RS485 Combined Wind Speed & Direction Sensor Anemometer & Wind Vane

Specifications

• Operating Voltage: 12V – 24V DC
• Communication Interface: RS485 (Modbus RTU Protocol)
• Wind Speed Range: 0 to 30 m/s
• Wind Speed Accuracy: ±(0.3 + 0.03V) m/s
• Wind Direction Range: 0 to 360° (16 Directions / 8 Compass Points)
• Wind Direction Accuracy: ±1°
• Start-up Wind Speed: ≤ 0.5 m/s
• Output Cable Design: Bottom outlet with integrated mounting flange
• Baud Rate: Default 4800 / 9600 bps (configurable)
• Modbus Device Address: Default 0x01 (configurable)
• Housing Material: High-strength Polycarbonate / Aluminum Alloy blend
• Cable Length: 1 meter

Minimum hardware 

• RS485 to TTL Converter Module  required to translate the industrial RS485 differential signals into standard 5V or 3.3V UART serial logic readable by your microcontroller.
• 12V to 24V DC Power Supply  essential because the sensor's internal signal processing circuitry operates strictly on industrial voltages and will fail to power up from 5V logic lines.
• Arduino Uno, ESP32, or PLC  required to transmit Modbus RTU request frames and parse the returned wind speed and direction data bytes.

Safety Warnings

• Voltage Mismatch Warning: Never supply 12V–24V directly to your microcontroller's logic pins. Ensure the power supply strictly feeds the sensor's power wires while signal lines interface through an isolated RS485 converter module.
• Reverse Polarity Guard: Double-check wire color codes prior to applying power. Reversing VCC and GND will damage the internal Modbus transceiver board.
• Logic Level Safety: Connecting the RS485 A+ and B- lines directly to an Arduino or ESP32 GPIO pin without a MAX485/TTL adapter will permanently damage the microcontroller.

Accessories Included in the Box

• 1× KM53B88 Combined Wind Speed & Direction Sensor (3-Cup Anemometer + Wind Vane unit) with integrated bottom outlet cable (1-meter) and flange mount

Frequently Asked Questions

• Is this sensor compatible with standard 5V Arduino boards?
  Yes, but you must use an external RS485 to TTL converter module to translate the industrial differential signals into 5V logic.
• Can I connect this directly to an industrial PLC?
  Yes, the sensor outputs standard Modbus RTU over an RS485 two-wire bus, making it natively compatible with most industrial programmable logic controllers.
• Does this sensor work with 3.3V microcontrollers like the ESP32 or Raspberry Pi Pico?
  Yes, provided you use a 3.3V-compatible RS485 transceiver module (like the MAX3485) to ensure you do not overvoltage your GPIO pins.
• Can I chain multiple RS485 sensors on the same bus?
  Yes, the Modbus RTU protocol allows multiple sensors (such as soil moisture and wind sensors) to share the same two-wire bus by assigning each a unique device address.
• What voltage is required to power this combined wind sensor?
  The sensor requires a stable 12V to 24V DC power supply to operate its internal signal processing and transmission circuitry.
  
• Can I power the sensor directly from an Arduino's 5V pin?
  No, 5V is insufficient to power the sensor; it will not turn on or transmit any data without a 12V–24V source.
  
• How much current does this sensor draw during normal operation?
  The combined sensor module is highly efficient and typically draws less than 50mA when powered at 12V DC.
• What do the four wires coming out of the bottom outlet correspond to? Typically, the Red or Brown wire is VCC (12V-24V), Black is GND, Yellow or Green is RS485 A+, and Blue or White is RS485 B-.
  
• Do I need to connect the sensor's ground to my microcontroller's ground? Yes, establishing a common ground between the sensor's external power supply and your microcontroller setup is strictly required for stable RS485 communication.
  
• Does it matter which way the RS485 A and B lines are connected?
  Yes, RS485 is a polarity-sensitive differential signal; swapping the A+ and B- lines will prevent communication entirely, though it usually won't cause permanent damage.
• Why am I receiving timeout errors when requesting data in my code? Timeout errors almost always mean the RS485 A/B wires are swapped, the baud rate mismatches (check if default is 4800 or 9600), or you are polling the wrong slave address.
  
• Why is the wind direction reading stuck on a single value?
  Ensure the wind vane arrow is free to rotate physically, and verify you are querying the correct 16-bit register address for direction rather than the speed register.
  
• My sensor returns garbage data; how do I fix this?
  Garbage data indicates signal reflection or grounding issues; verify your common ground connection and consider adding a 120-ohm termination resistor if your cable run is extremely long.
  
• How can I test if the sensor is working without a microcontroller?
  Use a USB to RS485 adapter connected to a PC and run debugging software like Modbus Poll or QModMaster to read the raw registers directly.