Cannon CT-500, Instruction & Operation Manual

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40 CT-500 Instruction Manual
Thermometer Immersion
Proper thermometer immersion is crucial for viscosity measurements. Even a calibrated thermometer
will read incorrectly if it is improperly immersed in the bath. “Total immersion” kinematic viscosity
thermometers should be used with the bulb and entire mercury column (if applicable) beneath the
surface of the liquid, but with the emergent stem above the surface at ambient temperatures.
Viscosity Standards
Cannon Instrument Company recommends that laboratories check their kinematic viscosity
measurements with viscosity standards. If the laboratory is using CANNON calibrated viscometers and
has developed a good measuring technique, kinematic viscosity determination using a standard will
often point to temperature errors.
Viscosity standards should not be used to establish the correct temperature of the bath, however. Bath
temperature should be checked and corrected by applying the reliable thermometric techniques
outlined above.