Taidacent SHT30 RS485 Modbus RTU Temperature and Humidity Sensor Transmitter for PLC and DCS Room Thermocouple Monitoring

Excellent for price. n = no parity. My PLC only allows 400001 as starting address, where the instructions said 40001. However, when I entered 400001 it did not matter, it gave me the results. Don't forget to divide the numbers by 100 to get the correct temperature and % humidity. Convert from Deg C to Deg F by multiplying by 1.8 and adding 32. I also forgot to hook up the red wire. It works fine with 24 VDC.

Works fine, you just have to poll function code 03 (holding registers) and the transducer I received had slave address 01. Temperature is located at register 1 (address 0) and humidity is register 2 (address 1). IMPORTANT I found that if you poll more than 2 registers in one message, the transducer seems to go into an 'auto broadcast' mode, where it automatically transmitts on a 1-2 second interval. This gave me a bit of a headache.

It connected right up to my USB-to-RS485 interface, and my PC could read it right away using python's pymodbus module. Value agrees with other temperature sensors.

Exactly what I needed, I had it working in minutes.

Got this working by powering red wire with 24vdc, green ground. Baud rate 9600, 8 data bits, parity none, 1 stop bit, slave node # 1.