The MK440 NoiseSensorLITE is a trimmed down version of the MK427 NoiseSensor noise monitor. Meeting the sound level meter standards to Type 2, it is intended for monitoring around industrial and construction sites, although there are many other noise monitoring applications for which it fits the bill.
The NoiseSensorLITE converts the 'A' weighted sound level into a 4-20mA current loop output, which is ideal for linking to existing process control and monitoring systems, such as SCADA or DCS.
As the microphone and noise processing technology is all contained within the MK440 the installation process is simple. There is no configuration needed, just electrical connections for power and for the current loop output.
The noise sensor would usually be installed at a location close to where the environmental noise is most likely to have an impact. Try to mount away from obstacles and walls that may reflect the noise, and away from any other noise source. The microphone should be at least 1.2m above ground level.
The noise sensor requires between 12VDC and 24VDC power and connection for the 4-20mA output.
An optional wall mounting kit, order code BP440, is available. See More Options in the pricing section above.
Full installation instructions are available in the Installation and User Guide on our Technical Support site.
The output from the NoiseSensorLITE is 4-20mA current loop as used by many process control and monitoring systems. The sound level in dB(A) is mapped to the 4-20mA range.
The standard MK440 has a measurement range of 34 to 104 dB(A), but other ranges are available on request. With all ranges the current is proportional to the output:
Iout ∝ 0.1 mA/dB
Connection for current loop and power is made using the 10m (32ft) cable that is included. Different length cables can be fitted and the wiring details are covered in the Installation and User Manual.
The 4-20mA current loop output is generally preferred for control and monitoring systems as the level and accuracy is not degraded by the length of cable (up to a limit). However, if your system needs a DC level then the current can be easily converted.
To convert the 4-20mA output current to a DC voltage output, connect LOOPOUT to the Loop Power Input Ground via a 100Ω resistor for a voltage across the resistor of 10mV/dB.
If you need a noise monitor for installation in a hazardous or potentially explosive atmosphere then the MK440 has FM approval.
The MK440 NoiseSensor LITE has the following approvals and FM certification:
Technical specifications for the MK440 NoiseSensorLITE noise monitor with 4-20mA current loop output.
|Output Type||Sound level in 4-20mA loop|
|Frequency Weighting||'A' (factory option for 'C' or 'Z' weighting)|
|Time Weighting||Fast (factory option for Slow response)|
|Measurement Range||34 to 104 dB|
|(factory options: from 24-90 dB to 74-144 dB)|
|Current Loop Out||Iout = 0.1 mA/dB|
|Power Supply||12 to 24 VDC|
|Cable Entry||1/2" NPT or M20 Gland|
|Cable Length||10m supplied|
|Operating Temp.||-10°C to +50°C|
|Protection||Enclosure: IP65, Microphone: IP54|