Thermtest TLS-100 Transient Line Source (TLS-100) to measure thermal conductivity and thermal resistivity of soil, rocks, concrete and polymer

*Please contact us to get a price quote for Thermtest TLS-100 Transient Line Source*

Transient Line Source (TLS-100)

The TLS-100 is a portable meter used to measure thermal conductivity and thermal resistivity of a variety of samples, including soil, rocks, concrete, and polymers.

Best For Soil, Rock, Concrete, and Polymers

ASTM D5334-22a | IEEE 442-2017

*New version standard is ASTM D22a*

Standard Test

Method

-40°C to 100°C

The TLS-100 is a portable meter used to measure thermal conductivity and thermal resistivity of a variety of samples, including soil, rocks, concrete, and polymers. Tests can be performed with the push of a button and results displayed instantly. The second generation TLS-100 has many advancements, such as sensors which are auto-recognized, with corresponding testing parameters automatically loaded.

The Transient Line Source (TLS) meter follows ASTM D5334 and IEEE 442-2017. The sensor needle consists of a thin heating wire and temperature sensor sealed in a 150, 100 or 50 mm steel tube. The sensor is completely inserted into the sample to be tested. Heat is delivered to the sample using a constant current source (q) and the temperature rise is recorded over a defined period of time. The slope (a) from plot of temperature rise versus logarithm of time is used in the calculation of thermal conductivity (k). The higher the thermal conductivity of a sample, the lower the slope. For samples of low thermal conductivity, the slope will be higher.

-40°C to 100°C

Temperature
Range

Testing Sensors

Standard 100 mm Sensor

Each TLS-100 comes equipped with the standard 100 mm sensor for testing of soil, soft materials, polymers, and easy to drill materials. The needle sensor is fully inserted into an isothermal sample and a measurement is made with the push of a button. After 180 seconds, results are displayed for thermal conductivity and thermal resistivity. Saved results can also be exported to a computer, via convenient utility software and USB connection.

Soil thermal dryout curves can be prepared by measuring the thermal conductivity of a sample at different moisture contents, as the sample dries from saturation. The typical drying approach involves heating the soil at an elevated temperature. The sample is removed, weighed, and measured for thermal conductivity at different time intervals, until it is fully dried.

*BELOW ARE OPTIONAL SENSOR / PURCHASED SEPARATELY*

Standard 50 mm Sensor (OPTIONAL)

The 50 mm sensor was designed for testing hard samples, like rock and concrete. Drilling the required 4 mm diameter x 50 mm hole in rigid samples is easy with the provided masonry drill bit. When testing hard samples, a thermal contact grease is used to enhance contact between the sensor and sample.

Optional 150 mm Sensor (OPTIONAL)

The optional 150 mm sensor is used for for in-lab and in-field testing of soil and soft materials according to IEEE 442-2017. The needle is fully inserted into an isothermal sample and measurement is made with the push of a button. After 180 seconds, results are displayed for thermal conductivity and thermal resistivity.

Standard 100mm – vCp Sensor (OPTIONAL)

The TLS 100 mm – vCp Sensor was designed for testing the thermal conductivity, thermal diffusivity, and specific heat of soil, soft or easy to drill materials.