NB-IoT Soil Moisture Sensor

General Notes:

• FDR sensors need to have good contact with the medium they measure with no air gaps. All the metal electrodes must be inserted into the soil during measurement;

• Avoid direct sunlight on the sensor, which will cause excessive temperature;

• Do not bend the metal electrodes violently, do not pull the sensor lead wire with force, and do not beat or violently impact the sensor;

• The protection grade of the sensor is IP68, which can soak the sensor in water;

• Since the electrode directly measures the conductivity of the soluble salt ions in the soil, the soil volumetric water content must be higher than about 20% when the soluble ions in the soil can accurately reflect the conductivity of the soil. In the long-term observation, the measured value after irrigation or rainfall is closer to the true level. If you are performing a quick test, you can water the soil to be tested first, and perform the measurement after the water is fully penetrated;

• The sensor should be protected from severe vibration and impact, let alone knocked with hard objects.

Soil Surface Measurement:

- Clean the soil surface by removing the debris, and vegetation...

- Insert the electrodes completely in the soil, as in the below picture;

- If you measure on a hard surface, you should drill a hole first (the hole diameter should be smaller than the probe diameter), then insert it into the soil and compact the soil before measuring;

Multi-layer Measurement

- Make a soil profile in the vertical direction, slightly deeper than the installation depth of the bottommost sensor, between 20cm and 50cm in diameter;

- Insert the probes horizontally at different layers of soil;

- After the installation is completed, the excavated soil is backfilled in order, layered, and compacted, and horizontal installation is guaranteed.