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The PCE-S 41 Vibration Meter is battery powered and easy to use. This Vibration Meter can be used for detecting noise in machine components, such as gears, valves, vents, and pumps.
PCE-VS10 is a vibration meter, analyzer or sensor condition monitoring switch used to measure RMS and peak value of vibration velocity or acceleration piezoelectrically. This IP67-rated vibration monitoring switch features a red and green visual warning or alarm with programmable high pass and low pass filters.
PCE-VS11 is a vibration meter, analyzer or sensor condition monitoring switch used to measure RMS value, peak value and frequency domain (FFT) of vibration velocity or acceleration piezoelectrically. This IP67-rated vibration monitoring switch features a red and green visual warning or alarm with programmable high pass and low pass filters.
The vibraton meter PCE-S 42 is designed for listening to individual machine parts. The industrial stethoscope is used to perform maintenance and repair work. The use of an industrial stethoscope thus facilitates the interception of acoustic phenomena on bearings and motors to prevent failures.
PCE-VS12 is a vibration meter, analyzer or sensor condition monitoring switch used to measure RMS value, peak value and frequency domain (FFT) of vibration velocity or acceleration piezoelectrically. This IP67-rated vibration monitoring switch features an external USB port, 8-pin female connector 711 and programmable high pass and low pass filters.
Vibration meters from PCE Instruments are suitable for the regular recording of physical parameters 
such as vibration displacement, vibration velocity and vibration acceleration. Some vibration meters also have other measurement options, such as temperature measurement, speed measurement or determination of the bearing parameter. A vibration meter can be used to check the general condition as well as the condition of individual components (roller bearings, gears, etc.) of a machine. Trend developments of these parameters provide information about the impending damage. In this way, maintenance schedules or machine downtimes can be planned according to the condition of the machine. With this concept, a vibration meter increases the operational safety on the one hand, and at the same time increases the machine efficiency due to optimized machine running times and reduced downtimes. As mobile devices, vibration meters from PCE Instruments can be used autonomously, even in the difficult-to-access places. Depending on the vibration meter model, the measurement data can also be stored and subsequently evaluated with the help of the software.
When selecting a suitable vibration meter, it is important to pay attention to various aspects because of a large number of applications. These include measuring range, frequency range, the possibility of an FFT analysis, determination of the bearing parameter, mory capacity and other measuring functions. A frequent application is machine monitoring and machine evaluation according to DIN EN ISO 10816. This standard classifies various machine sizes according to drive power and assigns limit values to the individual classes, compliance with which guarantees safe, trouble-free operation. The standard also defines a number of specifications which vibration meters must comply with in order to ensure the measurement in conformity with the standard.
On the one hand, the standard specifies that the vibration velocity in mm/s is the relevant unit for machine monitoring. Furthermore, the frequency range to be covered is specified, which is between 10 Hz and 1 kHz. This means that a suitable vibration meter should be equipped with a corresponding frequency filter. All PCE Instruments vibration meters have these frequency filters, and depending on the vibration meter model the other useful machine monitoring functions are available.
Another important parameter in vibration monitoring is the speed, as comparable measurements and trend determinations must always be taken under the same operating conditions. Some vibration meters therefore have integrated, contacting or non-contacting speed sensors with which the speed can be determined directly on site. Since the defective components or bearings often generate increased friction values during the rotation, the surface temperature of a machine in the direct vicinity of the critical components can also provide valuable information on the machine condition. Some measurement data collectors therefore also have temperature sensors for determining the surface temperature. Another useful function is the FFT analysis. With this frequency evaluation, the vibration behavior of a machine can be analyzed in terms of vibration frequencies.
The vibration meter with the corresponding function shows the frequency spectrum of the machine on the display. Frequency peaks within the spectrum can indicate damage in rolling bearings. In order to be able to localize the errors more precisely, damage frequencies of the components at a given speed are required. Damage frequencies can be calculated using formulas, and information on this can often be received from the component manufacturer. Vibration meters with the functions described above can be found at PCE Instruments.
Machine condition monitoring is a key manufacturing maintenance task performed in production 
facilities around the globe. By identifying potentially problematic equipment based on machine diagnostics data, factories can take action to fix issues before equipment failures lead to costly production downtimes.
