: DV-III, B.E.V.I.S., and
Models. DV-III and B.E.V.I.S. are the programming alternatives. Models will present the five math
models available for data analysis.
Figure 20
IV.1 Programming Concept
The DV-III+ may be programmed to collect viscosity data without operator involvement. The
captured data may be displayed and analyzed or output to a printer. Programs may be written using
two different methodologies, DV-III and B.E.V.I.S.
The DV-III programming technique uses speed/time pairs to control the DV-III+. A program
consists of multiple lines (up to 25) instructing the rheometer to operate at a particular speed for some
period of time. As an example, we can instruct the DV-III+ to rotate the spindle at 5 RPM for 30
seconds and then change speed to 10 RPM and wait 20 seconds with the following program:
Step 1 RPM = 5 Time = 00:30
Step 2 RPM = 10 Time = 00:20
A single data point will be collected at the end of each time interval.
The B.E.V.I.S. programming technique uses a custom program language to control the DV-III+. A
program consists of a series of commands instructing the rheometer in speed control, time control,
data collection, temperature control, and output. B.E.V.I.S. offers a higher level of rheometer
control compared to the DV-III method. However, the construction of B.E.V.I.S programs is more
involved. The 2-step DV-III program previously described is duplicated using B.E.V.I.S. com-
mands below:
SSN 5
WTI 00:30
PDN
SSN
10
WTI 00:20
PDN
END
The involved programming of B.E.V.I.S. commands is a small trade for the significant increase in
control capability over the DV-III method.