5 in 1 Weather Meter with Cable Wind Speed Wind Direction Temperature Humidity Air Pressure Multifunction Wired Weather Sensor Item Type: Wired Weather Meter Product Size: Approx. 165x70mm / 6.5x2.8in Gross Weight: 457g/16.1oz Material: ABS, Aluminum Alloy Supply Voltage: DC5V Communication Type: TTL (for Modbus RTU) Cable Length: 2 Meters Operating Environment: 0‑100%RH, ‑40℃ to +60℃ Protecting Grade: IP64 Built in Sensors: Wind Speed, Wind Direction, Temperature, Humidity, Air Pressure Widely Used: Wind Direction Measurement in Greenhouse, Environmental Protecting, Ship, Wharf, Aquaculture, Advertisement Gate, Meteorology, Ocean, Environment, Airport, Harbor, Laboratory, Industry, Agriculture and Transportation Environment. Wind Speed: 0 to 45m/s range, start wind speed ≤0.8m/s, ±(0.5+0.02V)m/s accuracy, 0.1m/s resolution, 40mW power consumption Wind Direction: 0 to 359° range, ±3° accuracy, 1° resolution, 40mW power consumption Atmospheric Temperature: -40 to 80°C range, ±0.3°C accuracy, 0.1°C resolution, 1mW power consumption Atmospheric Humidity: 0 to 100%RH range, ±5%RH accuracy, 0.1%RH resolution, 1mW power consumption Atmospheric Pressure: 300 to 1100hPa range, ±0.5 hPa (25°C) accuracy, 0.1 hPa resolution, 0.1mW power consumption Sensor Total Power Consumption: <150mW Wiring Diagram: TTL signal output, the sensor wire sequence is defined as follows: Red: power positive VCC Green: power negative GND Black: TXD Yellow: RXD Note: Make sure the wiring is correct before sending power. Communicating Protocol: All commands in the manual of weather meter are RTU protocol format commands. All have been configured at the factory, if you need to modify the protocol, refer to the relevant commands or ask for help. Baud rate 9600, 8 data bits, 1 stop bit, no check. 2 frames of data communicating interval of at least 500ms. The default address is 1, and the RTU communicating format is as follows: Number of address bytes: 1 byte Number of command bytes: 1 byte Number of register address bytes: 2 bytes Number of data bytes: N bytes Number of CRC check bytes: 2 bytes I.Register address: The weather meter can integrate five modes, namely wind speed, wind direction, air temperature, air humidity, and atmospheric pressure. Each sensor has its own register address. II.Configuration address and baud rate: The commands to write the device address are the same for the weather meter. III.CRC verification steps: 1. Preset the 16 bit register to hex FFFF, call this register the CRC register 2. Isolate the first 8 bit data with the lower bit of the CRC register, and put the result in the CRC register 3. Check the lowest bit by shifting the contents of the register one bit to the right (toward the lower bit) and filling the highest bit with a 0 4. If the lowest bit is 0: repeat step 3 (shift again) if the lowest bit is 1: the CRC register is iso orthogonal to the polynomial A001 (1010 0000 0000 0001) 5. Repeat steps 3 and 4 until it is shifted right 8 times so that the entire 8 bit data is all processed 6. Repeating steps 2 through 5 for the other 8 bit data 7. The final CRC register obtained is the CRC code (the CRC code obtained is low before high). Troubleshooting: The meter displays an incorrect value when TTL is output. The meter may not be able to acquire data correctly due to wiring problems or communicating serial port failure. Please check whether the wiring is correct and firm, whether the serial port is occupied, and whether the serial port setting is correct.