The PCE-VT 2700, PCE-VT 1100 and PCE-VT 204 vibration meter models primarily are used to measure vibration acceleration, vibration velocity and vibration displacement (also referred to as three-axis or X,Y,Z vibration) in manufacturing production machines and equipment. Using one of these PCE-branded vibration meter devices, a machine maintenance technician can assess the current condition of the equipment and identify the cause of any undesirable vibrations.
During machine vibration analysis, a graph of the vibration frequency spectrum is a useful visual aid. Increasing vibration is usually an indication that something is going wrong with the machine. Since vibration is connected to frequency, a frequency spectrum graph will reflect any increases or decreases in vibration.
The PCE-VM 25 vibration meter has a special function used for Fast Fourier Transform (FFT) analysis. For this reason, the PCE-VM 25 vibration meter is ideal for detailed investigations of machine bearing frequencies. The image on the right shows the PCE-VM 25 vibration meter in use to assess the vibration of a bearing in an industrial motor.
Vibration measurements can and should be taken not only to monitor the condition of the machine, but also to determine the effect of the machine's vibration on the machine operator. Vibrations may be permanent and continuous, or they may occur only from time to time, like impulses. Vibrations may be inertial, forced (i.e., a force acting on an object), relative or free (when displacement is involved). Depending on the position of the operator and his / her proximity to the equipment, he / she may experience whole-body or hand-arm vibrations.
If exposure exceeds the permissible limits, the operator may experience long-term problems with his / her fingers, hands, back and other body parts. Therefore, no matter what type of vibration is in question, the vibration should be evaluated according to its impact on the health and safety of the machine operator. If possible, changes to the machine itself (or to the amount of time the operator spends using the machine) should be made immediately to prevent or limit the operator's exposure to negative vibrations.
Vibration meters also are used to measure vibration in buildings. There are many factors that can contribute to vibration in buildings, such as the building's proximity to high-traffic roadways, railroad tracks, airports, quarries, construction sites and other heavy industrial areas. In addition, buildings can vibrate due to natural causes such as wind, weather and earthquakes, or due to the operation of internal building components like elevators and heating, ventilation and air conditioning (HVAC) systems. Vibration testing helps to determine what areas in a building are at the higher risk for vibration. Regular vibration monitoring in high-risk areas can provide property managers with advance notice of vibration-related structural issues.
Permissible exposure limits for vibrations are established by entities such as the International Standards Organization (ISO). ISO vibration regulations include:
The measuring accuracy of the vibration meter should be checked at regular intervals according to the established procedures. These checks are also referred to as calibration. Two standards have been defined for professional execution. According to these, a distinction is made between the so-called ISO calibration according to the requirements of DIN EN ISO 9001 and the more complex DAkkS calibration according to DIN EN ISO 17025. The standards differ, among other things, in the number of measuring points and the requirements for the measuring conditions.
When calibrating in an external laboratory, care must be taken to ensure that the target values tested there for vibration frequency, vibration acceleration, vibration speed and vibration displacement represent the values for which the vibration measuring device is used. A certificate is issued for each calibration carried out in accordance with the standard, in which all important information on the process and the results is noted. If the tested vibration meter does not achieve the expected accuracy, it is often possible to reset the device and then calibrate it again.
If the calibration is carried out in an external laboratory, the vibration meter is usually not available for measurements for several weeks. Therefore, the date of the calibration should be planned and organized in advance. Alternatively, it is possible to calibrate the vibration meter yourself using a suitable vibration calibrator. The vibration sensor of the measuring device is attached to the coupling surface of the calibrator and set in defined vibrations by it. The target values of these vibrations are then compared with the measured values determined by the vibration measuring device.
When selecting the vibration calibrator, the vibration values that can be generated are the most important criterion. Some device types can only generate a fixed value for frequency, acceleration, speed and displacement. With other calibrators, different vibration frequencies and vibration amplitudes can be set. The calibrator that can generate vibration frequencies between 16 Hertz and 1,280 Hertz and vibration accelerations between 1 m/s² and 20 m/s² is also suitable for calibrating the vibration meter for low- or high-frequency vibrations at several measuring points.
