Rion VA-12 User manual

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Vibration Analyzer VA-12
Quick Instruction Manual
(Ver. 1.00）
RION CO., LTD.
Measuring Instruments Sales and Engineering Division,
Sound and Vibration Measuring Instruments Business Department
Contents
1. Fundamental operations
1.1 Operation key panel
1.2 Fundamental operations for preparation
2. Measurement in Vibration Meter Mode
3. Measurement in Time Waveform Mode
4. Measurement in FFT Analyzer Mode
5. Examples of typical vibration measurement
5.1 Diagnosis of unbalance and misalignment
5.2 Diagnosis of rolling element bearings
5.3 Measurement of natural frequency
6. Data store and recall
6.1 Store and recall operations of measurement data
6.2 Store and recall operations of screen bitmap image
6.3 Data transfer to a computer via USB
6.4 Data import to Microsoft Excel

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1. Fundamental operations
1.1 Operation key panel
1.2 Fundamental operations for preparation
VA-12 has three analysis functions: Vibration Meter Mode, Time Waveform Mode, and FFTAnalyzer Mode.
The operation about common setups to each analysis function before starting measurement is explained in this
section.
①Inserting the SD card
Insert the SD card into the card slot.
②Power on
Press the POWER key for a while (longer than 1 second).

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③Sensitivity setting of the accelerometer
◆PV-57I (Supplied accessory)
Usually it is not necessary to change the “Sensor Selection”since the default condition is set to PV-57I.
Press the MENU key, and go into the submenu [Analog Input] from the Menu List. Then check that “Sensor
Selection”is set to “PV-57I”. If it is set to “Other”, change it to “PV-57I”.
◆Other accelerometers than PV-57I (Optional accessory)
When the amplitude of vibration is too small or too large, or the frequency is too high, the PV-57I cannot
measure them. In that case an accelerometer suitable for the vibration characteristic should be chosen.
Press the MENU key, and go into the submenu [Analog Input] from the Menu List. Then change the
“Sensor Selection”to “Others”. Also set the “Sensitivity”to the sensitivity value given on the calibration
chart of the selected accelerometer.
Sensor selection（Other）
Sensor selection（PV-57I）

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④Setting the high-pass filter and low-pass filter
Set the “High-pass filter”and the “Low-pass filter”in the [Analog Input] submenu, according to the
measurement purpose. The followings are examples of setup for typical vibration measurements.
◆Setup for the unbalance or misalignment measurement
High-pass filter:10 Hz、Low-passfilter:1 kHz
◆Setup for the bearing defect measurement
High-pass filter:1 kHz、Low-passfilter:20 kHz
⑤Attaching the accelerometer
Attach the accelerometer to the measuring point of the object. Since an impulsive vibration occurs when
attaching the accelerometer, it is necessary to wait about 30 seconds until the influence of the impulsive
vibration disappears. Moreover, it is necessary to care about the contact resonance frequency of the
accelerometer which depends on the mounting method.
The desirable measuring points are as follows.
・A point near the measuring object.
・A rigid point.
・A flat and smooth point.
・A point without thick paint.
⑥Measurement by each analysis function
The explanations about common setups end here. Actual vibration measurement is performed by Vibration
meter mode, Time waveform mode, and FFT mode.
Refer to the subsequent pages of this manual for the details of the measurement procedure for each analysis
function.
Setting the Low pass filter Setting the High pass filter

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2. Measurement in Vibration Meter Mode
①Selecting the analysis function to “Vibration meter mode”after common setups.
Press the VM/TIME/FFT key to select the Vibration meter mode. The analysis function can be selected to each
mode as shown in the following figure by pressing the VM/TIME/FFT key.
The five kinds of vibration values are measured and displayed simultaneously and updated in one second
intervals. The bar graph indicates a selected data by the ACC/VEL/DIAP key. Acceleration, Velocity, and
Displacement are selectable.
②Input range setting
Set the input range to the optimal setting. The optimal setting is to use the lowest range where an overload
does not occur. The key changes to the higher range, the key changes to the lower range.
By changing input range, an electric transient noise occurs and overload may be displayed. In this case, it is
not an excessive input of vibration. When an overload is displayed immediately after changing input range,
please wait for a while. The overload may disappear.
Measurement data (Bar graph)
（ACC/VEL/DISP）
Vibration Meter Mode Time Waveform Mode FFT Mode
VM/TIME/FFT key
Acceleration rms
Acceleration peak
Acceleration crest factor
Velocity rms
Displacement equivalent P-P
ACC/VEL/DISP key

