What Is a Tensiometer?

Soil tensiometer is a practical method to study soil water movement from the angle of energy. He is the best instrument to reflect soil moisture and guide irrigation.

Tensiometer refers to an instrument that measures the tightness of materials such as yarns, steel wires, copper wires, cables, steel cables, films, bundling materials, aluminum foils, etc. under static or dynamic conditions. It can provide accurate and quantitative tension parameters for the production process, ensuring that the tension remains stable or reaches the required value during the production process. Tensiometer mainly refers to soil tensiometer ^[1]

Measured by tensiometer

Yarn Tensiometer : measures textile materials such as yarn,

Tensiometers are like all instruments, even if the accuracy of the instrument is high, there will be certain errors and a certain measurement range.

What are the factors that affect the accuracy of the tensiometer in the selection and use of the tensiometer? Or what is the selection criteria of the tensiometer? The main factors are as follows:

1. Tension meter range selection method: Usually the maximum tension that is actually used is 80% of the tension measurement range is the best. The reason is that the calibration of the tensiometer usually uses a 2-point calibration method. The first point is 0, and the second point is 80% of the measuring range. Therefore, in theory, the 2 most accurate points for the tensiometer measurement are 0 and the effective point.

2. The selection method of the wire diameter range of the material measured by the tensiometer: Because the tensiometer adopts a 2-point linear calibration method and the working principle of the tensiometer is to measure the synergy (the pressure on the measuring point) and convert the component force by the parallelogram rule (Material tension). In this way, if the calibrated diameter of the tensiometer is different from the actual diameter of the material, the theoretical measurement value must have an error, and the larger the difference between the measured material diameter and the effective diameter, the larger the measurement error. Therefore, when selecting the tensiometer, try to make the diameter of the measured material the same as or close to the standard diameter of the tensiometer.

1. Calibration function of tension meter ^[3]

1. Boiling water cooling: After tap water is boiled for 20 minutes, it is left to cool for later use.

2. Water injection: Open the cover of the gas collecting tube, tilt the instrument, and use

1. During the use of the instrument, the air capacity in the gas collecting pipe must be checked regularly. If the air volume exceeds half of the gas collecting pipe volume, it must be refilled with water. Do not pull out the instrument or shake the instrument when replenishing. Open the lid and fill it with airless water. If during the operation, the clay pipe is loose with the original contact soil, it should be re-drilled and reinstalled nearby.

2. In general, if the air in the instrument is basically cleaned before the burial, and the humidity of the soil is within the measurement range of the instrument, it can be continuously maintained for 10-25 days without re-adding water.

1. The clay head should not be oily, so as not to block the micropores and cause the instrument to malfunction.

2. The measuring range of the instrument is 85 Kpa. When it exceeds this limit, the instrument leaks due to the water film rupture of the clay pipe wall, which makes the instrument ineffective.

3. When opening the box, it should be opened slowly, otherwise, the pointer of the vacuum gauge slams into the 0 o'clock bar due to the sudden disappearance of the pressure difference, which may easily cause the oil wire (clock oil wire) in the vacuum meter to be damaged and the vacuum meter to malfunction.

4. When covering the lid, slowly screw it in to seep the excess water from the clay head. Do not press the rubber stopper into the instrument quickly; otherwise, a high positive pressure will be generated in the instrument, which will damage the vacuum gauge and the sensor.

5. When the temperature drops to the freezing point, the instruments buried outdoors should be withdrawn to avoid frost cracking.