To ensure that a vibration meter works with the accuracy stated in the device specification, the devices should be checked regularly. Checking the measurement accuracy according to the specified rules is also called calibration. It can be done, for example, in particularly for this specialized external calibration laboratories. There are two different standards for calibrations, which differ, among other things, in the effort required and in the number of the measuring points. These are the ISO calibration according to the requirements of DIN EN ISO 9001 and the more demanding DAkkS calibration according to DIN EN ISO 17025.
The parameters that can be calibrated in a vibration measuring device include the vibration acceleration, the vibration velocity and the vibration displacement. The vibration frequency is also tested. When commissioning the calibration, it is important to ensure that the target values correspond to the range in which the operational measured values lie. A certificate is issued about the calibration carried out, which contains all the important information about the calibration procedure and values. Many calibration laboratories also offer to adjust the vibration meters if the accuracy specifications are not met, at a separate charge.
When calibrations are carried out in external laboratories, the vibration meter is often not available 
for the measurements for several weeks. Therefore, these calibrations should be planned and organized in advance. An alternative to this is to check the vibration meters in your own company with a vibration calibrator. For this purpose, the vibration sensor is attached to the coupling surface of the calibrator and set in defined vibrations. These target values of the vibrations generated by the calibrator are then compared with the measurement values from the vibration meter. The purchase of the calibrator can be particularly useful if several vibration meters are to be checked regularly on site.
An important criterion for selecting the vibration calibrator is the values of the vibrations generated. In addition to the calibrators, with which only one fixed value for frequency, acceleration, velocity and displacement can be generated at a time, there are also calibrators with which several vibration frequencies and vibration amplitudes can be set. With the calibrator capable of generating seven vibration frequencies between 15.92 Hertz and 1,280 Hertz and vibration accelerations between 1 m/s² and 20 m/s², special vibration meters for low- or high-frequency vibrations can also be tested for their accuracy at several measuring points. To ensure that the vibrations generated correspond to the defined range, the vibration calibrator must also be calibrated at regular intervals. Some of the devices have an internal test function that warns visually and acoustically in the event of deviations from the set value.
Often, the unusual vibration of the machines is an indication of uneven loading or bearing. The vibrations can be measured non-destructively with the vibration meter while the machine is running. By measuring and evaluating regularly, it is possible to detect irregularities early and take countermeasures before the major damage occurs. Many of the possible faults on the machines generate characteristic vibration components, so that the search can be narrowed down to these areas in the event of anomalies.
The values usually recorded as total vibrations result from several superimposed vibration frequencies. From the values of these broadband vibrations, the conclusions can already be drawn about imbalances, alignment errors and electromagnetic components. Often the manufacturers of machines also specify vibration values that must not be exceeded. Some vibration meters offer special evaluation functions for machine monitoring, for example, for rolling bearing control, for evaluation of machine vibrations according to DIN ISO 10816 and for FFT analysis.
The fast Fourier transformation (FFT) is a powerful tool for analysing vibration signals. The FFT can be used to determine the frequency spectrum of a time-discrete signal, that is, how strongly the various frequency components are represented in the signal. The FFT analysis is particularly useful for the vibration measurement because with the vibration meter it allows identifying the characteristic frequencies of machines or components that may indicate possible faults or wear.
The FFT is based on a mathematical algorithm that efficiently calculates the discrete Fourier transformation (DFT). The DFT decomposes a signal into a sum of sine and cosine waves with different amplitudes and phases. The FFT reduces the number of the computational operations required for the DFT by splitting the signal into smaller parts and transforming them recursively. The FFT is therefore much faster than the direct calculation of the DFT.
However, the FFT also has some limitations and challenges that must be considered when measuring vibration with the help of the vibration meter. For example, the vibration signal must have a certain length, which is a power of two, for the FFT to be applied. In addition, the signal must be multiplied by an appropriate window function to avoid spectral leakage, which is the broadening and smearing of the frequency spectra by side lobes. The choice of the window function depends on the signal to be analysed and requires a compromise between resolution and dynamic range.
The speed of a machine has a significant impact on the presence of unbalance errors. The higher the speed is, the more likely it is that such an error will occur. At a speed of 2000 rpm, an unbalance error can be visible at a high peak of the sine wave at 33.33 Hz.
To identify the unbalance error, it is important to understand the frequency with which it occurs. The unbalance error can be periodic or random and can be caused by a variety of factors such as material defects or poor alignment. It is important to perform periodic inspections with a vibration meter to detect and correct the presence of the unbalance errors before they become major problems.
