INSTRUCTION MANUAL
Vibration Meter
VM-83
3-20-41 Higashimotomachi, Kokubunji, Tokyo 185-8533, Japan
http://www.rion.co.jp/english/
Organization of this manual
This manual describes the features and operation principles of the vibration meter
VM-83. For information regarding the operation of other equipment in the case of
incorporating the VM-83 into a measurement system with other equipment, always
make sure refer to the documentation of the other equipment.
The page iii and follows contain important information on safety. Be sure to read
this part.
This manual contains the following sections.
Outline
Gives basic information on the con guration and features of the unit, and
contains a block diagram.
Controls and Features
Brie y identi es and explains all parts of the unit.
Preparations
Describes installation, connections, inserting batteries, pre-use checks and
other steps.
Measurement
Describes the steps for measurement.
Comparator
Describes how to use the comparator function.
Printer
Gives information on a printer that can be connected to the unit.
Serial Interface
Describes how to use the serial interface for connection to a computer.
Tec hni ca l Infor mat io n
Provides additional information that is helpful for using the unit.
Speci cations
Lists the technical speci cations of the unit.
Index
Index to the contents of the manual.
* All company names and product names mentioned in this manual are
trademarks or registered trademarks of their respective owners.
i
This item is classi ed as “a regulated product or regulated tech-
nology in the Foreign Exchange and Foreign Trade Control Act”.
Export of this item from Japan requires an export license from the
Government of Japan.
The product described in this manual is in conformity with the
following European standards;
Note: CE requirements are met provided that a core lter is tted to
every cable.
The measurement result may be in uenced when the instrument is used
in a radio-frequency electromagnetic (RFE) eld.
This product can be used in any areas including residential areas.
To conform to the EU requirement of the Directive
on Waste Electrical and Electronic Equipment, the
symbol mark on the right is shown on the instru-
ment.
ii
FOR SAFETY
In this manual, important safety instructions are specially marked as shown
below. To prevent the risk of injury to persons and severe damage to the unit
or peripheral equipment, make sure that all instructions are fully understood
and observed.
Caution
Important
Note
Disregarding instructions
printed here incurs the risk of
injury to persons and/or dam-
age to peripheral equipment.
Disregarding instructions
printed here incurs the risk of
damage to the product.
Mentioned about the tips to
use this unit properly. (This
messages do not have to do
with safety.)
iii
iv
Usage Precautions
Operate the unit only as described in this manual.
Take care not to drop the unit, and protect it from shocks and vibrations.
Do not store or use the unit in locations where the unit may be subject to
- splashes of water or high levels of dust,
- air with high salt or sulphur content, or other gases or chemicals,
- high temperature or humidity (50°C or above, 90%RH or above), or
direct sunlight,
- directly transmitted vibrations or shock.
Observe the following precautions after using the unit:
- Always switch off the power.
- When the unit is not to be used for an extended period, remove the
batteries to prevent possible damage caused by battery leakage.
Do not disassemble the unit or attempt internal alterations.
Have the unit checked and serviced regularly within one or two years.
(Sensitivity calibration can be performed at the factory for a fee.)
When powering the unit externally, use only the speci ed AC adapter
(option). Using a different adapter may cause malfunction or damage.
Do not tap the LCD panel for example with your nger or a pen, to prevent
possible malfunction or damage.
In case of malfunction, do not attempt any repairs. Note the condition of
the unit clearly and contact the supplier.
When disconnecting cables, always hold the plug and do not pull the
cable. Do not apply excessive force.
When disposing of the unit or the accessories, follow national and local
regulations regarding waste disposal.