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When the overload occurs, the background color of display changes to red and the “Over”indication appears
to the upper right side.
③Reading the measured value
When the PAUSE/CONT key is pressed, the measurement
changes to the paused state, and a measured data is fixed
for reading the value. To resume the measurement,
press the PAUSE/CONT key one more time.
④Storing the measured data
Store the data if necessary. When the STORE key is pressed,
the data at that time is stored on SD card in VA-12.
When in a paused state, the fixed data is stored.
3. Measurement in Time Waveform Mode
①Selecting the analysis function to “Time waveform mode”after common setups
Press the VM/TIME/FFT key to select the Time waveform mode. The analysis function can be selected to
each mode as shown in the following figure by pressing the VM/TIME/FFT key.
PAUSE/CONT key STORE key
Vibration Meter Mode
Time Waveform Mode FFT Mode
VM/TIME/FFT key
RANGE key
Overload state

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②Selecting the measurement data type
Select the measurement data type by pressing the ACC/VEL/DISP key.
Acceleration, Velocity, Displacement, and Envelope are selectable.
③Input range setting
Set the input range to an optimal setting. The optimal setting is to use the lowest range where an overload does
not occur. The key changes to the higher range, the key changes to the lower range.
By changing input range, an electric transient noise occurs and overload may be displayed. In this case, it is
not an excessive input of vibration. When an overload is displayed immediately after changing input range,
please wait for a while. The overload may disappear.
When the overload occurs, the “Over”indication appears to the left side of display.
ACC/VEL/DISP/
ENVELOPE
Frequency span Number of analysis
lines
Upper limit time
ACC/VEL/DISP
key
RANGE key
Overload state
Overload indication

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④Setting the Frequency span and the Number of analysis lines
Set up the Frequency span and the number of analysis lines so that the measured time waveform can be
observed clearly by the FREQ SPAN key and the LINE key. The details of a time waveform can be observed
when the frequency span is set to high, but the maximum display time becomes short.
⑤Fixing a measured time waveform
When you read the amplitude of time waveform with cursor, press the PAUSE/CONT key. The measurement
changes to the paused state, and a measured time waveform is fixed.
To resume the measurement, press the PAUSE/CONT key one more time.
⑥Zooming the X-axis and the Y-axis of the graph display
When the SCALE ON/OFF key is pressed, the display scaling function becomes operational. In this case, the
graph zoom symbol or the cursor move symbol is shown at the bottom left corner of the display.
The graph zoom symbol and the cursor move symbol can be selected by the SCALE EXPAND/MOVE key.
FREQ SPAN
key
LINE
key
SCALE
ON/OFF
key
SCALE
EXPAND/MOVE key
Setting Frequency span Setting Number of
analysis lines
Select an item from a popup list
Cursor

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◆Cursor move symbol : Move mode
◆Graph zoom symbol : Zoom mode
The keys for zoom operation are as follows.
ExpandY-axis , ShrinkY-axis , Expand X-axis , Shrink X-axis .
Expansion of the X-axis is performed so that the present cursor position locates at the center.
⑦Storing the measured data
Store the data if necessary. When the STORE key is pressed,
the data at that time is stored on SD card in VA-12.
When in a paused state, the fixed data is stored.
4. Measurement in FFT Mode
①Selecting the analysis function to “FFT mode”after common setups
Press the VM/TIME/FFT key to select the FFT mode. The analysis function can be selected to each mode as
shown in the following figure by pressing the VM/TIME/FFT key.
Y
軸拡大縮小
X
軸拡大縮小
カーソル移動
STORE key
Vibration Meter Mode Time Waveform Mode FFT Mode
VM/TIME/FFT key
X
-
axis
expansion
Y
-
axis
expansion
Cursor move
PAUSE/CONT key

