TDR-305N Digital True Soil Moisture Sensor (SDI-12) - Product Summary

User 's Manual

Completely integrated TDR soil water content sensor (a.k.a., soil moisture sensor, probe, or meter) accurately yields VWC and BEC/PWEC with a high-speed 300 pico-second rise time for a detailed wave form analysis. Designed for high EC tolerance when taking readings. A great measurement solution for soils with high salt levels.

Measurement Functions：

Volumetric Water Content: 0% to 100%

Medium Permittivity: 1 to 100

Medium Bulk Electrical Conductivity: 0 to 10000 μS/cm

Medium Temperature: -40℃ to +55℃

Pore Water EC (Hilhorst Model): 0 to 55000 μS/cm

Features：

1. SDI-12 Interface

2. 3-element 5 cm stainless steel waveguide

3. 5 m 3-conductor waterproof cable (standard)

4. Waterproof Epoxy-filled Housing

5. 20% to 80% Incident Wave Rise Time: 300 ps

6. Waveform Digitizing Resolution: 5 ps

7. Incident Wave Amplitude: 2.3 V

Main advantages：

Accurate and efficient

TDR-305N is an improved version of TDR-310N. The short waveguide allows the sensor to make very shallow measurements and can be used in higher conductivity environments at the expense of the total measurement volume. It has high voltage waveform output, which enables it to effectively measure soil conductivity when it is high, and consumes more power than TDR-315H. It is a complete integrated time domain reflectometer, which combines fast waveform generation and digitization functions with accurate 5 picosecond resolution time base and complex waveform digitization and analysis firmware to provide real time domain analysis of soil propagation waveform. Its shape design is convenient for vertical installation in prefabricated holes with a 34mm flat bottom auger.

Data compatibility

It mates with a 1” schedule 40 PVC pipe that acts as a handle in its installation to any desired depth. 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.