DC9-30V RS485 Noise Sensor Sound Dosimeter Decibel Tester Transducer for Machinery Vehicles Ships Item Type: Noise Sensor Product Length: Approx. 292mm / 11.5in Power Supply: DC 9-30V Output Form: RS485 Measurement Range: 30-130dB (A) Sensitivity: -38±3dB (or 12.6mv/Pa) Resolution: 0.1dB Accuracy: ±3dB, calibrated under the condition of environmental temperature 23±5℃, frequency weighting compliant with for IEC 61672 type 2 standard, with input sign of 94dB (1kHz). Frequency Range: 20Hz to 12.5kHz Response Time: 200ms, time response simulates the response time of the human ear. Calibrator: for B and K, multi function sound calibrator, model 4231 Microphone: Polarized microphone Directivity: Omnidirectional Microphone Size: 0.5 inches Load Capacity: Impedance ≤350Ω for current output when powered by DC12V, ≤900Ω for current output when powered by DC24V, ≥1KΩ for voltage output Maximum Power Consumption: 500mW Material: Aluminum alloy Working Environment: Temperature -40℃ to 80℃, humidity ≤100 percent RH non condensing Safety Level: IP55 Weight: Approx. 418.00g / 14.74oz Troubleshooting: The meter displays incorrect values at output. The correct data cannot be obtained because the cable connection is faulty or the communicating serial port is faulty. Check whether the cable connection is correct and secure, whether the serial port is occupied, and whether the serial port settings are correct. The wire sequences are: Wire color Output sign RS485 Red Power supply positive Black A+/TX Yellow B-/RX Green Power supply negative