How Does A Humidity Sensor Work?

Humidity sensors are a great help in households which are situated in weather diversifying areas. It helps in monitoring the humidity levels and keeps track of weather changes. You might argue the necessity of it. But these sensors have been proven helpful and efficient to control the room temperature and prevent mold formation. Helping to keep a healthy and comfortable environment in the house is the principal task of the equipment. Now the question is, what is a humidity sensor and how does it work?

What is Humidity Sensor?

An electronic device that collects data from a specific range of areas by measuring the humidity in the air, then converts the data into corresponding electrical signals and provides quantitative information to the user is called the humidity sensor. It is also called a hygrometer. It determines the amount of water present in the air. The device can be handheld or installed in the house. There are basically two types of sensors, Absolute Humidity (AH) sensor and Relative Humidity (RH) sensor. From small homes to big plants, there are all sizes of compatible sensors.

How Does a Humidity Sensor Work?

Before understanding how the device works, it is essential to know that AH sensors and RH sensors are classified into three categories. They are Capacitive, Resistive, and Thermal Conductivity. These sensors are often distinguished by some parameters, the working accuracy, reliability, response time, repeatability and linearity. Thus, let us dig into how these devices: actually work.

Capacitive Humidity Sensor: This type of sensor uses metal oxide and electrodes to measure the moisture level. The metal oxide is highly reactive to the humidity level fluctuation as its electrical capacity tends to change with it.  So the construction of a thin strip of metal-oxide between two electrodes easily detects even the slightest change in the atmosphere. Even though the equipment design has always been a matter of debate among developers, as it requires perplexing circuits and continuous calibration, A capacitive sensor can measure relative humidity (RH) from 0% up to 100%. These are linear sensors. So, the applicability is extended to very high temperatures. So it is suitable for both household and industrial usage.

Resistive Humidity Sensor: The relationship between resistance and humidity is inverse exponential. The sensor uses this inverse exponential to measure humidity.  It wields ions in salts and calculates the water particles in the environment and shows the electrical impedance of atoms. Then, it converts the data into electronics measurement. So, as the humidity levels diversify, the sensor detects the electrodes’ resistance around the salt channel. Thus, the humidity levels are determined.

Thermal Humidity Sensor: These sensors use two thermistor devices installed in one. The first thermistor is covered with dry Nitrogen tightly sealed. The other one is disclosed to the environment through small venting holes. The negative temperature coefficient between the thermistors creates resistance when the device is powered on. The difference in the two new measured values indicated the actual humidity level of the area. For its accuracy of the result, it is also called the Absolute Humidity Sensor (AH).

The Benefit of Using Humidity Sensor Switch:

Humidity sensor switches are convenient and it makes things easier for you. It comes with an easy installation process, digital and very sensitive microprocessors technology. With just a press, it detects the moisture level in the air. This switch system is very effective in bathrooms. Humidity sensor switch for bathroom fans detects the water vapor levels instantly. You can then use the ventilation fans to reduce the level to optimum. So, you should definitely look at some best switches while you are at it.

Bottom line:

In fine, we can say that these sensors come in three types of mechanism, capacitive, thermal and resistive sensors. Capacitive sensors are suitable for industrial use and large area coverage. The thermal sensor gives you more accurate results. Humidity sensor switches are more beneficial in the execution process in your home. So, now you know which one Is right for you.