MMF VM100 User manual

Instruction Manual
Manfred Weber
Metra Mess- und Frequenztechnik in Radebeul e.K.
Meissner Str. 58 - D- 1445 Radebeul
Tel. [phone] Fax [phone]
Email: [email protected] Internet: www.MMF.de
Vibration
Analyzer
VM100
Valid from Version 1. 1

Published by:
Manfred Weber
Metra Mess- und Frequenztechnik in Radebeul e.K.
Meißner Str. 58
D-0 445 Radebeul
Tel. [phone]
Fax [phone]
Email [e-mail]
Internet www.MMF.de
Note: The latest version of this manual can be found at:
http://www.mmf.de/product_literature.htm
Specifications subject to change.
© 2022 Manfred Weber Metra Mess- und Frequenztechnik in Radebeul e.K.
Full or partial reproduction subject to prior written approval.
Apr/ 23

Contents
. Purpose.................................................................................................................3
2. Properties..............................................................................................................3
3. Operation..............................................................................................................4
3. . Connectors and Controls...............................................................................4
3.2. Switching On / Off and Reset........................................................................5
3.3. Menu Bar......................................................................................................5
3.4. Sensors..........................................................................................................6
3.5. USB Connection...........................................................................................7
3.6. Charging the Accumulator............................................................................7
3.7. SD Card and File System..............................................................................8
4. Measurement Modules..........................................................................................9
4. . Licenses........................................................................................................9
4.2. Module Amplitude/Time............................................................................. 0
4.3. Module Frequency Analysis (FFT)............................................................. 4
4.4. Module Amplitude/Rotation Speed.............................................................2
4.5. Module Machine Vibration.........................................................................24
4.5. . Introduction.........................................................................................24
4.5.2. Measurement Routes............................................................................25
4.5.3. Creating Measurement Points in a Route.............................................26
4.5.4. Trend Monitoring of Vibration Severity..............................................29
4.5.5. Roller Bearing Monitoring Using Overall Values................................32
4.6. Module Envelope Analysis.........................................................................34
4.6. . Introduction.........................................................................................34
4.6.2. Measurement........................................................................................34
4.7. Module Balancing.......................................................................................39
4.7. . Introduction.........................................................................................39
4.7.2. Measurement........................................................................................4
4.8. Module Third Octave Analysis (VC and Nano Criteria).............................56
4.8. . Introduction.........................................................................................56
4.8.2. Sensors for VC and Nano Criteria........................................................58
4.8.3. Measurement........................................................................................59
4.9. Module Hand-Arm Vibration......................................................................63
4.9. . Introduction.........................................................................................63
4.9.2. Hand-Arm Sensors...............................................................................66
4.9.3. Measurement........................................................................................67
4. 0. Module Whole-Body Vibration................................................................70
4. 0. . Introduction.......................................................................................70
4. 0.2. Whole-Body Sensors.........................................................................72
4. 0.3. Measurement......................................................................................76
4. . Module Whole-Body – 3 Sensors.............................................................80
4. . . Introduction.......................................................................................80
4. .2. Whole-Body Sensors.........................................................................80
4. .3. Measurement......................................................................................8
5. Saving Measurements and NFC Function...........................................................84
5. . Folders and File Names...............................................................................84
5.2. NFC Identification of Measuring Points.....................................................85
5.3. Saving Bitmap Screenshots.........................................................................86
5.4. Saving Data in CSV Format........................................................................87

5.5. Viewing Saved Measurement Data.............................................................87
5.6. Recording Raw Data in WAV Format.........................................................87
6. Presets.................................................................................................................90
7. Other Settings.....................................................................................................9
7. . Display Settings..........................................................................................9
7.2. Date and Time.............................................................................................92
7.3. Language.....................................................................................................92
7.4. Beep Signal.................................................................................................92
7.5. Factory Reset..............................................................................................92
7.6. Device Data.................................................................................................92
8. Firmware Update................................................................................................93
9. Technical Data....................................................................................................96
Appendix: Warranty
CE Declaration of Conformity
2

