To maintain signal integrity in an automatic test system requires:
Many accelerometers used for measuring vibration include a built-in preamplifier to transform the high impedance charge output of the piezoelectric sensor into a low impedance voltage signal, typically 100-300 ohms, that can be transmitted over longer distances. To power this preamplifier, many VTI Instruments products provide an interface that complies with the Integrated Electronics Piezo Electric, or IEPE standard. Using this standard interface ensures that you can connect sensors with an IEPE interface to a VTI instrument and get good results.
A question that we often get is whether or not the IVI instrument drivers that we supply with our VTI Instruments products are compatible with Linux. The reason for this question is that many users prefer to have complete control over the software of their test system. And as a result, prefer to use Linux over Windows as their test system’s operating system. For users of LXI instrumentation, the question becomes whether or not the IVI instrument driver that comes standard with their LXI hardware work in Linux.
When performing functional tests, keeping test times as short as possible is often a critical requirement. Time is money, after all. One way to reduce test times is to reduce the latency in setting up signal switch paths, stimulus devices, and measurements. These can all have a significant impact on the overall time it takes to complete a full functional test of a particular DUT.
Calibration is not an option. While today's instruments are more accurate and drift less than previous generations, you still need to periodically check and calibrate your equipment. The way you do this, however, is changing.
In the past, manufacturers would recommend calibration intervals. A digital multimeter manufacturer might, for example, recommend that you calibrate the instrument once a year. When that year was up, you sent the DMM to your company's cal lab or to a third party.
That paradigm is changing. The current trend in metrology is not to blindly follow a manufacturer’s stated calibration interval, but to determine your own interval based on how much each instrument drifts over time and how much risk you're willing to take.
VTI Instruments' new RX0424 IEPE/Voltage Instrument is a cost-effective new device that is ideal for measuring acceleration forces and sensing static and dynamic movement or vibrations. Fully-integrated IEPE current excitation and tachometer input channels further enhance the instrument’s utility and functionality.
The automotive market is a highly competitive and complex business. In order to be competitive, vehicles must not only offer comfort and top-notch features at a cost-effective price but also ensure passenger safety. Long before any new model goes into mass production, a long series of sophisticated tests and validations are required at various stages to ensure that the vehicle meets all governmental standards and company performance standards.
Vehicles are often operated under test conditions for weeks or months, which requires logging and archiving massive amounts of data. In addition, in-vehicle tests often require the use of portable test systems, which are ideally compact, rugged, light in weight and free standing. Given the limited space within the vehicle, they typically must operate wirelessly with no connection to a computer. These in-vehicle datalogging systems must be compatible with a wide array of sensors.
A jet engine is the very definition of “mission-critical.” A critical failure could cause a serious accident that endangers hundreds of lives. To prevent this from happening, manufacturers perform extensive testing on jet engine components, systems, and manufacturing processes.
Jet engine tests involve subjecting the unit under test to extreme temperatures, jets of water, simulated hail, severe vibration, and other harsh conditions. Sometimes test engineers even slam chicken carcasses against engines to simulate bird strikes. These tests can be very costly and take years to develop. Engineers must measure many different parameters during these tests, including temperature, flow, pressure, rotation, strain, and vibration.
Data acquisition systems are at the core of many automatic test systems and industrial control systems. They make various types of physical measurements, such as temperature, pressure, flow, strain, position, and speed, using electronic equipment. The data collected is usually sent to a computer for analysis and display.
Interchangeable Virtual Instruments (IVI) is a standard for instrumentation drivers that is designed to reduce the time and effort needed to integrate measurement devices into new or existing systems. It does this by providing a standard application programming interface (API) that defines common measurement functions. This is, in turn, provided by a standard set of shared components that must be used by all compliant drivers and ancillary software. These components provide services to drivers and driver clients that need to be common to all drivers.
