LMS Test.Xpress Rev 2B supports easy ISO certification and acoustic troubleshooting

On top of its already extensive set of certification testing and troubleshooting capabilities for everything from disk drives and production lines to heavy equipment and power tools, LMS Test.Xpress Rev 2B extends its acoustical certification testing into the domains of declared sound power, acoustical intensity and source localization.

Supporting ISO standards is nothing new for LMS Test.Xpress. The previous version, LMS Test.Xpress Rev 2A already supported pressure-based sound power measurements based on the ISO standards: ISO3741, ISO3744, ISO3745 and ISO3746. This new version automates the formerly cumbersome ISO process associated with so-called "declared sound power" calculations and certification.

 "We hard-coded the necessary ISO certification standards right into the software. All the operator needs to do is push a button and the required documentation is printed. Customers donÌt need an ISO certification specialist. LMS Test.Xpress Rev 2B does the work for them," explains Frank Demesmaeker, LMS Test.Xpress Product Line Manager.

Declared sound power is a statistical combination of several sound power values taken over different units, multiple operators or operation modes. The applications are numerous, ranging from production line quality control to combining different operation modes into a single sound power value for heavy equipment like a bulldozer. For hand-held power tools, it is even possible to incorporate the effect of different operators and material properties.

Working with a grid-based user interface, a simple click on a cell will start the ISO sound power measurement for a specific test mode or unit. When the whole grid is measured, the declared sound power value is automatically calculated.

Besides the above-mentioned pressure-based ISO standards, LMS Test.Xpress can handle sound power based on intensity probe measurements required by the ISO9614 standard. Both the point-by-point method (ISO9614-1) and scanning method (ISO9614-2) are supported. Different probe types are available including automatic correction for the used spacer as well as dedicated intensity calibration routines. 

While measuring, a "shoe-box" geometry display shows the different surfaces and sub-segments and clearly indicates the time, segment status, data quality and overload occurrence as well as intensity flow to avoid errors. Users can check the time variability of the acoustic intensity as well as intensity as a function of time.

Like the other ISO certification processes, this ISO-based measurement is designed to be extremely easy to use while remaining ISO process compliant. To do this, users follow a simple toolbar user interface through the completely automated procedure from measurement to reporting. For extra security, the process is password protected.

Market regulations today impose extremely stringent maximum noise levels. To support troubleshooting, LMS Test.Xpress Rev2B offers a dedicated source localization module to support sound source identification and localization according to sound intensity measurements.

"Today, the regulations are so strict that engineering teams need to go back and look at the core characteristics of the design. Just adding a bit of dampening insulation wonÌt work any more," stated Frank Demesmaeker.

For these types of measurements, results are displayed as one or multiple surfaces of the Ïshoe-boxÓ geometry, either as overall levels or in a specific octave band. These graphics can easily be exported to Microsoft Excel or Microsoft Word for source ranking. Placing a digital image of the test object over the contour plots provides immediate feedback regarding the location of noise sources.

"With this specific solution, LMS is helping all types of customers - no matter how big or small - find the root causes of acoustic behavior in an easy and straightforward manner," concluded Frank Demesmaeker.