Thank you for choosing a vibration meter from Metra.
1. Purpose
The VM 00 vibration analyzer is suitable for many tasks of vibration measurement
tasks, such as:
•General measurements of overall values in time domain with recording
•Frequency analysis (FFT)
•Amplitude/RPM measurement
•Machine vibration monitoring
•Roller bearing analysis
•Balancing
•Third-octave analysis of extremely low vibration using “VC” and “Nano” criteria
•Hand-arm vibration to ISO 5349 with one or two hands
•Whole-body vibration (triaxial) to ISO 263 with health and comfort evaluation,
vibration on passenger and merchant ships to ISO 6954
•Whole-body vibration with three triaxial sensors for the evaluation of passenger
comfort in vehicles
2. Properties
The VM 00 can measure on up to nine channels simultaneously. It works with all
commercially available IEPE accelerometers. TEDS sensors are recognized. In addi-
tion, a photoelectric reflex switch can be connected for speed measurement.
The instrument is available in two versions:
•VM 00A with 9 inputs and internal infrared temperature sensor
•VM 00B with 3 inputs
The instrument is fully touch-operated making it simple and intuitive. The remov-
able micro SD card serves for storing measured values. A USB interface is used for
data transfer. Measurement data is stored in CSV format. This allows common
spreadsheet programs to be used for further processing on a PC.
3

3. Operation
3.1. Connectors and Controls
On the upper side of the case you will find a small keypad with the power button,
the reset button and a function key. The VM 00A also has an infrared temperature
sensor here. (Figures and 2). The charge LED lights up red when connected to a
USB charger or PC.
The USB port (Type C) for charging and transferring
data as well as the micro-SD card are also located behind
a flap on the upper side.
On the lower side you will find three sensor sockets for
the VM 00A and one for the VM 00B. Each of the four-
pole sensor sockets is suitable for connecting a triaxial
sensor (X/Y/Z). Figure 3 shows a view of the connectors
from outside. The assignment is:
: Ground
2: Channel X
3: Channel Y
4: Channel Z
The VM 00 has standard IEPE inputs.
A triaxial sensor requires three inputs. All triaxial accelerometers from Metra can
be connected via their standard cables.
Alternatively three single-axis sensors can be connected to each input socket. Metra
offers for this purpose an optional adapter cable with three female BNC connectors.
Here you will find also the tacho input (Figure 4) for a photoelectric reflex switch as
RPM sensor which has the following assignment:
: +26 V
2: Digital input D
3: Digital input D2
4: +5 V
5: Analog input A
5: Analog input A2
7: Ground
The inputs D2, A and A2 are currently not used.
4
Figure : Keypad of VM 00A Figure 2: Keypad of VM 00B
1
2 3
4
Figure 3: Sensor input
1
2
4
35
6
7
Figure 4: Tacho input

Behind a cover is another USB port, which is only for firmware updates.
3.2. Switchin On / Off and Reset
The VM 00 is switched on by briefly pressing the red key on the side keypad (Fig-
ures and 2). It always starts with the last selected settings and is immediately
ready for use in measuring mode. If the battery is completely discharged, it may be
necessary to connect a charger to start it.
To switch off, touch the on/off symbol at the top left of the screen.
When a battery charger or USB cable is connected the unit is started by a screen
button.
Should the instrument not start normally, you may perform a factory reset by hold-
ing the F button and pressing shortly RESET or by holding F while pressing .
The unit can be restarted from any program point by pressing the Reset key. Any
entries made previously are retained.
3.3. Menu Bar
All function modules use a uniform menu bar at the top of the screen (Figure5).
The menu bar contains the following components:
•Off button
•Function menu: Touch the menu text to open a drop-down menu with all func-
tion modules. Unlicensed functions are grayed out. Touching a menu item selects
the function. If no selection is made, the menu closes again after a few seconds.
•The info button provides a short help text to each measuring module.
•The menu button opens a menu structure with various settings and for USB
data transfer (see section 7).
•The save button opens the menu for saving data to SD card (Section 5). If no
SD card is inserted, the symbol appears crossed out.
•The menu bar shows the date and time. In the VM 00A, you can see the mea-
sured temperature of the built-in infrared sensor below it (Figure ).
•The battery indicator shows the current charge status of the unit. In case
of advanced discharge, the display bar turns yellow and in case of critical charge
state, it turns red. When the charger is connected, the charging symbol is
displayed alternating with the actual charge current. After charging is complete, a
plug symbol for battery support appears on the right (see section 3.6).
5
Figure 5: Menu bar

