Vibration Research

Frequently Asked Questions

For a quick, handy cheat sheet, download a copy of our VR9500 Quick Start Guide now! Or download a copy of the VR8500 Quick Start Guide.

Click on a heading to see a list of questions related to that topic.
Click here to see quick tip videos or our gallery of archived webinars (for registered users).


How often do I need to calibrate my Vibration Research Corporation system?

Annually. The system comes calibrated from the factory, so you don't need to calibrate it again until the due date on the calibration certificate.

What are the options for calibrating my VR8500 or VR9500 Revolution controller?

Please see our calibration page.

What are the options for calibrating my VR7500 controller?

You have two (2) options:

  1. With the instructions in the VibrationVIEW operators manual, you can manually calibrate the model 7500 controller in your own calibration laboratory.
  2. You can send your model 7500 controller back to VR for calibration. Please contact us for information and pricing.

My accelerometers need recalibration, what do you suggest?

We suggest that you send your accelerometers in directly to the manufacturer for recalibration. If you purchased your accelerometer directly from VR and are not sure who the manufacturer is, feel free to contact us for that information.


How many channels does the VibrationVIEW system support?

The VR7500 system supports up to 8 channels and the VR8500 and VR9500 Revolution systems support up to 32 channels.


How can I get a demonstration of a Vibration Research controller?

Call Vibration Research Corporation at (616) 669-3028, email us at or talk to one of our representatives.

Dynamic Range

How can I view the dynamic range of the controller?

Dynamic range on a vibration controller is an important and often misunderstood concept. Many controllers specify input dynamic range or output dynamic range or they may just specify dynamic range. To cut through all the specifications you can run a simple test with the controller, and view the total system dynamic range. To run this test, create a random profile with a section of the profile reduced to nothing. Then, by observing the actual level of the profile, you can determine the random dynamic range.
The Chinese government has a dynamic range test, test specification JJG 529-88, that they use to specify the dynamic range of systems. This test can be run on an entire shaker system to determine its dynamic range or on just the controller "looped on itself" to determine the controller's dynamic range. This test has the following breakpoints:

20 Hz

-40 dB

80 Hz

0 dB

300 Hz

0 dB

350 Hz

-40 dB

350 Hz - 500 Hz

no energy

500 Hz

-40 dB

600 Hz

-20 dB

650 Hz

-20 dB

700 Hz

0 dB

750 Hz

-20 dB

800 Hz

-20 dB

1000 Hz

0 dB

1500 Hz

0 dB

2000 Hz

-20 dB

When this test is run on Vibration Research Corporation's controller, VibrationVIEW, a dynamic range of 90+ dB is demonstrated! Many controllers claiming 80 dB of dynamic range show only 50 dB or 60 dB when running this test. Lack of adequate dynamic range may cause system problems when controlling a fixture with a large resonance.

See the figure below for dynamic range explanation.

Emergency Stop Button

Why is the emergency stop button an important safety feature?

The emergency stop (e-stop) button provides further safety measures for lab personnel as well as testing equipment and products under test. It provides lab personnel with a quick way to stop a test without putting a transient "shock" into your test product. See this PDF document for more important e-stop button details.

How do I install my emergency stop button?

If your e-stop button was shipped with your controller, follow these instructions:

  1. Plug the Phoenix connector into the back of your I/O box, as shown here
  2. In VibrationVIEW, go to "Configuration...Remote Inputs" on the toolbar
  3. Click on the eighth (8th) drop down box and select "Emergency Stop Button". Then press OK.
    For printable instructions, click here.

If your e-stop button was shipped after you received your controller, click here for installation instructions.

Extremal vs Notching

What is the difference between Extremal and Notching?

Click here to view a PDF which explains these options

Hardware Registration

Why should I register my hardware and where can I do so?

When registering your hardware, you will verify your VR9500 Revolution controller's 1 year Upgrades & Support Agreement and 3 year hardware warranty. You may register your system online (click here).

Help & Support

How can I use Network Logging for technical support?

Network Logging is a feature that has been added to allow the Vibration Research technical support team to better diagnose communication issues you may have between your controller I/O box and your pc. To learn how to use this feature, click here.

Key Problems

VibrationVIEW tells me my key has expired. What shall I do?

If your controller computer is connected to the internet, go to Help...Check for Key Update in the VibrationVIEW menu.
Upgrade to the most current VibrationVIEW software version (click here).
Verify that your controller invoice has been paid.
Verify that your master controller is set as Channels 1-4 in Configuration...Hardware menu
If you are still having problems, please contact Vibration Research at or call +1-616-669-3028.

VibrationVIEW tells me no key is found on my 7500 system. What shall I do?

Make sure the key is plugged into the parallel port. Then make sure the parallel port is being recognized by Windows.
If you are still experiencing problems, call Vibration Research at +1-616-669-3028.


Where can I get an electronic copy of the manual?

