Cannon Instrument TESC - Manual (Page 7)

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CANNON®
TESC Operator's Manual, Rev 1.0
Overview
CANNON®’s Thermoelectric Sample Conditioner (TESC) System provides controlled sample
heating and cooling for ASTM D2983. Low cost and a small footprint, compared to other
sample conditioning options, allow several complete TESC Systems to be conveniently
operated in the same bench-top area as a single competitor unit. This gives labs optimal test
versatility and redundancy to maximize productivity and reduce downtime.
Theory of operation
The TESC System uses a method equivalent to Procedure B of ASTM D2983. To reduce test
variability, the TESC System automates or removes many of the steps required to transfer the
sample between conditioning and testing processes. Automation occurs through use of a
thermoelectrically controlled sample chamber that manages the sample, without operator
intervention, throughout the conditioning and testing processes.
Using a calibrated TESC System, an operator runs a D2983 test as follows:
1. Auto-zero the Brookfield® DV2T viscometer.
2. Measure 20 mL of sample into a 25 mm × 150 mm, rimless test tube.
3. Carefully place the test tube with the sample into the TESC sample chamber.
4. Attach a #4B2 spindle to the DV2T and lower the viscometer into the run position.
5. Launch both the temperature control program and the viscometer program.
Once the temperature control program starts, the TESC System heats the sample to the
preheat temperature and maintains it at that temperature for the required time. The TESC
System then cools the sample to room temperature at the same rate used to raise it to the
preheat temperature, and then further cools the sample to the desired test temperature
according to the equation in D2983 Annex A1. This controlled heating and cooling is critical to
reducing variability.
Throughout the thermal conditioning process, the DV2T program records the temperature of
the sample chamber while waiting to measure the viscosity. When thermal conditioning of
the sample completes, the DV2T automatically measures the sample viscosity by stepping