C-THERM TCi, Operator'S Manual, Page: 38 / 138

TCi Operator Manual
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4.4 Solid Testing
Solids include any non-foam solid materials such as ceramics, metals, wood, polymers, and
glass.
The power level depends on the nature of the solid. The power level for tests on low thermal
conductivity materials such as polymers, ceramics, and wood should be 90. The power level for
tests on high thermal conductivity materials such as metals should be 125.
When testing a material that is a solid but is not a polymer, ceramic, or metal use the table in the
Material Groups and Power Levels section to estimate the appropriate test method to use. Test
the material and compare it’s thermal conductivity or effusivity to the ranges listed. If the value is
within the range, the selected test method was the correct one. If the value is lower or higher
than the range, retest the material with a test method with a lower or higher range as needed.
Note on solid materials care: Be aware of the surface condition you are testing when
testing solids. A smooth presentation to the sensor face will result in more consistent
data. Damage (e.g. pitting, cracks etc.) will be detected if placed over the testing area of
the sensor. Polymers often creep (slow deformation) at room temperature so should be
placed in a consistent and safe position to avoid damage or uneven surfaces. Reference
materials should be used in the same manner all the time and test the same location to
ensure the highest possible consistency in results.
Step 1 - Spread a small quantity of contact agent on the sensor surface.
Contact agents include water, Glycol, or Wakefield 120 thermal grease.
Use three drops of glycol contact agent when testing at temperatures below 5ºC.
Use three drops of water as the contact agent when testing at temperatures between 5 and 70ºC.
Use Wakefield 120 thermal grease as the contact agent when testing at temperatures above
70ºC, when testing for long periods of time, or when testing porous or absorbent materials. See
the Contact Agents section in this chapter for more details on application.
Test contact agents on materials before testing with them to ensure that the contact agent does
not dissolve, warp or otherwise damage the material. Omit the contact agent if it can dissolve or
absorb into the sample.
Step 2 - Place the sample on the sensor.
Handle the sample with gloves to prevent thermal contamination.
Step 3 - Carefully place a weight on the sample.
If the sample is heavier than 150 grams, the weight should not be used. The sensor chip is
fragile and can be damaged if the sample and weight are not placed carefully.
Step 4 – Perform the test.
4.5 Liquid Testing
Liquid testing requires a power level of 90. There must be at least 1 mm of liquid for testing (an
approximation only, due to varying viscosities and resultant convective effects on the test).
Step 1 – Pour 35 mL of the sample liquid into a 50 mL Pyrex beaker.