The peak strength of the sine wave is an important factor in determining the presence of the unbalance error. If the peak protrudes significantly at a certain frequency, this is an indication of an imbalance. However, if the peak does not protrude significantly, this is an indication that the unbalance fault is not present. Therefore, it is important to always consider the peak strength when diagnosing machine problems using a vibration meter.
Loose foundations and loose components (looseness) on the rolling bearing are common causes 
of machine damage and failure. They can lead to increased vibration, noise, wear and heat generation. To prevent looseness, foundations and components should be checked and tightened regularly. In addition, the bearings should be properly aligned, mounted and lubricated. Looseness can be detected by various methods, such as visual inspection or vibration analysis using the vibration meter.
To avoid loose foundations and loose components, the following measures should be taken:
Poor alignment can cause uneven loading or deflection of the shaft, which in its turn can cause the bearing to loosen or shift.Misalignments are deviations from ideal alignment between two coupled shafts that can lead to increased vibration, wear, and temperature increases in the drive train. Alignment errors can have a variety of causes, including mounting errors, rotor sag, thermal expansion, or foundation movement. To avoid or correct misalignment, it is necessary to know the geometry and sign of the deviations in the shaft train and to use appropriate measurement and alignment methods. Alignment errors can become apparent in the vibration signal because of the sinusoidal oscillations with the rotational frequency and its harmonics. A vibration diagnosis with a vibration measuring device will therefore help to detect and correct the alignment errors at an early stage.
Rolling bearing damage can result from inadequate lubrication and sealing. If the rolling bearing is not adequately lubricated, metallic contact of the rolling elements can occur, which may result in increased wear, heat generation and eventual failure of the bearing. Similarly, because of the missing or inadequate seals dirt, dust and moisture may reach the rolling bearing and cause damage. Therefore, it is important to regularly check and, if necessary, improve the lubrication and sealing of the rolling bearings to prevent damage and failure due to inadequate lubrication and sealing.
Our Vibration Meter with FFT Analysis is the perfect tool for anyone who needs accurate and reliable vibration monitoring. With its state-of-the-art technology and easy handling, it is the ideal instrument for anyone working in industry, construction or research.
Some models of the vibration meters are equipped with an FFT analysis function that allows you to measure and analyse vibrations in real time. The FFT analysis is a powerful vibration analysis method that allows you to identify and quantify the vibration characteristics. With this feature, you can quickly and easily identify the cause of vibrations and take acts to correct the problem.
A PCE Instruments vibration meter is easy to use and has a user-friendly display that gives you all the important information at a glance. The vibration meter is robust and durable and can be used in the most demanding environments. It is also lightweight and compact, making it easy to transport and store.
Many of the PCE Instruments' vibration meters with FFT analysis are the perfect tools for anyone who needs accurate and reliable vibration monitoring. With its state-of-the-art technology and ease of use, they are the ideal measurement tools for anyone working in industry, construction or research. At PCE we are convinced that you will get the best possible results with our vibration meter with FFT analysis.
Vibrations are periodic deflections of materials or objects around a central rest position. Vibrations from nature and technology constantly affect us and our environment. Some of them we hardly notice, the others are disturbing or even dangerous. Vibrations can be generated and transmitted in different ways and superimposed with other vibrations. Vibration measurement can be used to determine precisely how strong a vibration is and whether it is displaced, amplified or weakened because of the changes of certain conditions.
We ourselves, other living beings, wind and weather are sources of more or less strong natural 
vibrations. For example, we generate vibrations when we shake, when we speak, sing or play music, or when we run or jump over a yielding surface. Professionals can measure many natural and engineered vibrations to obtain meaningful data. Vibration measuring technology helps in the prediction of earthquakes, for example, but also in the design and construction of safe structures, machinery and vehicles.
Some technical devices specifically generate vibrations for special applications. Vibrations can be used, for example, for acoustic or silent alarms, compaction, transport or separation of materials. Vibration alarms, vibratory rammers, hammer drills, vibratory plates, vibrating screens, and ultrasonic cleaning baths are widely used. The vibrations transmitted by the equipment should meet defined values to fulfil the intended purpose. To test the values, the equipment manufacturers use special vibration measuring technology in the development and quality assurance.
