Condition monitoring is the process of monitoring a certain condition in machinery (such as vibration, temperature, etc.) in order to detect changes that may indicate a developing malfunction. Implementing condition monitoring allows maintenance to be scheduled and preventative actions to be taken to prevent future failures and subsequent unscheduled downtime. It is a crucial component of predictive maintenance.
什么是加速度计and why do we need accelerometers? An accelerometer is a device that can be used to measure vibration and shock. The accelerometers that are widely used are strain gauge and piezoelectric type accelerometers. An accelerometer is basically a motion sensor, it can measure the acceleration of an object. We can use …
A fotonic sensor is a fiber optical sensor and it can be used to do the displacement measurement. This sensor could do non-contact measurement and its working is based on fiber-optic principle and it can measure displacement, vibration, and surface condition. The operation of this sensor is simple, the part of the light which is …
An eddy current sensor is a displacement measurement sensor it can be considered as the improved version of an inductive proximity sensor. This sensor is composed of two coils one is the active or sensor coil and the other is the reference or balance coil. The eddy current sensor would measure the distance between the …
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 …
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 …
Why we use Negative Voltage in Vibration Measurement ?Read More »
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 …
Why we use Negative Voltage in Vibration Measurement?Read More »
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 or …
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 …