v
Contents
FOR SAFETY ............................................................................... iii
Outline ............................................................................................1
Controls and Features ......................................................................3
Front panel ................................................................................3
Rear panel .................................................................................5
Side panel .................................................................................7
Display .....................................................................................8
Preparations ..................................................................................11
Power supply ...........................................................................11
Inserting batteries ...................................................................11
AC adapter ..............................................................................12
Using the prop-up feet ............................................................ 13
Selecting an accelerometer ...................................................... 14
Connecting the accelerometer .................................................15
Setting the INPUT SELECT switch .........................................17
Accelerometer sensitivity calibration .....................................18
Measurement .................................................................................20
Power-on .................................................................................20
Measurement mode setting ..................................................... 21
Display characteristics setting .................................................22
High-pass lter setting ............................................................23
Low-pass lter setting .............................................................24
Level range setting ..................................................................25
Menu settings ..........................................................................27
Calibration ..............................................................................31
Maximum value hold .............................................................. 33
Peak hold ................................................................................36
Comparator ...................................................................................38
Printer ........................................................................................... 43
vi
Serial Interface .............................................................................. 47
Transmission principle ............................................................47
Local mode/Remote mode ......................................................48
Transfer protocol .....................................................................50
Error processing .....................................................................52
Control operation in remote mode ...........................................53
Command format ....................................................................54
Technical Information ...................................................................69
Noise level and measurement range ........................................69
Delay of output signal .............................................................73
Rack mounting ........................................................................73
Accelerometer installation ......................................................74
Display range ..........................................................................76
Aliasing effect ........................................................................77
Filter characteristics ................................................................78
VM-83PB1 software ...............................................................80
Speci cations ................................................................................ 81
Index .............................................................................................93
vii
viii
Outline
The VM-83 is a vibration meter designed for measurement and evaluation
of vibrations, using a piezoelectric accelerometer or a servo accelerometer.
It provides four types of input connectors and allows selection of accelera-
tion, velocity, and displacement measurement. With the optional servo ac-
celerometer, even very low frequency vibrations in the range of 0.1 to 1 Hz
can be measured, something that is very hard to achieve with conventional
piezoelectric accelerometers.
Display characteristics can be switched to rms, equivalent peak, and equiva-
lent peak-to-peak. Peak hold and max. hold functions are also available, and
a comparator with level evaluation output is also available.
AC output, DC output, and a serial interface are provided as standard equipment.
The unit uses a box-type design that makes it easily portable, and it can be
powered from the AC adapter or from batteries.
1
Outline
PICKUP
(ACCELEROMETER)
PREAMP1
PREAMP2
SERVO
Amplifier
Attenuator
Charge
amplifier
Regulated
power supply
18 V 2 mA
Gravity acceleration
canceling circuit
Amplifier
Amplifier
Amplifier
AC OUT
EXT 6 V
IEC R14 (size C)
battery × 4
LPF
OVER
Interface
A/D
ROM
I/O
DC/DC
converter
Block diagram
DSP
CPU
EEPROM
D/A
LCD driver
Amplifier
DC OUT
LCD
2
Controls and Features
Front panel
LEVEL RANGE keys
Serve for switching the level range up ( ) or down ( ).
Display backlight key (LIGHT key)
Serves for turning the display backlight on and off.
When the unit is operating on batteries, the display automatically turns
itself off after 60 seconds. When the batteries are run down, the display
will be darker.
Calibration key (CAL key)
This key turns the calibration signal supplied at the AC and DC outputs on
and off. The signal is used to perform calibration of external equipment.
Accelerometer sensitivity key (PICKUP SENS key)
Serves for setting the accelerometer sensitivity. When the accelerometer
sensitivity setting mode is on, the indicator above the key lights.
3
Controls and Features
MENU key
Allows changing the menu by selecting a menu number. If this key is
pressed in remote mode, the remote mode is canceled and the unit returns
to the local mode.
Power switch
Serves to turn the unit on and off.
COMP ON/OFF key
Serves to turn the comparator function on and off.
HOLD RESET key
Serves for resetting maximum hold data and peak hold data, as well as
the comparator output.
Low-pass lter key (LPF key)
Serves for activating the low-pass lter (indicator above the key lights).
MAX HOLD ON/OFF key
Serves to turn the maximum value hold function on and off.
High-pass lter key (HPF key)
Serves for activating the high-pass lter (indicator above the key lights).
Accelerometer input connector (PICKUP connector)
The piezoelectric accelerometer is to be connected here.
Setting keys
Serve to set the measurement mode, display characteristics, low-pass
lter, high-pass lter, and accelerometer sensitivity. The keys will affect
the function for which the key indicator is lit. The keys are also used for
changing menu settings.
Measurement mode selector key (ACC/VEL/DISP key)
Serves to change the measurement mode (indicator above the key lights).
Display characteristics selector key (RMS/EQPEAK/EQP-P key)
Serves to change the display (detection) characteristics (indicator above
the key lights).
Display
Shows measurement values and various key settings.
4
Rear panel
Controls and Features
BATT BOX
Battery holder
Preamplifier 1
input connector
PREAMP 1
LOCK UNLOCK
PREAMP 2
AC OUT
DC OUT
Preamplifier 2
input connector
Servo input
connector
SERVO(LS-10C)
INPUT SELECT
PREAMP 2
PREAMP 1
PICKUP
SERIAL COMP OUT
SERVO
EXT 6V
SERVO
Serial interface
connector
ACOM
Battery holder
Four IEC R14 (size C) batteries are inserted here.