Vibration measuring technology can be used to study, measure and analyze natural and technical vibrations. The measurands of the vibration measurement include vibration frequency, vibration displacement, vibration velocity and vibration acceleration. Many devices for measuring vibrations offer extensive storage and evaluation options.
Some device types can record the measured values for the three spatial axes x, y and z separately. The other models offer connections for several external vibration sensors. Multi-channel devices offer the advantage that several points of a machine or a structure can be recorded simultaneously. This allows, for example, measures for vibration damping to be checked directly.
But also with a technical stethoscope, which only amplifies the existing machine noises, abnormalities can be detected and assigned. Through regular vibration measurement, the problems on important components can be detected at an early stage with a relatively little effort and eliminated.
The different types of equipment used in vibration measurement include:
In terms of application areas, the vibration measuring technology can be divided into measuring devices for machine vibrations, human vibrations, building vibrations. The devices are adapted to the field of application with regard to the measured quantities, the measuring range and the handling. Seismographs and seismometers for measuring earth vibrations are also part of the vibration measuring technology.
The bearings of the moving parts are among the most heavily stressed machine parts. Since bearing damage inevitably leads to the loss of efficiency or quality, early detection of the bearing damage ensures quick remedial action and helps to avoid downtime. The regular inspection of the bearings belongs to the scheduled preventive maintenance. One of the widely used methods for early detection of the bearing damage is vibration measurement. The more detailed the applied vibration measuring technology records and evaluates the vibrations, the more accurate statements can be made about the cause of the fault.
RMS (root mean square) of the total vibration level
The RMS value of the total vibration level increases with bearing damage. The measured value can be compared relatively easily with the reference values for the bearing.
Crest factor
The crest factor is the ratio of the peak value to the effective value. An increase in this value indicates early damage to the bearing.
Route measurement
Some vibration meters offer a route measuring function. This makes it easier to compare measurements at the same location with the data from the previous measurements. As a result, even some slight changes are noticed and the relevant points can be examined more closely at an early stage.
Machine monitoring is one of the most extensive fields of application of vibration measuring technology. Regulations for vibration measurement and the vibration measuring technology to be used can be found, among others, in:
DIN ISO 20816 Part 1 defines procedures for vibration measurement and assessment for machines. It regulates the measurements on rotating, non-rotating and non-oscillating components of complete machines. It also covers the measurements of absolute and relative radial shaft vibration. The specified evaluation criteria are decisive for both acceptance and operational control. The three basic vibration quantities, vibration displacement, vibration velocity and vibration acceleration, are defined and their limits named. The guide values are given for the evaluation of vibrations of non-rotating components on machines for which no special standard applies.
DIN ISO 10816 Part 3 assigns limit values for four evaluation zones to various machine variables differentiated according to drive power and mobility of the base. For vibration measurement according to this standard, the effective value of the vibration velocity in mm/s was defined as the relevant unit. The measured values that can be classified in zone A correspond to the new condition. Values of zone B are suitable for safe continuous operation, values of zone C only for short-time operation and values of zone D are classified as inadmissible. In addition, the standard defines specifications that the vibration measurement technology used must have. This ensures that measuring vibrations according to this standard leads to comparable and usable results.
ISO 2041 provides a selection of important terms and definitions that can be applied in the analysis of machine vibrations. These include, for example, the logarithmic method for determining the primary resonances, efficiency or torque vibration. With these definitions the understanding of vibration behaviours can be improved and at the same time supported in the development of new technologies to prevent machine failures. In addition, the terms and definitions can be used as a basis for establishing standards for measuring, analysing and evaluating machine vibration. The ISO 2041 guidelines thus provide a comprehensive list of terms and definitions that can be useful to both scientists and engineers in identifying and eliminating potential problems regarding machine vibration. In addition, the definitions can also be used in vibration analysis calculation programs to make the result of the analysis more precise and accurate.
Thus, ISO 2041 is a valuable resource that helps engineers to analyse vibration in machines more efficiently and quickly. Overall, it thus makes a significant contribution to preventing machine failures and increasing plant productivity. ISO 2041 also provides a comprehensive list of guidelines to help the engineers to select appropriate vibration analysis methods. For example, due to the guidelines the engineers can decide what type of measurement equipment is best suited to measure vibration in machinery. Similarly, the guidelines allow the engineers to have more precise control over how the measuring device is installed, what data should be collected, and what evaluation procedure is best for evaluating the measurement results.
