Brookfield DV1 Viscometer - Manual (Page 52)

Brookfield Engineering Laboratories, Inc. Page 52 Manual No. M14-023
5) Measure viscosity and record the viscometer reading; include % and cP (mPa•s). Instrument
accuracy is ± 2% of the maximum viscosity range and not the standard 1%.
Calibration Check Procedure for Cone/Plate Viscometers
1) Follow the procedures outlined in Appendix A for mechanically adjusting the setting of
the cone to the plate.
2) Refer to Appendix A, Table A-1, and determine the correct sample volume required for
the spindle to be utilized.
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. See Table F-2 in Appendix F. It is best to
use a viscosity standard fluid that will be close to the maximum viscosity for a given cone
spindle/speed combination.
DV1MLV 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 (closer to ±0.2) cP. The accuracy is a combination
of Viscometer and fluid tolerance (refer to Interpretation of Calibration Test Results at
the end of this section).
4) With the viscometer stopped, remove the sample cup and place the viscosity standard
fluid into the cup.
5) Connect the sample cup to the Viscometer. Allow sufficient time for temperature to reach
equilibrium.
6) Measure the viscosity and record the Viscometer reading in both % torque and centipoise.
NOTE: The spindle must rotate at least five (5) times before readings are taken.
Interpretation of Calibration Test Results:
When verifying the calibration of the DV1, the instrument and viscosity standard fluid error must
be combined to calculate the total allowable error.
The DV1 is accurate to (+/-) 1% of any Full Scale spindle/speed viscosity range.
Brookfield Viscosity Standards Fluids are accurate to (+/-) 1% of their stated value.
Calculate the acceptable range of viscosity using DV1MRV with RV-3
Spindle at 2 RPM; Brookfield Standard Fluid 12,500 with a viscosity of
12,257 cP at 25°C:
Example 1: