How to reduce the interference of ambient humidity to the accuracy of the LoRa water immersion sensor?

The LoRa water immersion sensor is a device for detecting water immersion situations based on the LoRa wireless communication technology,

How to reduce the interference of environmental humidity to the accuracy of LoRa water immersion sensor, the following methods:

1. Sensor type selection and design improvement

1. Choose sensors with high humidity interference resistance: When buying sensors, select products that are specially designed to resist interference from high humidity environments. For example, some sensors use water-vapor-resistant packaging materials, such as special silicone or polymer materials, to wrap the probes and internal circuits to prevent water vapor from entering. This material has good air permeability, which can discharge the internal moisture while preventing the intrusion of external water vapor, thus reducing the influence of humidity on the accuracy of the sensor.

2. Optimization of the probe structure: For the probe design, a double-layer structure can be adopted. The outer layer is a protective layer made of hydrophobic material, such as a metal cover coated with hydrophobic coating. When the water vapor condenses on the surface of the protective layer, water beads will roll and not touch the detection probe of the inner layer. The inner probe uses a high-precision detection electrode or capacitive plate to accurately detect water immersion.

2. Installation location and environment control

1. Reasonable selection of installation location: try to avoid installing the sensor where the humidity is easy to accumulate. For example, do not install them in poorly ventilated corners, near water pipe connections, or humidifiers that are prone to moisture production. The sensor can be installed in a position with good air circulation, such as the central area of the machine room, near the vent, or near the window (if the external environment humidity is low). This is conducive to the diffusion of humidity and reduce the impact of excessive local humidity on the sensor.

2. Control ambient humidity: If conditions permit, humidity controls the environment where the sensor is installed. In indoor environments, a dehumidifier can be used to reduce the ambient humidity. By setting an appropriate humidity threshold, when the environmental humidity exceeds a certain value, the dehumidifier automatically opens to remove the moisture in the air, so that the environmental humidity at a relatively stable level, and reduce the possibility of water vapor condensation on the sensor probe.

3. Signal processing and compensation methods

1. Humidity compensation algorithm: the humidity compensation algorithm can be added to the data processing unit of the sensor. The algorithm can correct the water immersion detection results by simultaneously detecting the ambient humidity and water immersion signals, according to the relationship model between the humidity and water immersion signal. For example, when the environmental humidity is high, the algorithm will appropriately increase the threshold of water immersion detection to avoid mistakenly triggering the alarm due to water vapor condensation. This compensation algorithm requires extensive testing and calibration of the performance of the sensor in different humidity environments to establish an accurate compensation model.

2. Signal filtering technology: use signal filtering technology to remove the noise signal caused by humidity interference. For example, using a low-pass filter can filter out high-frequency humidity interference signals, because humidity-related interference signals such as water vapor condensation usually have higher frequency characteristics. Digital filtering technology can be implemented in the microprocessor of the sensor, improving the accuracy of water immersion signals by the digital filtering of the acquired signals.

4. eriodic maintenance and calibration

1. Clean the sensor probe: Regular cleaning of the sensor probe is an important measure to reduce humidity interference. As impurities such as dust may absorb water vapor and accelerate the condensation of water vapor on the probe surface, the probe surface should be cleaned regularly. Use a clean, dry soft cloth to gently wipe the probe to remove dust and dirt from the surface.

2. Calibration sensor: Calibrate the sensor regularly to ensure that it works accurately in different humidity environments. The calibration process can be performed in a standard humidity environment, using a professional calibration equipment to adjust the parameters of the sensor, such as the detection threshold, signal gain, etc. Through the calibration, the sensor accuracy deviation due to long time use or environmental change can be corrected.