3.4. Sensors
The sensor menu (Figure 6) opens by selecting the Sensors item in the main menu.
It shows the sensitivities of the connected sensors. As in the entire user interface of
the VM 00, three input channels (X/Y/Z) are displayed for each input socket (" " to
"3" for VM 00A or " " for VM 00B). For inputs without a sensor, "No sensor" ap-
pears.
The VM 00 supports TEDS sensors. TEDS stands for "Transducer Electronic Data
Sheet" and is standardized according to IEEE 45 .4. The most important technical
data is stored digitally in the sensor and can be read out automatically by the mea-
suring instrument. Measurement errors due to confusion or incorrect entries are thus
eliminated. The standard data arrangement for accelerometers according to "Tem-
plate 25" is supported. If a TEDS transducer is detected, the sensor menu shows its
sensitivity, type designation and serial number. In Figure 6 this is shown for a
TEDS triaxial sensor at socket . The sensitivity of TEDS sensors cannot be edited
in the menu.
For conventional IEPE sensors, touching the sensitivity opens a numeric input pad
for entering the sensitivity. The unit of measurement can be changed to mV/Pa for
pressure transducers and measuring microphones or mV/N for force transducers.
The units of measurement Pascal or Newton are then displayed instead of accelera-
tion in some operating modes.
The speed sensor can be deactivated if it is not required. It then no longer appears in
the measured value display. With the button sensor detection can be repeated.
6
Figure 6: Sensor menu

3.5. USB Connection
On the upper side, you will find the USB port behind a flap (Figure 0). It is a USB-
C connector. It is used to charge the battery and transfer data. To transfer the files
stored on the SD card, connect the VM 00 to a PC via a USB cable. To activate
data transfer, select USB connection in the main menu (Figure 7). You will then see
the display corresponding to Figure 7.
The VM 00 is now in USB mass storage mode. It does not need a device driver and
behaves like a USB stick by providing the file system of the SD card.
For sensitive measurements, the USB cable should be disconnected.
3.6. Char in the Accumulator
The built-in nickel-metal hydride rechargeable battery is
charged via the USB-C socket (Figure 0). A USB mains
adapter is used for charging, which should deliver at
least 3 A from 5 V. Otherwise, the full charging current
may not be provided and the charge time is extended.
If a USB supply is connected, the red charging LED
lights up (Figures and 2).
If the USB supply is connected when the VM 00 is
switched off, the charge screen opens (Figure 9). It will
be dimmed after a short time. You can check whether the
device is still charging by touching the screen.
When switched on, the status bar on the top right shows
the charging symbol alternating with the actual
charge current flowing into the battery. Depending on
the connected USB interface or charger the input current
may be in the range from 0.5 to 2.5 A. About 0.7 A of this current are needed for
the instrument itself. Standard USB 2.0 sockets provide only 0.5 A which means
that there may be no current left for charging the battery and instead it may be fur -
ther discharged.
When charging is complete, the battery and plug icon appears .
At advanced discharge, the indicator bar turns yellow and in case of critical charge
state, it turns red.
Reducing the display brightness (see section 7. ) may considerably increase the
battery operating time.
7
Figure 7: Main menu
Figure 8: USB connection
Figure 9: Charge screen

For sensitive measurements, the charger should be disconnected.
3.7. SD Card and File System
The SD card serves as a measurement data memory. It is located behind the flap
next to the USB socket (Figure 0). The VM 00 uses the FAT file system. The
files can be transferred to a PC via a USB cable as shown in section 3.5. If neces-
sary, the SD card can be removed after unlocking it by pressing slightly on its edge.
You can read out the data in other devices. Insert the SD card into the VM 00 with
the contacts facing up. It is recommended only to use memory cards of size 2 GB.
For more details on measured value storage, refer to section 5.
➔It is strongly recommended to make regular backups of the data stored on the
SD card.
➔Saving additional files to the SD card or creating additional folders using other
devices is not advisable.
8
Figure 0: Charge connector and SD card slot

