Middle East
November 22, 2022
The TDR-315N is Acclima’s flagship Soil Smart TDR moisture sensor. It has a much higher amplitude waveform than our H-series sensors, which consumes more power but makes it very effective in taking accurate measurements in challenging soil environments. Being part of the Soil Smart Series means that its advanced waveform analysis works with all mineral soil types. It is a complete integrated time domain reflectometer that combines ultra-fast waveform generating and digitizing functions with a precision 5 pico-second resolution time base and highly sophisticated waveform digitizing and analyzing firmware that provides true time domain analysis of soil-propagated waveforms. Its longer waveguides provide a very large sampling volume and high accuracy of the waveform propagation.
Its form factor is designed for shallower horizontal installations where it is pushed into the sidewall of a trench that has been dug to the desired measurement depth. A probe guide is provided to ensure that the waveguide rods are parallel when pushing them into the soil. It provides reading data through a 3-wire SDI-12 interface and is compatible with any data recorder that is compliant with SDI-12 version 1.4 and earlier.
Its form factor is designed for shallower horizontal installations where it is forced into the sidewall of a trench that has been dug to the desired measurement depth.
[1] Percent Full scale, i.e., +/- 2 percentage points.
[2] VWC is calculated based on relative permittivity using the formula derived by Topp with minor modifications toallow readings in slurries and pure water. The relative permittivity of water varies with temperature, so to see a reading near 100%, the sensor must be fully immersed in water long enough to equilibrate temperature with the water. The water should be at 20.5C with at least 4cm of water around the rods on all sides, beyond the tips of the
rods, and at least 1cm of the sensor body immersed. VWC readings higher than 100% are possible when the permittivity is higher than 80 and/or temperature compensation is active.
[3] The temperature sensing element is located next to one of the outer waveguide electrodes.
Stresses beyond those specified below may cause permanent damage to the sensor. These are stress ratings only and operation at these levels is not implied.
Copyright Acclima ©, Inc. All rights reserved.