The manual is on the CD in the Manuals directory in Word (.doc) and .pdf format. The Word version requires Microsoft Word or the MS Word Viewer. The .pdf version requires the Adobe Acrobat Reader.

The manual is also available online via the software updates page.

I can't open either type of electronic manual. What shall I do?

If you purchased your computer from Vibration Research Corporation and have version 2.1.18 or greater of VibrationVIEW the Word Viewer and Acrobat Reader should be installed. The MS Word Viewer and Acrobat Reader are both on the VibrationVIEW version 2.1.18 and later CD. Run R:\installer.exe (where R is the letter of your CD-ROM drive and follow the on-screen instructions.  Otherwise, follow these links:

Word Viewer

PC Specifications

What kind of PC do I need to run VibrationVIEW?

See the PC Specifications document here.

Power Outage

What happens if I lose power to my computer, controller, and shaker amplifier?

All is not lost. The recent versions of VibrationVIEW store data in a Temp folder, even if you do not have "Save Data" checked on the Data tab in Settings. This auto-save Temp file is saved at the same time interval that is set on the Data tab, even if the box is not checked.
To retrieve this data, go to the Temp directory where it is stored and select the last saved data file (named with a time-stamp). The default is C:\Documents and Settings\user\Local Settings\Temp.
Look at the time history or print a report to find out how long the test had been running. This will give you a starting point to continue with the test.
You may have to reset your amplifier prior to restarting the test.

What happens if I lose power to my shaker and controller, but have U.P.S. back-up on my p.c.?

You will see a test stop code message "Lost Contact with IO box s/n".

You can resume the test at this point (assuming power is restored to the amplifier and controller). Otherwise, the data can be manually saved by clicking the Save Data button.

Or, you can retrieve the data by going to the Temp directory where it is stored and selecting the last saved data file (named with a time-stamp). The default is C:\Documents and Settings\user\Local Settings\Temp.

Also, if you have data set to automatically save at the End of Test, then you can be sure all information will be saved up to the time the communication error occurs.
You may have to reset your amplifier prior to restarting the test.

What happens if the accelerometer cable breaks?

The controller will "gently" stop the test to prevent any transients from going through your shaker. There will be a stop code that will read something similar to Max acceleration on ch X.

Random Import

How do I generate an automatic Random Import profile?

Clicking the "Import" tab on the Random Test Settings dialog box accesses this dialog box

Use this dialog box to automatically generate a spectrum profile from input data. The input can be a set of frequency/amplitude breakpoints, a time/acceleration history stored in a text file, or can be measured from an analog input channel on the VibrationVIEW I/O unit.

To input data from a file, perform the following procedure:

  1. Select the input type using the radio buttons directly below the "Input file" button
  2. Click the "Input file" button to select the file from which to read the data. The file will be scanned, and the dialog box will be updated to reflect the contents of the file
  3. Set the sampling rate, number of header lines, the column number for the acceleration data, and the acceleration units used in the file
  4. Select the spectrum generation method. The import procedure divides the file into 1024-sample blocks, computes the spectrum for each block, and then combines them according to the selected method. "Average" will average all of the spectra together using a uniform average. "Peak hold" will extract the peak values over all of the blocks at each frequency
  5. Click the "Create Table" button to process the file and create the frequency/amplitude breakpoint table from the input file

To input data from an analog input channel on the VibrationVIEW I/O unit, perform the following procedure:

  1. Select the "Record from inputs" radio button, as shown in the figure below
  2. Select the spectrum generation method. "Peak hold" will keep the peak acceleration level seen at each frequency. "Average" will perform an exponentially-weighted average of the input data, with the amount of averaging determined by the Average XX frames parameter. Higher averaging values will result in more averaging and therefore smoother spectra
  3. Select the input channel, mV/G setting and desired sampling rate. The sampling rate should be 2.6 times the highest desired frequency to be used in the test. An anti-aliasing filter on the input will remove the higher frequency components from the signal
  4. Connect the input source to the selected analog input channel on the VibrationVIEW I/O unit
  5. Start playback on the input source (e.g. if using a DAT record, click the Play button)
  6. Click the "Start" button to start recording. When finished, click the "Stop" button
  7. Click the "Create Table" button to process the input and create the frequency/amplitude breakpoint table from the data. Note:The Random Import feature is an optional feature and requires the software key be programmed to enable it.For printable instructions, click here

How do I set up my profile to automatically generate a report when my test is complete?

To automatically generate a report, follow these simple steps

  1. Go to the test Settings and select the Schedule tab
  2. Next, Insert a row at the end of your test schedule
  3. In the pull-down section (where the default is generally %), select Save Report
  4. Next, select Browse, next to Save Report, to choose the report template you want VibrationVIEW to use when generating the report The Schedule tab should look something like this
  5. Now select the Data tab to define where the report will be saved. Use the Browse button to set up this location. The Data storage directory you set here will be location that Save data to disk data will be stored also, if you check any of the boxes (i.e. at end of test). Note: Graph annotation lines at the bottom of the Data tab can be filled in for each test with information such as test sample number, test technician, shaker serial number, etc. This information can automatically be included in the report

For printable instructions, click here.