Battery holder button
Push this button to lock or unlock the battery holder.
Battery holder button
AC output connector
DC output connector
External power
supply connector
Comparator
output terminals
Input select switch
AC output connector
An AC signal corresponding to the measurement value is available at this
connector (full-scale point: 2 V, output impedance approx. 600 ohms).
DC output connector
A DC signal corresponding to the measurement value is available at this
connector (full-scale point: 2 V, output impedance approx. 600 ohms).
External power supply connector
The AC adapter (option) can be connected here.
5
Controls and Features
Comparator output terminals
The comparator signal is available at these terminals. The maximum
applied voltage is 24 V, and the maximum drive current varies as follows
depending on the applied voltage.
Input select switch
Serves to select the input source. Available settings are PICKUP / PRE-
AMP 1 / PREAMP 2 / SERVO / SERVO .
Serial interface connector
Serves for connection of a computer or printer.
Servo input connector (SERVO connector)
50 mA (when the applied voltage is 24 V)
25 mA (when the applied voltage is 12 V)
10 mA (when the applied voltage is 5 V)
The servo accelerometer (LS-10C or LS-20C) can be connected here.
Preampli er 2 input connector (PREAMP 2 connector)
A piezoelectric accelerometer with integrated preampli er can be con-
nected here.
Preampli er 1 input connector (PREAMP 1 connector)
A piezoelectric accelerometer can be connected here via a preampli er.
6
Side panel
Controls and Features
7
Controls and Features
Display
For explanation purposes, the illustration below shows all display elements.
In actual use, not all elements will be seen together.
COMP indicator
This indicator appears when the comparator function is selected.
REMOTE indicator
This indicator appears when the unit is being controlled remotely over
the serial link.
OVER indicator
This indicator appears when the input signal has caused overload.
8
Controls and Features
Units indicator
The unit applicable to the current measurement mode is shown here.
2
m/s
When a piezoelectric accelerometer is used, this indicator
appears during acceleration measurement.
mm/s2 When a servo accelerometer is used, this indicator appears
during acceleration measurement.
mm/s This indicator appears during velocity measurement.
mm This indicator appears during displacement measurement.
pC/(m/s2) This indicator appears during sensitivity setting for the
piezoelectric accelerometer.
Low-pass lter indicator
Shows the low-pass lter setting.
High-pass lter indicator
Shows the high-pass lter setting.
RMS/EQPEAK/EQP-P indicators
Shows the display (detection) characteristics setting.
Measurement value
Shows the current measurement value, maximum hold value, peak hold
value, menu settings, etc.
PEAK/MAX HOLD/OVER indicators
When the maximum hold function has been activated, the MAX HOLD
indicator is displayed (see page 33).
When the peak hold function has been activated, the PEAK HOLD indi-
cator is displayed (see page 36).
When the hold value has exceeded the measurement maximum, the OVER
indicator is displayed.
Bar graph
When the level range setting is 10000, 1000, 100, 10, 1, 0.1, or 0.01, the
indication follows the upper scale: 0, 2, 4, 6, 8, 10.
When the level range setting is 3000, 300, 30, 3, 0.3, 0.03, or 0.003, the
indication follows the lower scale: 0, 1, 2, 3.
The bar graph indication corresponds to the input level.
9
Controls and Features
UNDER indicator
This indicator appears when the input signal has fallen below the mea-
surement threshold.
Battery capacity indicator
Shows the remaining capacity of the batteries.
CAL indicator
This indicator appears during calibration.
Level range indicator
Shows which level range has been selected.
10
Preparations
Power supply
This unit can be operated either on four IEC R14 (size C) batteries or an AC
adapter (option).
Inserting batteries
Unlock the battery holder by pressing
the battery holder button and pull out
the battery holder. After replacing
the batteries, push the battery holder
back into the unit. Be sure to lock t he
holder by pressing the battery holder
button again.
Important
- While inserting or removing batteries, support the battery holder
by hand.
- Take care not to insert batteries with wrong polarity.
- While not using the unit, the batteries should be removed.
- When opening the battery holder, take care that no foreign objects
or dirt get deposited in the holder.
- Do not mix old and new batteries, or different types of batteries.
