Brookfield DVE - Page 18

AMETEK Brookeld Page 18 Manual No. M15-356-B0916
e viscometer will rotate the spindle at the selected speed when the MOTOR ON/OFF key is pressed
once.
786.7 cP
12RPM 11.8% s02
Figure II-7 (MOTOR ON)
When the MOTOR ON/OFF key is pressed again, “OFF” will be displayed beside the speed.
cP
12OFF 11.8% s02
786.7
Figure II-8 (MOTOR OFF)
Note: When the motor is ON, any change to the selected speed will be eective
immediately. Also, when the motor is turned o, the display will hold the last
measured torque value and measured viscosity.
e DVE Viscometer employs an optical signal pick-up inside the instrument to detect the torque
value of the calibrated spring. is optical signal pick-up is recorded four times per revolution of
the spindle. When the spindle begins to rotate at a dened speed, four torque values are recorded
during the rst full revolution of the spindle and averaged together. e display reports the average
value for both torque (%) and viscosity (P, cP, Pa•S or mPa•s). ereaer, the next torque value
recorded by the optical signal pick-up is averaged together with the three preceding torque values
and the newly calculated torque (%) and viscosity (P, cP, Pa•S or mPa•s) values are then displayed.
is 4x revolution pick-up and display continues as long as the motor is on.
is algorithm in the instrument rmware is used for all viscosity and torque readings. Consequently,
the wait time to observe the initial displayed readings for torque and viscosity increase with lower
speeds.
It may also be necessary to allow time for the indicated reading to stabilize.
Note: At speeds of 1 RPM and lower, additional time may be required to allow for complete
deection of the torque sensor. e % (torque) and cP (viscosity) will ash until
2 revolutions are achieved and the % torque value is greater than 10%.
e time required for stabilization will depend on the speed at which the Viscometer is running
and the characteristics of the sample uid. For maximum accuracy, readings below 10% should be
avoided. Additional information on making viscosity measurements is available in Appendix B or
the Brookeld publication “
More Solutions to Sticky Problems”.
e DVE Viscometer will remember the selected speed and spindle when power is turned o. On
start-up, the viscometer will be set to the previously selected spindle and speed.
Please see Brookeld publication, “
More Solutions to Sticky Problems” (Chapter 3), for information
on how to select a speed.