4. Measurement Modules
4.1. Licenses
The VM 00 supports a number of tasks, which are divided into measurement mod-
ules. Figure shows the menu with all available modules.
Amplitude/Time and Frequency Analysis are pre-installed by default. The other
functions can be activated by purchasing license codes. This is done by a text file
with the name VM 00 #xxxxxx licence.key, which has to be saved in the main di-
rectory of the SD card. Here x...x stands for the 6-digit serial number of the device
according to the type label or device data menu (see section 7.6). You receive this
license file from the manufacturer. It is only required for entering the licenses once.
The licenses are read automatically after the device is switched on. Later the license
file is not needed anymore but it can be left on the SD card. A note will be dis-
played for each newly added license.
9
Figure : Measurement modules

4.2. Module Amplitude/Time
This module is pre-installed by default and is suitable for overall value measure-
ments in time domain. In the upper part there is the unified menu bar, which is de-
scribed in section 3.3. On the left, up to nine vibration values are displayed. On the
right, the measurements are displayed graphically as a time graph (Figure 2).
In addition you can measure and plot rotation speed (rpm). Prerequisite for rotation
speed measurement is the connection of a photoelectric reflex switch VM 00-LS
(see Figure 52 on page 4 ).
The writing of the amplitude graphs starts 5 s after the start of the module in order
to suppress transients. The waiting time can be skipped by touching the respective
message in the diagram.
For sensitive measurements, the USB cable should be disconnected.
Touching one of the channel buttons on the left edge opens the menu for setting the
measuring channel (Figure 3).
Alternatively, you can apply the same settings to all channels by touching the lowest
button “ALL” (Figure 4). In this mode you can also choose between the units
/min and Hz for rotation speed.
0
Figure 2: Display in the module Amplitude/Time

The display channels to 9 can be connected freely with any of the physical sensor
inputs X, Y and Z for model VM 00B and with sensor inputs X to 3Y for
model VM 00A.
The selection in the Sensor menu connects the display channel with a physical sen-
sor input. Even with the three-channel VM 00B, up to nine measured values can
thus be displayed. For example, different overall values or frequency bands can be
displayed for one sensor.
The value to be displayed is selected under Mode. The following overall values can
be measured:
RMS Root-mean-square value with s averaging time
RMS(T) Root-mean-square value with unlimited averaging time
Peak Peak value (0 – Peak) with s hold time
Pk-Pk Peak-to-peak value with s hold time
Pk hold Maximum peak value (0 – Peak) with unlimited hold time
Crest Crest factor (Peak/RMS)
Figure 3: Settings for one channel
Figure 4: Settings for all channels simultaneously

Frequ. Main frequency (frequency of highest FFT amplitude), only
with 4 kHz bandwidth and for 3 channels max.
Vector Square root of the sum of squares (vibration total value) of dis-
play channels , 2 and 3; only selectable at channels 8 and 9*
Vector 2 Square root of the sum of squares (vibration total value) of dis-
play channels 4, 5 and 6; only selectable at channels 8 and 9*
* The vector values are calculated by adding the squared amplitudes of the re-
spective display channels without consideration of same mode, filters etc.
In the Integration menu, you can select whether no integration, single integration
or double integration is to be performed. Integration is only useful in connection
with accelerometers. Single integration provides the vibration velocity, double inte-
gration the vibration displacement.
Furthermore, high pass filters between 0.2 and 5000 Hz and low pass filters be-
tween 0 and 24 000 Hz can be selected. The following restrictions apply:
•The highest selectable high-pass frequency is one third of the low-pass fre-
quency.
•The maximum frequency range for single integration is from 2 to 2000 Hz.
•The maximum frequency range for double integration extends from 2 to 300 Hz.
•Low pass filters above 4000 Hz can only be used for three-channel measure-
ments with fixed channel/sensor assignment. Frequencies above 4000 Hz can
only be selected on the upper three display channels. The high pass frequencies
2, 3 and 4 Hz are not available in this case. Main frequency and s quare root of
the sum of squares are not available.
The high and low passes are second order Butterworth filters with an attenuation of
40 dB per frequency decade. The low passes 4 kHz and 24 kHz are an exception.
For these, the very steep digital filter of the analog-to-digital converter becomes ef -
fective. The attenuation is already over 00 dB at .5 times the cutoff frequency. In
Figure 5 you can see the amplitude frequency responses with some filters as well
as integrators, related to the measurand acceleration of the sensor.
2

