Cannon Instrument CMRV-4500 - Manual (Page 35)

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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
CHAPTER
6
PREPARING FOR CMRV
TESTING/CALIBRATION
The procedures in this chapter should be followed when preparing for
CMRV-4500 testing or calibration.
NOTE In the event that the protocols of your ASTM test method differ from any
of the procedures outlined in this manual, the ASTM method should take
precedence.
A/W Heat Exchanger To prepare for operation of the CMRV-4500 unit, turn on the POWER
switch on the upper rear panel of the Air/Water Heat Exchanger.
Checking thermometers The ice point of the CMRV-4500 thermometers should be checked
periodically at 76 mm immersion, which corresponds to the depth of
immersion in the CMRV-4500 aluminum block.
Small deviations in the ice point (less than 0.4°C) should be noted and
added to (or subtracted from) calibration readings at all other tempera-
tures (See section on temperature calibration). If corrections larger than
0.4°C are needed, there may be a problem with the thermometer. Exam-
ine the thermometer for a bubble of gas in the lower reservoir, a bubble
of mercury in the upper reservoir, or a break in the mercury column. For
information on joining separated mercury columns see APPENDIX C.
Cleaning cycle
Clean the rotors and all nine viscometric cells as described in the follow-
ing procedure.
CAUTION When handling the rotors, be careful not to damage the rotor tips.
Damage to the tips will cause erroneous test results and may damage
the cells.
CAUTION When operating the CMRV, make sure that the rotor and cell numbers
coincide (use the #1 rotor in cell #1, the #2 rotor in cell #2, and so on).
Failure to do so may diminish test accuracy and void the cell calibration
constants.
Cleaning procedure
1. Remove the Plexiglas ® cover from the CMRV-4500 and place it away
from the cleaning solvents.