Brookfield DV2+Pro Viscometer - Manual (Page 22)

Brookfield Engineering Labs., Inc. Page 22 Manual No. M03-165-F0612
The DV-II+Pro may be set to stand alone mode by turning it OFF and ON again and selecting “Stand
Alone” or by removing the DVP-80 cable prior to turning the DV-II+Pro on.
Note: The DV-II+Pro cannot communicate with DVLOADER software in
the external control mode. Choose “Stand Alone” when presented
with Figure II-23 if you want to use DVLOADER.
For information on controlling the DV-II+Pro from Rheocalc software, check the HELP menu
within Rheocalc.
II.10 Making Viscosity Measurements
The following general procedure is used for making viscosity measurements. Brookfield recommends
the use of a 600 ml Low Form Griffin beaker (Brookfield Part No. BKR-600ml) when using LV/
RV/HA/HB spindles.
1. Mount the guardleg on the DV-II+Pro Viscometer (LV and RV series) and insert into the container.
2. Insert and center spindle in the test material until the fluid’s level is at the immersion groove
on the spindle’s shaft. With a disc-type spindle, it is necessary to tilt the spindle slightly while
immersing to avoid trapping air bubbles on its surface.
A) If you have a standard viscometer, attach the spindle to the coupling nut on the
lower shaft of the viscometer. Lift the shaft slightly, holding it firmly with one
hand while screwing the spindle on with the other (note: left-hand thread). Avoid
putting side thrust on the shaft. Verify the proper spindle immersion depth and that
the viscometer is level.
B) If you have an EZ-Lock viscometer, with one hand hold the spindle, while gently
raising the spring-loaded outer sleeve to its highest position with the other hand, as
shown in Figure II-7. Insert the EZ-Lock Spindle Coupling so that the bottom of
the coupling is flush with the bottom of the shaft, and lower the sleeve. The sleeve
should easily slide back down to hold the spindle/coupling assembly in place for use.
3. The process of selecting a spindle and speed for an unknown fluid is normally trial and error. An
appropriate selection will result in measurements made between 10-100 on the instrument
% torque scale. Two general rules will help in the trial and error process.
1) Viscosity range is inversely proportional to the size of the spindle.
2) Viscosity range is inversely proportional to the rotational speed.
To measure high viscosity, choose a small spindle and/or a slow speed. If the chosen spindle/
speed results in a reading above 100%, then reduce the speed or choose a smaller spindle.
Experimentation may reveal that several spindle/speed combinations will produce satisfactory
results between 10-100%. When this circumstance occurs, any of the spindles may be selected.
Non-Newtonian fluid behavior can result in the measured viscosity changing if the spindle and/
or speed is changed. See our publication, “More Solutions to Sticky Problems,” for more detail.
Turn on motor.
Allow time for the indicated reading to stabilize. The time required for stabilization will depend
on the speed at which the Viscometer is running and the characteristics of the sample fluid. For