What is an accelerometer and Why do we need Accelerometers? What is the use of accelerometers? How does an accelerometer work? What are the types of accelerometers and how do they work? Piezoelectric accelerometer Piezo Resistive accelerometer This type of accelerometer has the same working principle as the piezoelectric accelerometer and the only difference is …
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What is a tactile sensor and what is meant by a tactile sensor A tactile sensor can measure any physical interaction with its environment. This sensor is capable to measure the parameters related to the contact of the sensor with an object. These sensors are designed according to the biological sense of cutaneous touch, which …
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Vibration meters use PNP transistors instead of NPN because they are inexpensive. The PNP transistors used by the circuits needed a negative bias voltage rather than a favorable bias voltage. Don opted for -18V. This was subsequently altered to -24V to give the transducer more linear range. At the period when the vibration meters were …
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The short answer is that when Don Bently worked on building solid-state versions of the eddy-current measuring system, he had a choice between using N-P-N or P-N-P transistors. Transistors were quite expensive at the time, so he chose the two least expensive: P-N-P The PNP transistors used by the circuits required a negative bias voltage …
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Introduction Sensors used to measure vibration come in three basic types: displacement, velocity, and acceleration. Displacement sensors measure changes in distance between a machine’s rotating element and its stationary housing (frame). Displacement sensors come in the form of a probe that threads into a hole drilled and tapped in the machine’s frame, just above the …
Definition Basically, vibration is oscillating motion of a particle or body about a fixed reference point. Such motion may be simple harmonic (sinusoidal) or complex (non-sinusoidal). It can also occur in various modes – such as bending or translational modes – and, since the vibration can occur in more than one mode simultaneously, its analysis …
The instruments which are used to measure the displacement, velocity or acceleration of vibrating body are called vibration measuring instruments. What is Machine Vibration? Machine vibration is simply the back-and-forth movement of machines or machine components. Any component that moves back and forth or oscillates is vibrating. A machine component may vibrate over large …
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AccelerometerAccelerometers are a piezo-electronic (crystal) device. A pre- loaded crystal is charged with current and as the crystal is compressed or de-compressed by vibration an output proportional to g’s (gravity) is provided. A “g” is equal to 9.80 meters/second2 or one (1) standard earth gravity. Accelerometers are normally used for high-frequency bearing cap vibration readings (Case/Bearing …
Measurement Type Only measurements of the same type can be compared. Bearing Cap or Case Vibration cannot be directly compared to Shaft Relative or Shaft Absolute and visa versa.1). Case Absolute Case or Bearing Cap Absolute is the measurement of the Case or Bearings Caps (Location of Transducer) motion relative to free space (or absolute motion). …