What Is A Hammer Test Or Hammer Impact Test?
A Hammer Impact Test is also known as a Modal Test, Impulse Test, Tap Test, Bump Test or, simply, a Hammer Test. It is a method of testing that allows…
A Hammer Impact Test is also known as a Modal Test, Impulse Test, Tap Test, Bump Test or, simply, a Hammer Test. It is a method of testing that allows…
Prosig have welcomed 2010 with the official launch of their PROLOG data acquisition controller.
PROLOG is a controller that will allow remote, unattended or standalone operation of a P8000 system. In normal operation a P8000 data acquisition system is connected to a laptop or PC and data is stored, in real-time, on the computers hard drive via the USB 2.0 interface. This configuration provides a robust, high speed data capture environment. However, there are situations where it is not practical to keep the laptop connected. In some cases the environment may be suitable for the P8000 unit, but not for some of the more fragile components in a laptop. In other situations it may be desirable to have the measurement system in one location, whilst the operator may be positioned some distance away. The PROLOG unit is designed to address both of these requirements.
The following note describes measuring exhaust noise using a Prosig P8000/DATS system for the refinement of an automotive muffler design for a major after-market exhaust manufacturer in Europe. The particular vehicle under test was required by local legislation to have an overall radiated noise level of less than 70 dB. When tested, the vehicle was found to be producing 71.8 dB of radiated noise. The design of the exhaust system clearly needed to be reviewed and modified. (more…)
Accurate measurement of a signal depends on the dynamic range and the overall level of the data acquisition system. The overall level setting may be thought of as determining the largest signal that can be measured. This clearly depends on the present gain setting. That is the overall level is related to the gain. Clearly if the overall level is too small (gain too high) then the signal will be clipped and we will have poor quality data. The dynamic range then tells us that for the given overall level what is the smallest signal we can measure accurately whilst simultaneously measuring the large signal.
In a very simple sense suppose we have an artificial signal which consists of a sinewave at a large amplitude A for the first half and that this is followed by a sinewave with a small amplitude a for the second half. We will set the gain (the overall level) to allow the best measurement of the A sinewave. The dynamic range tells us how small a may be so we can also measure that without changing settings.
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