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Sht20 sensor and plc on rs485 modbus communication
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Sht20 sensor and plc on rs485 modbus communication
SHT20 temperature and humidity sensor with delta dvp12se11t rs485 modbus.
Hello,
I’m trying to connect the SHT20 sensor with my DVP12SE11 T PLC in WPLL software with Modbus RTU RS-485 connection to read the temperature and humidity sensor values. Here, I used the sht20 sensor model is MD02, but I wrote the PLC program at that address it’s reading the random values.
Here I have attached the program.
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1 Reply
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Random values usually happen due to register address offsets or mismatched serial settings.
Try these quick fixes:
Check Register Addresses:
Temperature: 0x0001 (or 1 Decimal).
Humidity: 0x0002 (or 2 Decimal).
Delta Tip: If the data looks wrong, shift the address down by 1 to 0x0000.
Divide by 10:
The sensor sends values scaled by 10. A raw reading of 255 means 25.5°C.
Check COM Port Settings (D1120):
Default SHT20/MD02 settings are usually 9600 baud, 8 data bits, No parity, 1 stop bit (8, N, 1), Slave ID = 1. Ensure D1120 in Delta matches this.
WPLSoft Instruction:
Use the standard read instruction: MODRD K1 H1 K2 (Slave ID 1, Register 0x0001, Read 2 Registers).
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