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Reference Information
Peak Vector Sum (PVS)
The VM-56 calculates the PVS by triaxial synthesis (sum of squares) of the PPV for
each axis measured every 100 ms.
The PVS determined by computation is stored as the maximum value of PVS every
100 ms.
The calculation formula and a schematic diagram of the PPV waveforms (in the
order X axis, Y axis, and Z axis) are shown below.
X_PPV : Peak particle velocity of X axis
Y_PPV : Peak particle velocity of Y axis
Z_PPV : Peak particle velocity of Z axis
100
ms
1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0
-0.2
X_PPV
PPV [mm/s]
1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0
-0.2
Y_PPV
100
ms
PPV [mm/s]
1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0
-0.2
PPV [mm/s]
Z_PPV
100
ms
√PVS = X_PPV
2
+ Y_PPV
2
+ Z_PPV
2