Brookfield DV2T Viscometer - Manual (Page 77)

Brookfield Engineering Labs., Inc. Page 77 Manual No. M13-167-B0614
However, instrument accuracy is ±2% of the maximum viscosity range and not
the standard 1%.
Calibration Procedure for Cone/Plate Viscometers
1) Follow the above procedures for mechanically adjusting the setting of the cone spindle
to the plate.
2) Refer to Appendix A; Table A-1, and determine the correct sample volume required
for the selected spindle.
3) Select a viscosity standard fluid that will give viscosity readings between 10% and
100% of full scale range. Refer to Appendix B for viscosity ranges of cone spindles.
Consult with Brookfield or an authorized dealer to determine which fluid is appropriate.
It is best to use a viscosity standard fluid that will be close to the maximum viscosity
for a given cone spindle/speed combination.
Example:
DV2TLV Viscometer, Cone CP-42, Fluid 10
Having a viscosity of 9.7 cP at 25°C
At 60 RPM, the full scale viscosity range is 10.0 cP. Thus, the Viscometer reading
should be 97% torque and 9.7 cP viscosity ± 0.197 cP (0.1 cP for the viscometer plus
0.097 cP for the fluid). The accuracy is a combination of Viscometer and fluid tolerance
(refer to Interpretation of Calibration Test Results).
4) With the viscometer stopped, remove the sample cup and place the viscosity standard
fluid into the cup, waiting 10 minutes for temperature equilibrium.
5) Connect the sample cup to the Viscometer. Allow sufficient time for temperature to
reach equilibrium. Typically 15 minutes is the maximum time that you must wait. Less
time is required if spindle and cup are already at test temperature.
6) Measure the viscosity and record the Viscometer reading in both % torque and centipoise
(cP).
Notes:
1) The spindle must rotate at least five (5) times before a viscosity
reading is taken.
2) The use of Brookfield Viscosity Standard fluids in the range of 5 cP to
5000 cP is recommended for cone/plate instruments. Please contact
Brookfield Engineering Laboratories or an authorized dealer if your
calibration procedure requires more viscous standards.
3) Select a viscosity standard fluid that will give viscosity readings between
10% and 100% of full scale range. Refer to Appendix B for viscosity
ranges of cone spindles. Do not use a silicone viscosity standard fluid
with a viscosity value greater than 5000 cP with a Cone/Plate Viscometer.
Brookfield offers a complete range of mineral oil viscosity standards
suitable for use with Cone/Plate Viscometers as shown in Table E-2.
Consult with Brookfield or an authorized dealer to determine which fluid
is appropriate.
Interpretation of Calibration Test Results:
When verifying the calibration of the DV2T, the instrument and viscosity standard fluid
error must be combined to calculate the total allowable error.
The DV2T is accurate to (+/-) 1% of the range in use when using spindles LV #1-3, RV
#2-6, HA #2-6 and HB #2-6. When using an accessory device with the DV2T such as