If you are not familiar with the concept of the hypothetical measurement surface, more information can be found in the link below:
If you are not familiar with the concept of the hypothetical measurement surface, more information can be found in the link below:
Before defining the surface, we recommed that you read the corresponding standard to fulfill all requirements.
Ensure that there is no absorbing materials within the surfaces, and that the desired surfaces encloses the device under test (DUT) entirely. Some parts of the surface may be replaced by a hard wall/floor if the wall/floor is completely reflective (concrete is usually considered completely reflective).
Sources that does not emit a stationary spectrum may cause problems to the measurements.
In general, surfaces with curved planes are more difficult to measure than straight planes. A doubly curved surface like a hemisphere is not recommended for scanning. For Fixed point measurements, such surfaces may be selected, but careful distance measurements must be made to ensure correct measurement.
In the Nor150, go to Setup->Surface Definition to set up the surface. Surface Type decides the baseline surface, with corresponding Surface Dimensions. Surfaces and segments will be calculated based on these dimensions. By default, Nor150 splits surface into segments of maximum 1 m2. This may of course be changed manually.
The Nor150 will ignore all areas without any measurement in the calculation. Thus, if a segment is not measured, the area of that segment does not contribute to the total area, corresponding to an excluded surface.
In the current version of Nor150, only a cuboid surface is supporte directly. However, there is no hinder to use the post-processing functions in either Nor150 or Nor850 to edit the area of a segment.
To measure a standing cylinder surface, use for instance the Left and Right cubid surface for the cylinder part, and the Top for circle. In each segment, simply set the Width to 1, and enter your area calculation into the Height parameters (or vica versa). The Nor150 will then instantly provide the correct values for Sound Power and averaged Sound Intensity.
Another way is to set up a number of segments in one surface, not caring about the area. In the Nor850 software, either a Cylinder, Hemisphere or another surfaces may be defined in a new measurement, and the results can easily be copied into the corresponding visual representations in the Nor850 software from the Nor150 measurement after the measurement project is completed.