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②Setting the Window function
Press the MENU key, and go into the submenu [FFT] from the Menu List. Then select the “Window function”
to a suitable setting.
The window function is chosen as follows according to the measurement purpose.
◆Rectangular : It is used for the phenomena without repetition like a single pulse.
◆Hanning : It is used for the usual measurement.
◆Flattop : It is used for reading the amplitude correctly, although the frequency resolution may be worse.
③Selecting the measurement data type
Select the measurement data type by pressing the ACC/VEL/DISP key.
Acceleration, Velocity, Displacement, and Envelope are selectable.
Maximum frequency
ACC/VEL/DISP
key
Frequency span
Setting the Window function
ACC/VEL/DISP/
ENVELOPE
Number of analysis
lines

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④Input range setting
Set the input range to an optimal setting. The optimal setting is to use the lowest range where an overload does
not occur. The key changes to the higher range, the key changes to the lower range.
By changing input range, an electric transient noise occurs and overload may be displayed. In this case, it is
not an excessive input of vibration. When an overload is displayed immediately after changing input range,
please wait for a while. The overload may disappear.
When the overload occurs, the “Over”indication appears to the left side of display.
⑤Setting the Frequency span and the Number of analysis lines
In order to determine the maximum frequency to analyze and the frequency resolution, the frequency span and
the number of analysis lines are set up. The frequency span can be selected by the FREQ SPAN key, and the
number of analysis lines can be selected by the LINE key.
Set the frequency span about three times larger than the fundamental frequency if the frequency can be
predicted like a rotating machine. Also set the number of analysis lines so that the frequency resolution
becomes narrower than 1 Hz. The frequency resolution is obtained by the frequency span divided by the
Overload state
RANGE key
Overload indication
FREQ SPAN
key
LINE
key
Setting the Frequency span Setting the Number of
analysis lines
Select an item from a popup list

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number of analysis lines. If the generated frequency cannot be predicted, measure the frequency roughly with
high frequency span at first, then set the frequency span and the number of analysis lines so that the
frequency resolution becomes narrower than 1 Hz.
⑥Setting the Operation type
In the Instantaneous measurement, it is not necessary to set the operation type. In the measurement with
operation function, it is necessary to select the operation type. Then press the INST/AVE key, and press the
START/STOP key.
In order to select the operation type, presses the MENU key, then go into the submenu [FFT] from the Menu
List, and set the Operation type and the Average number.
◆Instantaneous measurement
FFT spectra are continuously displayed without averaging. It is used when grasping the characteristics of
phenomenon by observing the time variation of the spectrum, or when the average is not necessary since
the vibration is steady.
The operation type is chosen as follows according to the measurement purpose.
◆Linear average
It is a popular averaging type, and is used to obtain the arithmetic averaged result. The operation stops
when the number of measured data reaches to the Average number set in the submenu [FFT].
◆Exponential average
FFT spectra are continuously displayed with a time constant. When amplitude of vibration changes
violently, the averaged amplitude becomes smooth. It is used when grasping the characteristics of
phenomenon by observing the time variation of the spectrum. If an impulsive vibration occurs, you may
miss it in Instantaneous measurement. However you will not miss it in exponential average, since the time
constant keeps the influence of the impulsive vibration for a while.
◆Maximum hold
It is used when obtaining the maximum value of each frequency component. The operation stops when the
number of measured data reaches to the Average number set in the submenu [FFT].
Setting the Operation type Setting the Average number

