10‑30V Wall Mounted Multi Element Transmitter 485 Mode Temperature Humidity CO2 PM2.5 PM10 Sensor Item Type: Temperature and Humidity Transmitter  Material: Plastic Weight: Approx. 194g/6.84oz Size: 110x70x38mm/4.33x2.76x1.50in Coding: 8 bit binary Data Bits: 8 bits Parity Bit: None Stop Bit: 1 Error Checking: CRC (Redundant Cyclic Code) Baud Rate: 400bit/s, 4800bit/s, 9600 bit/s can be set, the factory default is 9600bit/s DC Power Supply (Default): 10 to 30V DC Power Consumption: ≤1.2W（12V DC, 25℃） Average Current: ＜85mA Transmitter Circuit Working Temperature And Humidity: -40℃ to +60℃, 0%RH-95%RH non condensing Temperature Measurement Range: -40℃ to +80℃ Temperature Measurement Accuracy: ±0.5℃ Humidity Measurement Range: 0-100%RH Humidity Measurement Accuracy: ±3%RH Air Pressure Measurement Range: 600-1100HPa Barometric Pressure Measurement Accuracy: ±0.5HPa CO2 Measurement Range: 0-5000, 10000ppm（Default range 0-5000） CO2 Measurement Accuracy: ±20ppm PM2.5/10 Measuring Range: 0-1000ug/m³ PM2.5/10 Measurement Accuracy: ＜read numbers±10%(25℃) Output Signal: 485 signal Stability: ＜2%FS Nonlinear: <1%FS Response Time: ≤120S Wiring Instructions: Power Supply: thread color: Brown, instruction: V+; thread color: black, instruction: V- Communication: thread color:yellow, instruction:485A; thread color: blue, instruction:485B Application: Widely used in various environmental monitoring, can monitor a variety of elements, and has a variety of signal output methods, which is convenient for use in various environments, safe and reliable, beautiful in appearance, easy to install, and durable. Common problems and solutions The device cannot be connected to the PLC or computer Possible reason: 1) The computer has multiple COM ports, and the selected port is incorrect. 2) The device address is wrong, or there are devices with duplicate addresses (the factory default is all 1). 3) Baud rate, check mode, data bit, stop bit error. 4) The 485 bus is disconnected, or the A and B lines are reversed. 5) If the number of devices is too large or the wiring is too long, power supply should be provided nearby, add a 485 booster, and at the same time increase a 120Ω terminal resistance. 6) The USB to 485 driver is not installed or damaged.