Air Temperature and Humidity Sensor Overview The Air Temperature and Humidity Sensor is a high-precision environmental monitoring device designed for industrial, agricultural, and smart-city applications. Equipped with a high-sensitivity probe, it delivers stable, accurate, and reliable measurements of both temperature and humidity in real time. With a wide measurement range, excellent linearity, and strong waterproof performance, this sensor ensures consistent operation even in challenging environments. It supports RS485 Modbus-RTU communication, allowing easy integration with control systems, IoT platforms, and data loggers. Its compact design, long transmission distance, and easy installation make it ideal for large-scale deployment. Key Features of Air Temperature and Humidity Sensor High Precision: ±0.3°C temperature accuracy and ±2–4%RH humidity accuracy depending on probe type (SHT20–SHT75). Fast Response: Delivers readings within 15 seconds for rapid monitoring. Wide Range: Measures temperature from –40°C to 80°C and humidity from 0–100%RH. RS485 Output: Ensures stable digital communication over long distances. Durable Design: Dustproof, waterproof, and built to withstand harsh environments. Low Power Consumption: Operates efficiently with a 12–24V DC power supply. Easy Installation: Supports wall, rail, or panel mounting with simple wiring. Technical Specifications Parameter Specification Power Supply 12–24V DC Output Signal RS485 (Modbus RTU) Power Consumption ≤0.15W @ 12V DC Temperature Range –40°C to 80°C Humidity Range 0–100% RH Temperature Resolution 0.1°C Humidity Resolution 0.1% RH Response Time ≤15 seconds Stability (Temp/Humidity) ≤0.1°C per year / ≤1% RH per year Probe Options and Accuracy The sensor supports multiple probe configurations depending on accuracy requirements: Model Probe Type Temperature Accuracy Humidity Accuracy –S20 SHT20 ±0.3°C ±3–7% RH –S30 SHT30 ±0.3°C ±2–4.5% RH –S31 SHT31 ±0.3°C ±2% RH –S75 SHT75 ±0.3°C ±1.5–3% RH Hardware Design and Installation The Air Temperature and Humidity Sensor is available in several housing options — economical rail-mount, LCD display shell, and wall-mounted enclosure — to suit different environments. The device uses industrial-grade connectors for reliable communication and long-term stability. When wiring the RS485 interface, ensure the A/B lines are correctly connected and device addresses are unique on the bus to avoid signal conflicts. The 12–24V wide voltage input provides flexible installation across different setups. Wiring Overview VCC: Power positive (12–24V DC) GND: Power negative 485-A / 485-B: Communication lines Note: Incorrect wiring may cause permanent device damage. Verify line sequences before powering up. Integration and Communication The sensor uses the Modbus RTU protocol, making it compatible with most industrial PLCs, SCADA systems, and IoT gateways. Supported baud rates include 2400, 4800, and 9600 bps, with the default set at 9600. Each sensor can transmit data for: Register 0000H (Humidity) — unit: 0.1% RH Register 0001H (Temperature) — unit: 0.1°C You can easily integrate the device into building automation systems or industrial process controls for real-time monitoring, data logging, and trend analysis. Software Configuration and Calibration NexaSens provides a Configuration Tool that allows users to connect the sensor to a PC using a USB-to-RS485 adapter. Through this software, you can: Modify communication parameters (baud rate, address). Test real-time data readings. Perform sensor calibration. Routine calibration ensures that the sensor maintains optimal accuracy over long-term use. Applications The Air Temperature and Humidity Sensor is suitable for a wide range of environments, including: Industrial automation and process control Greenhouses and precision agriculture Smart city environmental monitoring HVAC systems and building management Cold storage and data centers Reliability and Maintenance Built with industrial-grade materials, the sensor is engineered for durability and low maintenance. Its ABS enclosure resists dust and moisture, ensuring reliable operation under extreme temperature and humidity variations. Minimal maintenance and long-term calibration stability make it a cost-effective solution for continuous environmental monitoring. INTERAL LINKE  Soil 7in1 sensor ESP32 WiFi & Bluetooth Module Gas sensor for TVOC Leaf temperature and humidity sensor Photosynthetically Active Radiation Sensor solar radiation sensor External Reference Learn more about Modbus RTU communication at www.modbus.org.