In the Gain menu, you can choose between automatic gain setting and the fixed
gains , 0 and 00. For most applications the "Auto" setting is recommended. Only
for strongly fluctuating amplitudes a fixed gain can be useful, in order to avoid con -
tinuous switching.
Plot selects whether the channel is displayed in the time diagram. Each channel has
an individual color which is used for the measured value and the time graph. If a
channel is not displayed in the time graph, its measured value appears in white.
All settings are retained even after the device is switched off or the measuring mod-
ule is changed.
In the time diagram, a data point is generated for each measured value. The diagram
is drawn starting from the left. On the left edge there is always the current recording
time. Towards the right, the measured data becomes older. The visible diagram area
covers 0 minutes. With the scroll bar you can browse the entire recording time of
up to 0 hours. After 0 hours, the oldest measurement data are shifted out of the
memory.
The Y-axis is logarithmically scaled. The units of measurement correspond to those
of the measured values.
In addition, rotational speed is displayed if this is activated in the sensor menu
(Section 3.4).
Diagram plotting can be halted (II) or restarted (I◄).
The storage of measured values takes place independently of the diagram as a CSV
data table. To do this, open the storage menu with and select CSV storage (see
section 5). The storage button then appears in yellow with the text "LOG". The
measured values are now written to a file every second. The file name and the num-
ber of measured values are displayed at the top of the diagram. To end the record-
ing, touch the save button again. The saved files can be found on the SD card in the
"AMP-TIME" directory.
3
0,1 1 10 100 1000 10000 100000
0,001
0,01
0,1
1
10
100
1000
10000 a: 10-1000 Hz
a: 100-10000 Hz
a: 0,2-4000 Hz
a: 1000-24000 Hz
v: 2-2000 Hz
v: 10-200 Hz
d: 2-300 Hz
d: 5-300 Hz
Hz
Figure 5: Frequency response of selected filters and integrators

Figure 6 shows an example of a CSV recording. In the header you will find infor-
mation about the measuring device and the sensors used. The table starts with the
channel settings, such as filters, overall values and measurement units. From line 20
start the recorded measured values of 9 channels and rotation speed with time
stamp. For channels without sensor, "IEPE!" is saved instead of measured values.
To stop recording press the button again.
After 24 hours a CSV log file is closed. A new file is opened automatically. It gets
the same file name with the appendix “..._a.csv”, the next file “..._b.csv” until
recording stops after 27 days with file “..._z.csv”.
Alternatively, the diagram can be saved as BMP screenshot.
For more details on measured value storage, see section 5.
4.3. Module Frequency Analysis (FFT)
This module is pre-installed by default. It performs a Fourier transform (FFT) and is
used to display the spectral composition of the acceleration signal of the three chan-
nels of sensor input . In the upper part there is the unified menu bar described in
section 3.3.
4
AMPLITUDE/TIME
Instr.: VM100A Ser.: 123456
Comment: TEST 2
N C Id:
Sensor 1X: Ser.: 170345 Sensit.: 10.313 mV/m/s²
Sensor 1Y: Ser.: 170345 Sensit.: 10.354 mV/m/s²
Sensor 1Z: Ser.: 170345 Sensit.: 10.879 mV/m/s²
Sensor 2X: Ser.: 181653 Sensit.: 100.45 mV/m/s²
Sensor 2Y: Ser.: 181653 Sensit.: 100.35 mV/m/s²
Sensor 2Z: Ser.: 181653 Sensit.: 100.18 mV/m/s²
Sensor 3X: Ser.: 173871 Sensit.: 10.313 mV/m/s²
Sensor 3Y: Ser.: 173871 Sensit.: 10.354 mV/m/s²
Sensor 3Z: Ser.: 173871 Sensit.: 10.879 mV/m/s²
Date: 20.01.2022 Temp.: 22 °C
Sensor: 1X 1Y 1Z 2X 2Y 2Z 3X 3Y 3Z RPM
HP (Hz): 5 5 1000 5 5 5 5 5 5
LP (Hz): 1000 1000 4000 4000 4000 4000 4000 4000 4000
Mode: RMS RMS RMS RMS RMS RMS RMS RMS RMS
Unit: m/s² m/s² m/s² m/s² m/s² m/s² mm/s mm/s mm/s rpm
11:36:38 0.962 0.963 0.600 1.275 1.275 1.216 1.016 0.936 0.924 0
11:36:39 0.963 0.923 0.601 1.275 1.187 1.216 1.009 0.936 0.924 0
11:36:40 0.777 0.726 0.578 1.103 1.043 1.061 1.025 0.921 0.928 0
11:36:41 0.775 0.733 0.575 1.103 1.040 1.062 1.029 0.930 0.940 0
11:36:42 0.779 0.730 0.575 1.088 1.048 1.049 1.018 0.921 0.939 0
11:36:43 0.769 0.735 0.580 1.100 1.035 1.062 1.013 0.921 0.933 0
11:36:44 0.770 0.735 0.578 1.097 1.048 1.062 1.019 0.925 0.937 0
Figure 6: Example of a CSV recording

