When set the acceleration to A (m/s²), speed to B (m/s), displacement to C (m) and frequency to f (Hz), the following formula is satisfied.

 

 

As you can see from the above formula, if you do not know the frequency, you cannot convert the vibration level data into displacement. It is necessary to obtain the frequency by using the VR-0654 Real-time octave analysis function (option) etc.

 

The acceleration value is effective value for the vibration level meter. If the vibration acceleration A (m/s²) is rms (rms: effective value), and the 0 dB value is 10^-5 (m/s²), the vibration level D (dB) can be obtained by the following formula.

 

 

When the vibration acceleration A is 1 (m/s²) rms, the vibration level D is 100 (dB).

 

The example of conversion into the displacement

 

When the vibration level which is obtained by the Z axis 1/3 octave analysis of the VR-6100 is 35 dB/10 Hz, the calculation procedure is as follows.

Obtain the vibration acceleration by the above formula (3);

 

 

Then, convert into displacement by the above formula (2).

 

 

The vibration level 35 dB/10 Hz is an effective value of 0.143 µm in the vibration displacement.

 

In addition, the overall value of the displacement is the square average value of the displacement of each frequency. For example, when set the displacement value of each 1/3 octave frequency as D1, D2, D3… Dn, the overall value (OA) can be obtained in the following formula;