It is essential that a sound level meter meets these standards if it is to be used for any important measurements, particularly those that involve the protection of workers (hearing protection) or any other legal purposes. The CEL240 meets the strict demands of ANSI S1.4, IEC 60651 and IEC 61672 and is provided with a Calibration Certificate at no extra cost, so you can make your noise measurements with confidence.
The graphical display gives the option of viewing the sound level as a simple number (shown to the left) or as a graph, clearly showing the variation of noise over time (see main image).
Unlike most sound level meters in this price range, the CEL240 uses the latest in digital technology - models using the older analog techniques tend to drift more over time and with temperature and air pressure changes. Sampling and digitizing the signal closer to the microphone ensures a much more stable sound level meter for repeatable measurements.
An AC output and optional DC output mean this meter can be connected to a level recorder, PC equipped with an A/D converter or integrated with another data logging system.
See Specifications tab for more details about the standards and noise measurement range.
The CEL240 Sound Level Meter is ideal for noise measurement applications that do not need automatic averaging (Lavg or Leq) or data logging. Here are some typical applications for this meter. If you are unsure then please drop us an email, we are happy to advise.
In the USA most companies follow the OHSA regulations, which demand the measurement of "Slow" Sound Level with "A" frequency weighting. The CEL240 provides these measurements, making it ideal for simple OSHA noise surveys.
Outside the USA many regulations demand the use of an integrating sound level meter. Even within the USA an integrating meter is advisable if the noise levels are not stable, as it will average out the variations in level, which is more reliable than averaging it by eye. Please see the Occupational Noise page for more information.
The standards for fire alarm testing usually demand the measurement of the "A" weighted "Fast" sound level. The CEL240 sound level meter provides this measurement.
Although not a data logging meter, the CEL240 has an AC output and an optional (free of charge) DC output, making it ideal for connection to a data logging system via a suitable A/D converter.
This meter meets the strict requirements of the international standards to Type 2 or Class 2. This may be adequate for environmental work, but often these measurement standards and the authorities involved will expect the use of a Type 1 or Class 1 (more accurate) integrating meter. Environmental monitoring usually requires automatic, repeating measurements of, for example, 15 minutes or 1 hour. Data logging is really a necessity.
For suitable environmental noise monitoring solutions please visit our Environmental Noise Page.
The CEL240 Sound Level Meter is controlled using just two buttons, one to the left and one to the right. The graphical display ensures that operation and the selection of options is as easy as possible.
Ensure 3 x AA batteries are fitted on press the red button to switch the sound level meter on. After a brief warm-period of just a few seconds, the meter will show the current sound level on the display.
The exact content of the display depends on how you set the meter up last time, as it remembers these settings for your convenience.
Some regulations and guidelines state that the meter's calibration should be checked before making measurements, and that you should keep records of these calibration checks.
Fit the Calibrator over the microphone and switch it on. The meter automatically detects the presence and correct fitting of the Calibrator and then starts the calibration process, which only takes a few seconds.
As the meter saves its settings, you should only need to do this occasionally. The left-hand button cycles through the following main settings:
|Display Type||Graph or numbers|
|Measurement Range||30 to 100 dB or 60 to 130 dB|
|Time Weighting||Fast, Slow or Impulse|
|Frequency Weighting||A or C weighting|
The right-hand button is used to change the current setting of any of these parameters.
You can now read the sound level from the display.
Press the reset button (right-hand button) to reset the max reading.
The CEL240 is a "general purpose" sound level meter and meets the international standards to Type 2 or Class 2. For any noise measurement that requires accurate, repeatable and comparable results, especially when used for hearing protection or other legal purposes, it is essential to use one that meets these standards.
|Measurement ranges||30 to 100 and 60 to 130 dB|
|Noise floor||< 33dB(A)|
|Time weightings||Fast, Slow, Impulse|
|Freq. weightings||A and C|
|Battery power||3 x AA Alkaline for >35 hours operation|
|External power||5V via USB Mini B socket|
|Dimensions||72 x 212 x 31mm, 245g|
|Tripod mount||1/4" socket|
|AC output||0.85V RMS @ FSD "A" weighted|
|DC output||0 to 3.3V DC for FSD on selected range (FOC option)|
|Operating conditions||RH: 5 to 90% (non condensing)|
|Temperature: 0 to 40°C|
|Atmos. pressure 65 to 108kPa|