The frequency range extends up to 22 kHz.
The entire screen width of 800 points is used to display the spectrum. At the bottom
right, you will see two buttons for zooming in and out of the visible frequency
range. In the selected frequency range you can navigate with the scroll bar. An ex-
ception is the lowest zoom level, in which the entire frequency range is displayed on
a width of only 460 points.
The scaling of amplitude and frequency axis is done with the plus/minus keys. Al-
ternatively, you may place two fingers on the screen and pinch in or stretch out ver-
tically or horizontally.
To the right or above the diagram, the largest spectral components of the three chan -
nels are displayed with frequency and amplitude. In addition, you can see there the
number of points with which the FFT is calculated. Depending on the zoom level, it
can be between 024 and 32786 which is about 2.2 times the shown number of
points. This results in a certain frequency step size per point, which is also shown.
In addition, there are window function, averaging and trigger mode.
The yellow measurement cursor is shifted with the wider lower end. In addition,
there are yellow arrow keys on the left and right for moving the cursor in single
steps. In the upper area of the cursor the three amplitudes and the frequency at the
selected cursor position are shown.
All graphic and numerical value outputs are in the characteristic color of the respec-
tive measuring channel.
The higher the number of points, the longer the calculation takes.
FFT calculation can be paused and continued with the buttons II and ►.
The button opens the FFT menu (Figure 8).
5
Figure 7: Measurement screen of frequency analysis

The scaling of the amplitude axis can be switched between linear and logarithmic.
Windowing determines with which weighting the obtained sample values within a
section (window) are used in subsequent calculations. Due to the block-wise pro-
cessing of the signal, so-called leakage effects occur on the edges of a block, which
make the spectral components appear too wide. This effect can be reduced by using
a suitable window function. The window function also influences the frequency se-
lectivity and the spectral error. The choice of window functions is a compromise be-
tween side-band suppression and width of the spectral lines.
6
Figure 8: FFT menu

Window functions and their effect in the frequency spectrum
Square
Particularly suitable for closely spaced frequency components
Hann
Especially suitable for narrowband sinusoidal signals
Hamming
Particularly suitable for closely spaced frequency components
Flattop
Especially suitable for measurements with good amplitude accuracy
Figure 9: Window functions used in the VM 00 (Wikimedia Commons)
7

veraging of 2 to 6 spectra can be performed. This can significantly reduce the
"noise carpet" contributed by random signal components and improve the sharpness
of the displayed spectrum. Averaging has a disadvantageous effect on the reaction
time after signal changes.
With the key averaging can be restarted.
With Hold max. the previous FFT is not deleted, but displayed one above the other
(Figure 20). This allows changes in the spectral composition of the signal to be
made visible. The previous spectra appear in darker colors.
In the Triggering menu, you can define the conditions under which a frequency
analysis is performed.
•Auto: The calculation is carried out continuously in the time interval determined
by the frequency resolution.
•DIG : The calculation is performed when a pulse is detected at the RPM input.
•Amplitude: Calculation is performed when an amplitude within the spectrum ex-
ceeds the specified limit value. The limit value is entered as a numerical value
below the trigger menu.
Bandwidth can be switched between 4.5 and 22 kHz. This is the highest measur-
able frequency. A bandwidth of 4.5 kHz is useful if higher frequencies are not of in -
terest. It increases the frequency resolution. With the same resolution the measure-
ment becomes faster.
Gain can be selected between automatic gain and the fixed gains of , 0 and 00.
For most applications the "Auto" setting is recommended. Only in the case of
strongly fluctuating amplitudes is a fixed gain can be more suited to avoid continu-
ous switching.
8
Figure 20: FFT with active hold function