Brookfield DV-I Prime User Manual

Page 61

Brookfield Engineering Laboratories, Inc.

Page 61

Manual No. M/07-022-D0613

Interpretation of Calibration Test Results:

When verifying the calibration of the DV-I PRIME, the instrument and viscosity standard fluid

error must be combined to calculate the total allowable error.

The DV-I PRIME

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 RVDV-I PRIME with

RV-3 Spindle at 2 RPM; Brookfield Standard Fluid 12,500 with a viscosity

of 12,257 cP at 25°C:

1) Determine Full Scale Viscosity Range using the AUTORANGE key on your instrument

or calculate with equation:

Full Scale Viscosity Range [cP] = TK * SMC * 10,000

RPM

Where:

TK = 1.0 from Table D-2 (In Appendix D)

SMC = 10 from Table D-1 (In Appendix D)

Full Scale Viscosity Range

1 * 10 * 10,000

= 50,000 cP

The viscosity is accurate to (+/-) 500 cP (which is 1% of 50,000)

2) The viscosity standard fluid is 12,257 cP. Its accuracy is (+/-) 1% of 12,257 or

(+/-) 122.57 cP.

3) Total allowable error is (122.57 + 500) cP = (+/-) 622.57 cP.

4) Therefore, any viscosity reading between 11,634.4 and 12,879.6 cP indicates that the

viscometer is operating correctly. Any reading outside these limits may indicate a viscometer

problem. Contact the Brookfield technical sales department or your local Brookfield dealer/

distributor with test results to determine the nature of the problem.

Calculate the acceptable range of viscosity using RVDV-I PRIME with

Small Sample adapter at 10 RPM; Brookfield Standard Fluid 12,500 with

a viscosity of 12,257 cP at 25°C:

1) Determine Full Scale Viscosity Range by pressing the AUTORANGE key on your

instrument. Display shows 25,000 cP. The viscosity is accurate to +/- 500 cP (which is

2% of 25,000 cP).

2) The viscosity standard fluid is 12,257 cP. Its accuracy is (+/-)1% of 12,257 or