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In order to start the operation function, press the INST/AVE key. In that case, an operation type is displayed at
the upper left part of display. In Linear average, [LIN] is shown, in Exponential average, [EXP] is shown, and
in Maximum hold, [MAX] is shown. The average number is also displayed. If the INST/AVE key is pressed
again, it will change to the Instantaneous measurement and [INST] is shown.
If the START/STOP key is pressed where the operation type is LIN, EXP, or MAX, the average will start and
the counter of the average number will go up. If the START/STOP key is pressed again during the average
operation, the average will stop at the time. If the START/STOP key is pressed in the Instantaneous
measurement, the average will not start.
⑦Fixing a FFT spectrum
In Linear average or Maximum hold, the operation stops when the average counter reaches to the average
number, and the FFT spectrum is fixed.
In Instantaneous measurement or Exponential average, the operation continues. When you read the frequency
or the amplitude of spectrum with cursor, press the PAUSE/CONT key. The measurement changes to the
paused state, and a measured FFT spectrum is fixed. To resume the measurement state, press the
PAUSE/CONT key one more time.
⑧Zooming the X-axis and the Y-axis of the graph display
When the SCALE ON/OFF key is pressed, the display scaling function becomes operational. In this case, the
graph zoom symbol or the cursor move symbol is shown at the bottom left corner of the display.
The graph zoom symbol and the cursor move symbol can be changed by the SCALE EXPAND/MOVE key.
Instantaneous
measurement
Operation type
LIN/EXP/MAX
A
verage number
START/STOP key
INST/AVE key
Instantaneous value state Averaged state

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◆Cursor move symbol : Move mode
◆Graph zoom symbol : Zoom mode
The keys for zoom operation are as follows.
Expand Y-axis , Shrink Y-axis , Expand X-axis , Shrink X-axis .
Expansion of the X axis is performed so that the present cursor position locates at the center.
The example of operation to expand the X-axis is as follows. It is assumed that the cursor move symbol is
displayed at first. If the Graph zoom symbol is displayed at first, press the SCALE EXPAND/MOVE key to
change the zoom mode.
Move the cursor to the position where you want to expand. Press the SCALE EXPAND/MOVE key, then
Cursor move symbol is displayed. Press the key. The X-axis is expanded twice on the basis of the
cursor position. When you press the key once, the X-axis is expanded twice.
SCALE
ON/OFF
key
SCALE
EXPAND/MOVE key
Y
軸拡大縮小
X
軸拡大縮小
カーソル移動
X
-
axis
expansion
Y
-
axis
expansion
Cursor move

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Press the key
⑨Storing the measured data
Store the data if necessary. When the STORE key is pressed,
the data at that time is stored on SD card in VA-12.
When in a paused state, the fixed data is stored.
STORE keyPAUSE/CONT key
Original graph Move the cursor to the position
you want to expand
E
xpand
×
4
E
xpand
×
8
E
xpand
×
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Cursor
Cursor SCALE
EXPAND/MOVE key
Press the SCALE EXPAND/MOVE
key
Graph zoom symbol is displayed
The X-axis is expanded twice on
the basis of the cursor position

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5. Examples of typical vibration measurement
The followings are the examples of VA-12 settings for some typical vibration measurements. The minimum settings
for the measurement are described. The input range should be set up according to the amplitude of vibration so that
an overload may not occur.
5.1 Diagnosis of unbalance and misalignment
The vibration velocity is measured to diagnose the structural defects like unbalance or misalignment. The
measurements in three directions (horizontal, vertical, and axial) are necessary to diagnosis. And the biggest
value in them is used for diagnosis.
In survey diagnosis, the root mean square values of the vibration velocity are measured by Vibration Meter Mode.
If the measured value exceeds the criterion and the judgment is abnormal, the precise diagnosis is carried out. In
this case, the defect part and the cause are investigated by Time Waveform Mode or FFT Analyzer Mode. In
unbalance condition, only a shaft rotational frequency appears, but in misalignment condition, a shaft rotational
frequency and its harmonics appear. Since the vibration velocity relates to the vibration severity which indicates
the violence of total vibration, if the vibration velocity increases, there may be some abnormalities.
Fundamental settings
High-pass filter：10 Hz
Low-pass filter：1 kHz
◆Survey diagnosis
Analysis function：Vibration Meter Mode
Measurement data type：Velocity
◆Precise diagnosis by time waveform
Analysis function：Time Waveform Mode
Measurement data type：Velocity
Frequency span, Number of analysis lines：Set up so that the time waveform can be observed
◆Precise diagnosis by FFT analysis
Analysis function：FFTAnalyzer Mode
Measurement data type：Velocity
Window function：Hanning window
Frequency span：200Hz (unbalance)、200Hz or 500Hz (Misalignment)
Number of analysis lines：Set up so that the frequency resolution becomes narrower than 1Hz
Operation type：It is used if necessary

