How does the Evaporation Sensor work?

Evaporation sensors, usually using the weighing principle or pressure principle, measure the change in weight of the liquid in the evaporating dish and then calculate the change in liquid level to monitor evaporation. This type of sensor can be adapted to the measurement of evaporation on the surface of the water under various environmental conditions, especially in the environment where the liquid may freeze, and overcomes the disadvantages of the use of ultrasonic principle of measuring the height of the liquid surface, such as the inaccuracy of the measurement of the icing, the sensor is easy to be damaged when there is no water, and the low accuracy of the measurement. The following are the operating principles and characteristics of evaporation sensors:

 Evaporation sensor working principle

1. weighing principle: the evaporation sensor is equipped with a high-precision load cell inside, which is used to measure the weight of the liquid in the evaporation dish. As the evaporation process proceeds, the weight of the liquid gradually decreases and the load cell captures this change.

2. pressure principle:

2.1. Pressure change detection: the sensor is equipped with a high-precision pressure sensor inside the sensor, which is used to measure the pressure of the liquid at the bottom of the evaporation dish against the bottom surface of the container. As the evaporation process proceeds, the weight of the liquid gradually decreases, resulting in a lower pressure acting on the bottom of the vessel.

2.2. Liquid level height calculation: Through the measured pressure change, combined with the size of the evaporation dish and the density of the liquid, the change in liquid level height can be calculated. Since the dimensions of the evaporating dish are fixed, the evaporation can be deduced from the mathematical relationship between the pressure change and the liquid surface height.

2.3. Data Output and Conversion: The sensor converts the detected pressure changes into electrical signals, such as 4-20mA current signals or digital signals (e.g. Modbus-RTU protocol), for easy remote monitoring and data logging. These electrical signals are proportional to the pressure change and thus to the evaporation.

Evaporation sensor features and advantages

Highly adaptable: Evaporation sensors, especially models based on the pressure measurement principle, are excellently adapted to a wide range of environmental conditions, including extreme low temperatures leading to icing, ensuring that evaporation can be accurately measured in a variety of complex environments.

High accuracy: The use of high-precision pressure sensors or weighing technology captures small pressure or weight changes to provide precise evaporation measurement data and improve measurement accuracy.

High reliability: The sensor design takes into account the working stability under extreme conditions, such as liquid freezing and waterless condition, etc., to ensure that the sensor will not be damaged under these conditions and maintain long-term stable operation.

Dustproof, waterproof, anti-corrosion: special design makes the sensor has excellent dustproof, waterproof and anti-corrosion ability, effectively reduce the impact of environmental factors on the measurement accuracy, and reduce maintenance costs.

Strong anti-interference ability: the sensor has anti-electromagnetic interference and other characteristics, to ensure that in the harsh electromagnetic environment can still provide accurate measurement data.

Easy to integrate and maintain: the electrical signal output from the sensor is easy to integrate with automatic weather stations, data acquisition systems, etc. to achieve remote monitoring and automated management. At the same time, the optimisation of the design reduces maintenance requirements and improves overall operational efficiency.

Automated monitoring and data storage: Used in conjunction with automatic water refilling devices, data collection and sending devices, etc., the evaporation sensor can realise automatic monitoring of the evaporation process and real-time storage of data, improve data collection efficiency and accuracy, and ensure the continuity and integrity of the data.

Remote transmission and integrated applications: the sensor can be integrated with other meteorological observation equipment (such as rainfall sensors) and data collection and transmission devices to achieve automatic observation and remote transmission of evaporation, rainfall and other meteorological processes. This integrated application makes it possible to carry out long-term monitoring in remote or hard-to-reach areas, providing important data support for weather forecasting and water resource management.

 Evapotranspiration Sensor Application Scenarios:

Evapotranspiration sensors are widely used in meteorological observation, agricultural irrigation management, water resources research, environmental monitoring and other fields, especially in the need for long-term, continuous monitoring of evapotranspiration occasions, such as lakes, reservoirs, farmland, forests, and other natural and artificial bodies of water evapotranspiration monitoring plays an important role.

1. Meteorological observation: In meteorology, water surface evaporation is one of the important factors affecting climate and weather patterns. Through the use of water surface evaporation sensors, meteorologists can collect data on evaporation rates, which is essential for predicting weather changes, understanding water cycle processes, and assessing drought risk.

2. Plant Cultivation and Seed Cultivation: In agriculture, understanding soil moisture evaporation is critical to optimising irrigation schedules and improving crop yields. Surface evaporation sensors can help farmers and researchers monitor soil moisture loss to develop more effective irrigation strategies.

3. Agroforestry: In forestry and crop management, evapotranspiration monitoring can help assess water needs and irrigation efficiency. By monitoring evapotranspiration, water resources can be better managed and wastage can be reduced, while ensuring that plants receive sufficient water.

4. Geological surveys: In geological studies, water surface evaporation sensors can be used to monitor changes in groundwater levels, which is important for studying groundwater recharge and depletion, and assessing the health of groundwater systems.

5. Scientific research: In fields such as ecology, hydrology and environmental sciences, water surface evaporation sensors are a key tool in the study of the water cycle, ecosystem balance and the effects of climate change. They help scientists collect data to understand how natural systems respond to environmental change.

6. Environmental monitoring: In environmental protection and water resource management, monitoring water surface evaporation helps assess the health of water bodies, predict the sustainability of water resources, and develop effective water resource management policies.

In short, the evaporation sensor uses high-precision weighing or pressure sensing technology to accurately measure the weight or pressure change of the liquid in the evaporation dish to calculate the amount of evaporation. The sensor has excellent environmental adaptability, high measurement accuracy and long-term operational reliability, as well as dust-proof, water-proof and corrosion-proof features that reduce maintenance requirements. It plays an important role in meteorological observation, agricultural irrigation, water resources research, etc. It provides accurate data support for weather prediction, crop irrigation management, water resources assessment, etc. It is an important tool for modern water resources management and environmental monitoring.