11
Preparations
Battery life
Alkaline batteries LR14 approx. 20 hours
Manganese batteries R14P approx. 9 hours
When the backlight is used, battery consumption will be about 20% higher.
When the servo accelerometer is connected, current consumption increases
by about 15%.
* The above values were determined under the following conditions.
20°C 50% RH, accelerometer PV-85, ACC, HPF OFF, LPF OFF,
backlight OFF, switch LEDs OFF, communications OFF (MENU
0-0), continuous operation
* The actual battery life will differ, depending on the accelerometer,
settings, ambient conditions, and battery type or battery manufactures.
Remaining battery capacity indication
The following indication appears on the display, depending on the battery
status.
When the battery capacity indicator start to ash,
replace the batteries immediately with a fresh set.
While the indicator is ashing, the measurement
will not be accurate.
AC adapter
The unit can be powered from the following adapter: NC-98 series (option)
Note
12
Connect the cable from the AC adapter to the external power supply connector
on the rear panel.
Using the prop-up feet
The unit can be tilted by ipping out the prop-up feet. Tilt the feet until they
snap in place.
When using the prop-up feet, do not place
objects on top of the VM-83 and do not push
down on the unit.
Preparations
Important
13
Preparations
Selecting an accelerometer
The VM-83 can use piezoelectric accelerometer or servo accelerometer. Select
the type of accelerometer according to the intended measurement range, vi-
bration frequency range, environmental conditions, and other related factors.
- Some major piezoelectric accelerometers made by Rion (representative
values)
General High-output Light weight Heat-resistant 3-axis
Model PV-85 PV-87 PV-90B PV-65 PV-93
Charge sensitivity
(pC/(m/s2) )
Mounting resonance
frequency (kHz) *1
Vibration frequency
range (Hz)
Temp erat ure range
(°C)
Mass (g) 23 115 1.2 26 28
Construction principle Shear type Shear type Shear type Shear type Shear type
6400.1570.7
24 9 70 25 30*
1 to 7000 1 to 3000 1 to 25000 1 to 9000 1 to 8000*
-50 to +160 -50 to +160 -50 to +160 -50 to +260 -50 to +160
2
*1 When mounted with speci ed screws at speci ed torque
*2 Vertical direction value
- Servo accelerometer
The servo accelerometer model that can be used with the VM-83 is
the LS-10C or LS-20C.
2
14
Model LS-10C LS-20C
Voltage sensitivity (V/[m/s
2
]) 0.300 0.300
Vibration frequency range DC to 100 Hz DC to 100 Hz
Temperature range (°C) -20 to +60 -20 to +60
Mass (g) 220 125
Connecting the accelerometer
Before connecting the accelerometer, turn power to
the unit OFF.
Piezoelectric accelerometer
Direct connection
Use the cable supplied with the accelerometer (VP-51 series) to connect
the accelerometer to the accelerometer input connector on the VM-83.
Because the input circuit is con gured as a charge ampli er, accelerometer
cable length has almost no effect on sensitivity.
However, a long cable may lead to an increase in
internal noise. The cable run should therefore be
Preparations
Note
kept as short as possible.
If the cable length exceeds 5 meters, the use of a
preampli er is recommended.
Connection via a preampli er
When the accelerometer is to be installed at a remote location, a pream-
pli er should be used to minimize noise and susceptibilit y to inter ference.
The preampli er shou ld be located close to t he
accelerometer, and the longer cable run should
be between the preampli er and the VM-83.
Use the cable supplied with the accelerometer
(VP-51 series) to connect the accelerometer
to the input of the preampli er (VP-26A etc.).
Connect the output of the preampli er to the
PREAMP 1 input connector on the VM-83,
using a cable of the EC-02S series.
15
Preparations
EC-02S series cables are available in four different lengths, as listed below.
Choose the cable that is most suitable for your application.
Connection of an accelerometer with built-in preampli er
Ty pe L en gt h Ty pe L en gt h
EC-02S 3 m EC-02SD 50 m (with reel)
EC-02SB 10 m EC-02SE 100 m (with reel)
When using an accelerometer with built-in pream-
pli er (PV-41, PV-42), use the cable supplied with
the accelerometer (VP-51 series) to connect the
accelerometer to the PREAMP 2 input connector
on the VM-83.
Servo accelerometer LS-10C or LS-20C
Connecting the servo accelerometer LS-10C or LS-20C
Use a cable of the EC-40 series to connect the
accelerometer to the SERVO input connector on
the VM-83.
