A pioneer in technology measurements, Endevco has supplied excellent solutions to aerospace, automotive, marine, medical industries and engine testing.
Advanced microphones, such as those developed by Endevco, are used for the measurement of high-intensity sound (> 95 dB SPL). Typical applications include near-field measurements of jet aircraft engines, testing and evaluation of rocket motors, and other similar environments. While accelerometers measure vibration of a structure, microphones measure airborne sound (or pressure). Since sound is produced by mechanical vibrations, understanding the mechanical structure producing the vibrations... Read Full Story
Basic application parameters often drive which type of device to select. Using Endevco as an example again, the are limited to 150g or less (one measures ±2g, full scale). But it is also important to keep in mind that Endevco Microtron® devices have 20,000g survivability. This extreme overrange capability is the result of the unique design of the Endevco Microtron accelerometer . VC devices, with their high sensitivity, are well suited for testing automotive suspension systems, measuring... Read Full Story
The need to measure shock phenomena has become a very important aspect in recent years. In the past much shock information has been in the form of whether a piece of equipment will withstand specific shock as produced by shock machines . But these machines are not necessarily accurate; therefore the chance of malfunction when those tested sensors are subjected to specific fields. In present flight and missile field, size and weight have become very important factors so that large safety... Read Full Story
Piezoelectric accelerometers are the first choice for most vibration measurements since they have a wide frequency response, good sensitivity and resolution and are easy to install. There are two subdivisions of piezoelectric accelerometers which include the basic charge-mode accelerometer and the voltage mode Internal Electronic Piezoelectric (IEPE) types. IEPE Piezoelectric In recent years, the IEPE type has become the most commonly used accelerometer type. IEPE sensors are often sold under... Read Full Story
Mounted resonant frequency is the point in frequency in the accelerometer’s frequency response where the accelerometer outputs maximum sensitivity . It is specified in units of hertz (Hz). Typical accelerometers exhibit a mounted resonant frequency above 20 kHz, although some show as high as 90 kHz. As the name implies, it is the result of the natural resonance of the mechanical structure of the accelerometer itself. [Certainly if the resonance of the accelerometer were measured in “free... Read Full Story
The ENDEVCO® Model 8511A is a rugged, piezoresistive pressure transducer for high pressures. It has a 3/8-inch mounting thread and is available in ranges from 5000 to 20 000 psig. ENDEVCO pressure transducers has an active four-arm strain gage bridge diffused into a sculptured silicon diaphragm for maximum sensitivity and wideband frequency response. Self-contained hybrid temperature compensation provides stable performance over the wide temperature range of 0°F to 200°F (-18°C to +93°C... Read Full Story
A piezoelectric transducer can be considered a small capacitor which is also a coulmb generator. In order to operate into the usual readout instrumentation, such a device requires specialized matching electronics . A cathode follower or high input impedance voltage amplifier limits maximum cable length between transducer and amplifier (long cable result in poor signal-to-noise ratios; frequency response depends on amplifier input impedance, and cable change require system recalibration... Read Full Story
Pressure measurement plays an important role in the development of many aerodynamic structure such as wings, turbine and propeller blades. Theoretical data need to be checked and calibrated with actual measured data for optimization of designs performance. The sensor must be employed in such a way as to measure but not to disturb the flow patterns over the surface of interest. Measurement of pressure and pressure induced loads on aerodynamic structure presents special challenges, the sensor... Read Full Story
Engine manufacturers have been very effective in designing DLN (Dry Low NOx) gas turbines that optimize and take benefit of lean-premix design combustors. However, the purpose is to maintain a very narrow lean stability limit. Under these conditions, the machine is more vulnerable to serious incidents like flame-out, instabilities or flashback induced by pressure waves causing potentially serious damage to the engine. Changing conditions, such as fuel quality or ambient conditions, can... Read Full Story
An accelerometer is a device for measuring acceleration and gravity. Single- and multi-axis models are available to detect magnitude and direction of the acceleration as a vector quantity, and can be used to sense orientation, vibration and shock. Accelerometers are increasingly present in portable electronic devices and video game controllers. Accelerometers with integral electronics have a maximum output voltage determined by the circuit design and the input voltage. The maximum output for... Read Full Story
