The use of modern temperature and humidity sensor technology in spray painting shops can improve production quality

The two primary factors in the air—humidity and temperature—are of great significance and have a significant impact on people’s daily lives, work, and industrial production. In the coating industry, temperature and humidity in the workshop environment are strictly controlled, and mist humidifiers—as simple devices for regulating temperature and humidity—are widely used in this sector. For coating workshops, such as spray booths, strict control of temperature and humidity is required due to process needs. The built-in temperature and humidity sensors in the humidifier effectively monitor these conditions along the coating production line, thereby ensuring product quality and improving production efficiency.

In spray booths—such as those used for painting solid wood furniture—the environmental factors that most significantly affect the spray painting results are temperature, humidity, and air cleanliness. Temperature is generally maintained at 25±3°C, and humidity at 65±15%; both temperature and humidity levels that are too high or too low are undesirable. If the temperature is too high, the paint finish will have poor gloss, appear uneven and rough, develop an orange peel effect, and the paint film will appear lighter and whiter in color. As a simple humidification device, the dry mist humidifier has no complex mechanical components and provides direct, rapid humidification.

First, let’s understand the principle behind the humidifier. Simply put: due to airflow, air with higher humidity moves toward areas with lower humidity, ultimately raising the humidity throughout the space and thereby reducing the number of airborne particles. During operation, the dry mist humidification system emits water mist with an average particle diameter of 8 μm. This dense, fine mist readily captures fine dust particles in the air; the captured particles, having increased in mass, naturally fall and settle. Even uncaptured dust particles absorb moisture from the air, increasing their mass and causing them to settle naturally.

As air humidity increases, the electrostatic voltage between airborne dust particles decreases. When the relative humidity inside the production line reaches 60%, the electrostatic voltage drops to a minimum. At this point, large dust clusters formed by electrostatic forces break apart effectively, resulting in fine dust particles that will not cause paint surface defects.

A temperature and humidity sensor is a device or apparatus capable of converting temperature and humidity readings into electrical signals that are easy to measure and process. In actual production, monitoring and controlling temperature and humidity are crucial for improving production efficiency. Consequently, combined temperature and humidity sensors have emerged on the market; these sensors generally measure both temperature and relative humidity.

In common humidifier systems, a humidity sensor and an activation control valve are built in. The humidity sensor monitors the humidity inside the unit and sends feedback to the controller; the controller then regulates the valve’s opening based on the humidity level, ultimately activating the humidifier to begin humidifying the room.

Currently, most popular temperature and humidity sensors on the market feature digital output. GCAI.com has introduced a digital temperature and humidity sensor from overseas—the HTU21D. Its built-in temperature sensor is housed within the same package as the humidity sensor, enabling temperature-compensated measurement of relative humidity while providing a second independent temperature sensor output, allowing users to replace two sensors with a single unit. Furthermore, these types of temperature and humidity sensors offer the advantages of low power consumption and high accuracy. However, different temperature and humidity sensors vary greatly in principle and structure; when selecting a product, users should choose the appropriate sensor based on specific measurement objectives, the object being measured, and the measurement environment.