Finally, ISO 2041 also helps to guide the engineers in the development of new technologies and measurement methods that will enable them to analyse and evaluate machine vibration more efficiently. Overall, therefore, ISO 2041 provides a comprehensive set of guidelines that enable the engineers to investigate machine vibration more quickly and accurately. This makes a significant contribution to preventing breakdowns and improving equipment performance. The application of ISO 2041 can also be useful in other fields such as mining or construction. Here as well vibrations are often generated and can present a serious risk to the workers’ safety. Using the guidelines and terms from ISO 2041, the engineers can gain an understanding of the causes and effects of vibration, which will help them to develop new technologies to reduce these hazards. As a result, ISO 2041 also contributes in creation of a safer and more productive work environment in other industries.
Overall, then, ISO 2041 is a valuable resource for the engineers, helping them to analyse and evaluate machine vibration more efficiently. The guidelines and terms from ISO 2041 thus provide a comprehensive set of tools that can enable the engineers to improve their understanding of the effects of vibration, and at the same time be very helpful in the development of new technologies to reduce potential hazards. It can also help to create a safer and more productive work environment in other areas where vibration plays an important role. One of the most important tasks in wind turbines is measuring and monitoring vibrations. A vibration meter can be used for this purpose to ensure that the wind turbine components are operating properly. The vibration meter is a specialized measuring device used to analyse wind turbine vibrations. It can help to identify the cause of vibrations and thus to improve the wind turbine performance.
The vibration meter is a valuable tool to monitor the operational performance of wind turbines. 
It is also important to check and maintain it regularly to ensure that all components are operating smoothly.
The vibration meter can help the operators to optimize the reliability and efficiency of their wind turbine. It can also help to detect problems early and to prevent the entire turbine from shutting down. In addition, it is also important that those who operate the vibration measurement equipment have the necessary knowledge and skills to ensure that each device is functioning properly. This will optimize the performance and reliability of the wind turbine.
The vibration meter can also be used to perform many other applications, such as machine vibration monitoring or detecting anomalies. This allows the operators to respond to potential problems ahead of time, and thus optimize the performance and reliability of their wind turbine. In addition, the use of the vibration measurement equipment can also help to reduce maintenance costs and make wind turbine operation safer and more efficient. Overall, the use of the vibration meter can assist in making the operation of a wind turbine more efficient and profitable.
PCE Instruments, one of the world leaders in vibration measurement, provides comprehensive solutions and services to customers in diverse industries. We specialize in the design and manufacture of the vibration measurement instruments suitable for accurate and reliable measurement results in a wide range of applications. Our extensive product line includes both portable and stationary vibration measurement devices. These products are compatible with professional software applications, accessories and a wide range of sensors for specific measurement tasks.
Our expert technical knowledge and experience have enabled us to develop solutions that provide fast, accurate and cost-effective vibration measurement. We also offer a range of training programs to help you to fully realize the potential of our products. No matter what field you are in or how complex your requirements are, PCE Instruments has the solutions you need. Our goal is to help you to achieve fast and accurate measurement results. Contact us today to learn more about our vibration measurement equipment and solutions. We'll be happy to help you to find the right one for your measurement needs.
PCE Instruments also offers around-the-clock customer support. Our customer service team is always available to help you with any questions or issues you may have. Our goal is to ensure that you receive the best support possible. We are also available for maintenance, repair, and calibration of your instruments. Our service team is highly trained to ensure you always have access to the latest updates and software tools. This is an important step towards faster, more accurate measurement results. Our research and development team are continually working to improve our products to meet the changing needs of our customers.
We are proud to have developed one of the most comprehensive and adaptable vibration measurement systems available today. Our products are suitable for a wide range of industries and meet the highest standards of precision, reliability and ease of use. We'd love to help you to complete your measurement tasks quickly and efficiently. Contact us today if you would like to learn more about our vibration measurement equipment. We look forward to being able to help you.
Our vibration meters are designed to be used in a variety of environments and applications around the world. We ensure that our products and solutions meet the highest standards of quality precision and reliability. We are always available to help you to select the right instrument. Our customer service team is always available to provide advice and assistance to ensure you receive the best product experience. Contact us today if you would like to learn more about our vibration measurement equipment.