How do I make a custom report template?

To quickly make a custom report template, follow these simple steps

  1. Click on the Report button to open the report template folder
  2. Right click on the template you would like to modify
  3. This opens the template in Rich Text Format. You can then edit the parameters you would like shown on your reports. For details on these parameters please see your manual, or in VibrationVIEW, go to Help..How To Create customized reports. There you will find a section for each mode of testing (sine, random, etc). The parameters found in the Help file can be copied and paste into your templates. Also, you can paste your company logo into this template. Note: Separate templates are used for each mode of testing

For printable instructions, click here.


What kind of shakers can I control with my Vibration Research controller?

Vibration Research systems will control all electro-dynamic and servo-hydraulic shakers.

Software Modules

VibrationVIEW Software Modules

How can I find out which software modules I have?

Select Help..About in VibrationVIEW.

Can I purchase additional software modules after my initial system purchase?

Yes, you may contact a member of the Vibration Research sales team or your Vibration Research sales representative at any time to enable additional software modules. Delivery is fast and easy - you will receive a link to download a key update file. Simply install this key update file and the new software module will be enabled.

Software Versions

VibrationVIEW Software Versions

How can I find out which VibrationVIEW software version I have?

Select Help..About in VibrationVIEW. The version number is also printed on the VibrationVIEW CD label.

What is the latest version of VibrationVIEW?

  1. VibrationVIEW 11.3.2 for the 9500 system
  2. VibrationVIEW 11.3.2 for the 8500 system
  3. 3.1.7 for the 7500 system

Where can I get the latest version of VibrationView?

If you purchased your vibration control system from Vibration Research in the last one (1) year, or have a current Upgrades & Support Agreement, then you are entitled to free software updates. If your system is more than one year old, call Vibration Research at (616) 669-3028 or email us.

Total Harmonic Distortion

What is Total Harmonic Distortion?

Did you ever see specifications on harmonic distortion, and wonder how to check out the measurements? You can buy harmonic distortion analyzers to do this for you, but there is another way, that of using the equipment you have right in your laboratory -- your random vibration controller/analyzer.

Harmonic distortion, or total harmonic distortion (THD) is the summation of the amplitudes of various harmonics when a pure sine tone is put into a system. The system is traditionally accepted to be the amplifier, such as your home stereo system.

However, there are many sources of harmonic distortion. The generator that generates the "pure" sine tone will generate harmonics. The system which you are exciting may be the source of the harmonic distortion. This might include the power amplifier and the shaker, which translates the electrical energy to mechanical energy. Lastly, the measuring equipment will have errors in it.

How can I measure the Total Harmonic Distortion of my shaker with my vibration controller?

You can measure this by exciting your system with a sine wave, and reading the g^2/Hz displayed by the system and noting the dB difference between the fundamental frequency (the one you are putting into the system) and any higher order harmonics. The harmonics will occur at 2x, 3x, 4x, etc. of the fundamental frequency. Since most controllers read directly in g^2/Hz, it is helpful to know that a change in 10x g^2/Hz is a 10dB change. For example, 0.1 g^2/Hz to 0.01 g^2/Hz represents a 10 dB change.
Remember that: dB=20 log (A/B).

Thus, a 10% distortion (0.1 ratio) will show up as -20 dB.
-20dB = 20 log (0.1)

Change in dB

Change in %

Change in dB

Change in %

Change in dB

Change in %

























































































































Here is an example showing harmonic distortion from a sine wave generator. The generator is set to 100 Hz. The third harmonic is the highest spike and is 40 dB ( 4 major divisions )down from the 100 Hz fundamental. This test reports the third harmonic distortion at 1%, which matches the specification for this waveform generator. Also, 40 dB correlates to 1% on the table.

Click the picture for larger view.



Where can I get additional training for my VibrationVIEW system?

See our VibrationVIEW User Training Program page.
Onsite training is also available. Call Vibration Research Corporation at (616) 669-3028 or email us at for a quote.

Warranties & Upgrades

What hardware warranty is available for my Vibration Research controller?

The VR9500 Revolution controller comes with a 3 year hardware warranty, which can be extended up to 6 years by continued (no lapse) renewal of your Upgrades & Support Agreement. Please contact Vibration Research or your sales representative for more information about this.

What Upgrades are available for my Vibration Research controller?

A one (1) year Upgrades & Support Agreement is provided with the purchase of a new vibration control system. After this period, you may continue to purchase annual Upgrades & Support Agreements by contacting your sales representative.


Innovators in Vibration Control
Experienced, industry leaders offering state-of-the-art vibration controllers for electrodynamic and servo-hydraulic shakers.