Cannon Instrument CMRV-4500 User Manual

Page 72

CANNON

Mini-Rotary Viscometer CMRV-4500 Instruction & Operation Manual

Version 1.1e—October, 2011 •

CANNON

Instrument Company

2139 High Tech Road • State College, PA • 16803 • USA

ASTM D 3829 and 4684 specify an initial weight of 10-grams, and increase
of weight in 10-gram increments. ASTM D 6821 specifies an initial weight
of 2.5 grams and increase of weight in 2.5-gram increments.

6. Ensure that a Sample ID has been entered for each sample. Then

click

for the desired sample. OR use the

Tab

key to highlight

the yield stress icon and then press

R. The

Yield

LED (light-

emitting diode) on the CMRV-4500 will glow and the

Start Test

button will begin flashing rapidly.

7. Press the flashing

Start Test

button on the CMRV front panel and

proceed immediately to step 8.

8. Slide the rotor locking pin

upward to its detent position,
allowing the weight/hook-
cage to hang free. The Yield
LED will flash as the CMRV
microprocessor measures the
wheel rotation (See Notes on
yield testing on the next page
regarding the ASTM D 4684
method). If no yield stress is
observed (sufficient rotation),
the blinking Yield Stress light
on the instrument front panel
will turn off. If it does,
conclude the test by lowering
the locking pin to prevent the
rotor from further rotation.

9. (Optional) If there is insufficient movement of the rotor during the

15-second sampling period, follow the screen prompts to add weight
to the hook-cage per ASTM methodology (see photo). The CMRV-
4500 will calculate the range for the yield stress value. If there has
not been adequate movement of the rotor by the time the weight load
reaches 100 grams, the MRVW software will calculate a minimum
value in Pascals for yield stress.

NOTES

When adding weights to the hook-cage, support the hook cage with one
hand while keeping some tension on the thread. When releasing the
hook cage use a smooth downward motion of the hand to prevent the
hook-cage from swinging back and forth and to avoid jarring the rotor.

To view test results as soon as they have been recorded in the data-
base, open an MRV Data Table analysis with the Use Dynamic Update
option (see Chapter 13).

CAUTION

Make sure to wait for the CMRV software prompts before adding addi-
tional weights.

Adding a 10-gram weight to the
hook-cage during yield stress test