Noise Sensor Transducer Device Inside Outside Sound Dosimeter RS232 Decibel Tester DC9-30V Item Type: Noise Sensor Product Size: Length: Approx. 292mm / 11.5in Power Supply: DC 9-30V Output Form: RS232 Measuring Range: 30~130dB (A) Sensitivity: -38±3dB(or 12.6mv/Pa) Resolution: 0.1dB Accuracy: ±3dB, at ambient temperature 23±5℃, frequency weighted according to IEC 61672 type 2 standard, calibrated at input signal 94dB (1kHz) Frequency Range: 20Hz to 12.5kHz Response Time: 200ms, the time response simulates the time response of the human ear Calibrator: Multi function sound calibrator, model 4231 Microphone: Electret microphone Directivity: Omnidirectional Microphone Size: 0.5in Load Capacity: Current type output impedance ≤350Ω for DC12V power supply; Current type output impedance ≤900Ω, voltage type output impedance ≥1KΩ for DC24V power supply Maximum Power Consumption: 500mW Material: Aluminum alloy Working Environment: Temperature -40℃ - 80℃ Humidity: ≤100%RH No condensation Protecting Class: IP55 Weight: 418 g / 14.7 oz(approx.) 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 Line Sequences Are: Red: Power supply positive Black: Connect to RX on pin 2 of serial port Huang: Connect to pin 3 TX of the computer serial port Green: Power supply negative