NoiseSensor Outdoor Microphone
Integrate noise measurement with a 4-20mA current loop
The MK:427 Noise Sensor is a self-contained outdoor noise monitor that connects directly to process measurement and control systems, such as SCADA, with unparalleled ease.
Unlike a conventional Sound Level Meter, the Noise Sensor simply converts the noise level in decibels into an industry standard 4-20mA output.
The pure-analogue electronics are highly reliable and operate without any user intervention. No specialist acoustic knowledge is required – simply power-up the Noise Sensor and the measured noise level is continuously fed to the output. With the 4-20mA output, very long cable lengths can be used without reducing the accuracy of noise measurements.
Benefits at a glance
- Fully weather protected outdoor noise measurement microphone
- 4-20mA current loop output for simple integration with data logging systems
- Purpose designed to allow noise measurement information to be integrated into existing data logging systems such as SCADA
- Optional electrostatic calibration system for automatic and regular verification of system performance
- Available with either a 1m length (MK:427/S) or 1.6m length (MK:427/L)
- Simple mounting and installation for quick deployment
The unit is a fully weather protected with the same mechanical and acoustic performance as the Cirrus MK:426A, an outdoor noise measurement microphone that has been field proven over many years in harsh environments worldwide.
The MK:427 provides a simple 4-20mA loop output that is directly proportional to the noise level at 0.1mA/dB. This output level is ‘A’ weighted and is factory set to either Fast or Slow time weighting.
An optional electrostatic calibration system can be fitted to provide automatic and remote calibration of the system using a simple +5v trigger. This allows the performance of the instrument to be verified where it is installed in inaccessible locations.
The Noise Sensor incorporates a 1.2 meter microphone pole, allowing the microphone to be positioned in free space, well away from any obstructions. A version of this unit, the MK:427/2 has a shorter 50cm microphone pole.
A variety of mounting methods make the device simple to fit on any building or structure. The sensor hardware is based on a well-established Cirrus design that has been proven in harsh weather conditions around the world for many years.
To ensure that the sensitive microphone transducer is always in good condition, it is fitted with an electrostatic actuator calibrator. This can be used to make regular fixed-point calibrations of the entire measuring chain, thus verifying data integrity.
The device can be set to measure Fast or Slow time-weighted Sound Pressure Level with “A”, “C” or “Z” frequency weighting to Class 1 standards.
A unique prescaling calibration system allows any 65dB span in the range 20 to 130dB to be selected by the user.
MK:427 NoiseSensor Microphone