Ty pe L en gt h Ty pe L en gt h
EC-40A 5 m EC-40C 30 m (with reel)
EC-40B 10 m EC-40D 50 m (with reel)
16
Setting the INPUT SELECT switch
Set the INPUT SELECT switch as required for the type of input that is being
used.
Preparations
PREAMP 2
SERVO(LS-10C)
SERIAL COMP OUT
INPUT SELECT
PREAMP 2
PREAMP 1
PICKUP
SERVO
SERVO
DC OUT
EXT 6V
ACOM
INPUT SELECT switch
PICKUP : Signal from Accelerometer input connector on front panel
PREAMP1 : Signal from PREAMP 1 connector on rear panel
PREAMP2 : Signal from PREAMP 2 connector on rear panel
SERVO : Signal from SERVO connector on rear panel. Servo ac-
celerometer set to vertical axis.
SERVO : Signal from SERVO connector on rear panel. Servo ac-
celerometer set to horizontal axis.
Note
During calibration, comparator operation, maximum
hold and peak hold, changing the setting of the INPUT SELECT switch has no effect.
17
Preparations
Accelerometer sensitivity calibration
Important
Different accelerometers have different sensitivity. Be sure to perform sensitivity calibration.
Sensitivity calibration
1. Set the INPUT SELECT switch as required.
2. Set the power switch to ON.
3. Press the accelerometer sensitivity key (PICKUP SENS key) on the
front panel. (The indicator above the key lights up and the sensitivity
value ashes.)
18
Preparations
4. Use the setting keys ( , ) to set the display indication to the value
indicated as charge sensitivity on the calibration chart of the accel-
erometer.
When an accelerometer with integrated preampli er is used, enter
the voltage sensitivity. For example, when the voltage sensitivity is
5.90 mV/(m/s
2
), use the value 5.90 pC/(m/s2).
For the servo accelerometer LS-10C or LS-20C, enter the value ac-
cording to the calibration data (approx. 0.300).
When using the preampli er VP-26A, set the charge sensitivity.
Holding one of the setting keys down for more than 2 seconds causes
the display value to change quickly.
19
Power-on
When the unit is turned on, the same settings as used before the unit was
turned off are reestablished ( resume function), and measurement starts. The
level range, high-pass lter setting, low-pass lter setting, and display char-
acteristics are memorized for each measurement mode.
Measurement
Settings memorized by
resume function
Measurement mode CAL status
Level range Maximum value hold
Display characteristics Peak hold
High-pass lter Backlight status
Low-pass lter Sensitivity setting status
Sensitivity MENU setting status
MENU0 to MENU2 item settings Comparator status
MENU4 to MENU8 item settings Remote status
* These measurement conditions are not memorized by the resume
function. They will be reset to the default vibration measurement
condition when the unit is turned on.
Settings made via the serial interface are not memorized for the resume function.
Settings reset at regular
vibration measurement start*
Note
20
Measurement mode setting
Select the measurement mode from ACC (acceleration), VEL (velocity), or
DISP (displacement).
Setting procedure
1. Press the ACC/VEL/DISP key. (The indicator above the key lights
up.)
Measurement
2. Use the setting keys (
, ) to select from ACC VEL DISP.
ACC (acceleration) : m/s2, mm/s
VEL (velocity) : mm/s
DISP (displacement) : mm
The unit for acceleration (ACC) measurement depends on the setting of the INPUT SELECT switch.
PICKUP, PREAMP 1, PREAMP 2 : m/s
SERVO , SERVO : mm/s
2
Note
2
2
21
Measurement
Display characteristics setting
Select the display (detection) characteristics from RMS, EQPEAK, or EQP-P.
Setting procedure
1. Press the RMS/EQPEAK/EQP-P key. (The indicator above the key
lights up.)
2. Use the setting keys ( , ) to select from RMS EQPEAK
EQP-P.
RMS : Effective value
EQPEAK : Equivalent peak value
EQP-P : Equivalent peak-to-peak value
The equivalent peak value and equivalent peak-to-peak value are
calculated according to the following formula.
Equivalent peak value = rms ×
Equivalent peak-to-peak value = equivalent peak value × 2
22
High-pass lter setting
Setting procedure
1. Press the HPF key. (The indicator above the key lights up.)
2. Use the setting key ( , ) to select the lter setting. The available
Measurement
settings are listed below.