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An example of misalignment：The shaft rotational frequency (20.25Hz), the third harmonics (60.75Hz) and the
6th harmonics (121.5Hz) can be observed.
5.2 Diagnosis of rolling element bearings
Since the acceleration increases if a bearing defect becomes large, vibration acceleration is measured to diagnose
bearings. Attach the accelerometer to the bearing as near as possible. The measurement direction is available in
any directions among horizontal, vertical, and axial direction.
In survey diagnosis, the root mean square values and the crest factor of the vibration acceleration are measured
by Vibration Meter Mode. If the vibration acceleration exceeds the criterion and the judgment is abnormal, the
precise diagnosis is carried out. In precise diagnosis, the defected part can be predicted by FFT analysis of
acceleration envelope, if the information about the bearing to diagnosis is known, for examples, rotating speed,
diameter of ball, number of balls, pitch diameter, and contact angle.
Fundamental settings
High-pass filter：1 kHz
Low-pass filter：20 kHz
◆Survey diagnosis
Analysis function：Vibration Meter Mode
Measurement data type：Acceleration rms value and Acceleration crest factor
◆Precise diagnosis by time waveform
Analysis function：Time Waveform Mode
Measurement data type：Acceleration and Envelope
Frequency span, Number of analysis lines：Set up so that the time waveform can be observed
◆Precise diagnosis by FFT analysis
Analysis function：FFTAnalyzer Mode
Measurement data type：Acceleration and Envelope
Time waveform (velocity) FFT (velocity)

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Window function：Hanning window
Frequency span：20kHz (Acceleration),200Hz or 500Hz (Envelope)
Number of analysis lines：Set up so that the frequency resolution becomes narrower than 1Hz
Operation type：It is used if necessary
An example of outer race defect of a bearing：The Ball Pass Frequency of Outer race can be observed at 77.8Hz.
5.3 Measurement of natural frequency
The natural frequencies of a structure can be measured by exciting the object. Attach an accelerometer to the
object, and excite it with an impulse hammer. In measurement, it is necessary to use the trigger function and the
linear average. Refer to the instruction manual of VA-12 about the details of the trigger function. When an
exciting point and an attached point of the accelerometer changes to the other position, the measured frequencies
may change. In this case, all the measured frequencies are considered as natural frequencies.
Fundamental settings
Sensor selection：PV-57I (in usual case),
A lighter accelerometer for example PV-91C (when the object is very small and light)
High-pass filter：10 Hz
Low-pass filter：20 kHz
Analysis function：FFTAnalyzer Mode
Measurement data type：Acceleration
Window function：Rectangular window
Frequency span：5 kHz（Set up so that the whole natural frequencies are included）
Number of analysis lines：3200（Set up so that the whole decay process of a time waveform can be
observed）
Operation type：Linear average、Average number：about 5
FFT (envelope)
Time waveform (acceleration)

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FFT Scale：Log (The display range becomes wide when the FFT scale is set to Log. It is often used in
impact excitation measurement.)
Trigger operation mode：Repeat
Trigger source：Level
Pre-trigger：ON
Trigger level：1/8 ～2/8
Slope：＋
The trigger conditions are set in the submenu [Measurement]. Press the MENU key, and go into the submenu
[Measurement] from the Menu List.
A measurement example of natural frequencies of a stainless plate (200mm×100mm×20mm)：
The 2.54 kHz and the 2.89 kHz are natural frequencies.
Setting the trigger conditions
FFT (acceleration)
Time waveform (acceleration)

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6. Data store and recall
6.1 Store and recall operations of measurement data
①Setting the Store Name
Press the MENU key, and go into the submenu [Measurement] from the Menu List. Then set the “Store Name”.
Specify the number which follows MAN_ like “0001”to any value.
Up to 1000 data can be stored in one “Store Name”.
②Selecting store address and data storing
The store address is indicated at the upper right corner of display. This store address means the address
contained in a “Store Name”which was set up at the previous step. The measured data can be stored in the
indicated store address by pressing the STORE key. The store address can be selected by keys.
When the data already exists in the selected address, the background color of the address is displayed to red.
Data will be overwritten if the STORE key is pressed in this state.
STORE key
Select a store address
Store address Stored data already exists
Setting the store name