Industrial RS485 MODBUS Temperature & Humidity Sensor

Overview

An Industrial RS485 MODBUS Temperature & Humidity Sensor is a rugged digital environmental sensing device used in industrial automation systems.

• Measures:

  • Temperature

  • Relative Humidity

   

• Outputs data via:

  • RS485 communication

  • MODBUS RTU protocol

   

Designed for PLC, SCADA, and industrial IoT systems

Working Principle

• Uses:

  • Capacitive humidity sensor (polymer-based)

  • Bandgap / thermistor temperature sensor

   

• Internal system:

  • Signal conditioning

  • ADC conversion

  • Digital processing

   

• Data is transmitted via:

  • RS485 differential communication

  • MODBUS RTU registers

   

glues using Modbus function codes (e.g., 0x03)

Measurement Characteristics

Temperature

• Typical Range: 40C to +125C

• Accuracy:

  • 0.1C to 0.5C (high-precision models)

   

Humidity

• Range: 0% to 100% RH

• Accuracy:

  • 1% to 3% RH

   

Resolution

• Typically:

  • 0.1C

  • 0.1% RH

   

Electrical Characteristics

• Supply Voltage:

  • 5V 30V DC (common)

  • Industrial range: 9V 36V DC

   

• Power Consumption:

  • Low (typically <10 mA)

   

Communication Interface

RS485 Interface

• Differential signal (A+l

  MODBUS RTU Protocol

  • Industrial standard protocol

  • Features:

    • Device addressing (1247 or more)

    • Configurable baud rate (9600115200)

    • Register-based data reading

     

   

  Fully compatible with:

  • PLC

  • SCADA

  • Industrial controllers

   

  Physical & Mechanical Design

  Housing

  • Industrial-grade materials:

    • ABS plastic

    • Aluminum alloy

     

  • Features:

    • Dust-proof

    • Waterproof (IP-rated in many models)

    • Corrosion-resistant

     

   

  Probe Design (common type)

  • Stainless steel probe

  • Breathable membrane

  • Cable length: ~12 meters

   

  Internal Features

  • Factory calibration

  • Digital filtering and compensation

  • Temperature compensation for humidity

  • Configurable paramet Functional Behavior

    • Continuously measures environmental data

    • Sends values via MODBUS registers

    • Typical reading:

      • Temperature = register value 10

      • Humidity = register value 10

       

     

    Key Technical Features

    • Industrial-grade reliability

    • Long-distance communication (RS485)

    • Standard MODBUS RTU protocol

    • High accuracy and stability

    • Wide operating range

    • Easy integration with automation systems

    • Configurable communication parameters

     

    Applications

    • HVAC systems

    • Industrial automation

    • Greenhouses & agriculture

    • Cold storage monitoring

    • Data centers

    • Smart buildings

    • Weather stations

    • Environmental monitoring systems

     

    Advantages

    • Robust communication over long distances

    • Noise immunity (RS485 differential signaling)

    • Easy integration with industrial systems

    • High accuracy and stability

    • Suitable for harsh environments

     

    Limitations

    • Requires:

      • RS485 interface / converter (for MCU use)

       

    • MODBUS protocol handling needed

    • Slightly higher cost than basic sensors

    • Slower compared to direct analog sensors (due to protocol overhead)

     

    Technical Summary

    An Industrial RS485 MODBUS Temperature & Humidity Sensor is a professional environmental sensing solution that:

    • Combines high-accuracy sensing + industrial communication

    • Enables long-distance, reliable data transmission

    • Is optimized for PLC, SCADA, and industrial IoT systems

     

    It is best classified as a temperature-humidity transmitter (industrial-grade) rather than a s