Piezoelectric accelerometer
1 Hz, 3 Hz, 10 Hz, 20 Hz, 50 Hz, -- (OFF; ACC only)
Servo accelerometer
0.1 Hz, 0.3 Hz, 1 Hz
For more information on the characteristics of the high-pass lter, please
refer to the Technical Information (see page 78 and 79).
23
Measurement
Low-pass lter setting
Setting procedure
1. Press the LPF key. (The indicator above the key lights up.)
2. Use the setting keys ( , ) to select the lter setting. The available
settings are listed below.
Piezoelectric accelerometer
100 Hz, 300 Hz, 1 kHz, 3 kHz, 10 kHz, -- (OFF; ACC only)
Servo accelerometer
50 Hz, 100 Hz
For more information on the characteristics of the low-pass lter, please refer
to the Technical Information (see page 78 and 79).
24
Level range setting
Set the level range as follows.
Use the LEVEL RANGE keys ( , ) to select an appropriate level range.
The relationship between INPUT SELECT switch, accelerometer sensitiv-
ity, measurement mode, and HPF is shown in the table on the next page.
Measurement
25
Measurement
- When INPUT SELECT switch is set to PICKUP, PREAMP 1, or
PREAMP 2
(*0 HPF: 1 Hz; *1 HPF: 3 Hz; *2 HPF: 10 Hz or above)
Sensitivity
0.030
to
0.999
pC/(m/s
2
)
1.00
to
9.99
pC/(m/s
2
)
10.0
to
99.9
pC/(m/s
2
)
Measurement
mode
Level range
ACC 3 10 30 100 300 1000 3000 10000
VEL 30 100 300 1000 3000 10000 - -
0
DISP*
DISP*
DISP*
1
2
- 10 30 100 300 1000 3000 10000
3 10 30 100 300 1000 3000 10000
0.3 1 3 10 30 100 300 1000
ACC 0.3 1 3 10 30 100 300 10 0 0
VEL 3 10 30 10 0 300 1000 - -
0
DISP*
DISP*
DISP*
1
2
- 1 3 10 30 100 300 1000
0.3 1 3 10 30 100 300 1000
0.03 0.1 0.3 1 3 10 30 100
ACC 0.03 0.1 0.3 1 3 10 30 100
VEL 0.3 1 3 10 30 100 - -
DISP*
DISP*
DISP*
0
1
2
-0.10.3131030100
0.03 0.1 0.3 1 3 10 30 100
0.003 0.01 0.03 0.1 0.3 1 3 10
Sensitivity
0.100
to
0.999
26
- When INPUT SELECT switch is set to SERVO or SERVO
Measurement
mode
ACC 10 30 100 300 1000
VEL 1 3 10 30 100
DISP 0.1 0.3 1 3 10
Level range
Menu settings
The settings for the serial interface, printer, peak hold function, and compar-
ator function are made via menus.
Measurement
1. Call up the menu screen.
If one of the keys CAL, COMP ON/OFF, or MAX
HOLD ON/OFF is set to ON, the menu screen will
not appear.
Note
27
Measurement
2. When the MENU key is pressed, a menu screen as shown below
appears.
With each push of the MENU key, the menu number cycles through
0
1 2 3 4 5 6 7 8 measurement
screen.
3. Select the number of the desired menu, and use the setting key ( , )
to change the displayed value.
Menu contents
Menu 0
Serial interface and printer function ON/OFF
0-0 Serial interface and printer function OFF. Choose this
0-1 Serial interface ON
0-2 Printer function ON
Menu 1
Serial interface and printer transfer rate
Note
The new setting will become effective when switching back from the menu screen to the measurement
screen.
setting when using neither the serial interface nor the
printer function.
28
1-96 Transfer rate 9600 bps
When the printer function is set to ON, select the 1-96
setting.
1-19 Tra nsfer rate 19200 bps
Menu 2
Serial interface ID number
Measurement
2-
Choose a setting from 0 to 15.
Menu 3
Peak hold function ON/OFF
3-0 Peak hold function OFF
3-1 Peak hold function ON
Menu 4
Comparator function and comparator level
Sets the comparator function and chooses a level between 0 and 98% of
the full-scale value, in 2% steps
4- Choose a setting from 0 to 98 in steps of 2.
Menu 5
Delay time for comparator function
Sets the delay time in the range from 0 to 9 seconds
5- Choose a setting from 0 to 9 in steps of 1.
Menu 6
Comparator function auto reset ON/OFF
6-0 Auto reset function OFF
6-1 Auto reset function ON
Menu 7
Auto reset time for comparator function
When auto reset has been set to ON with menu 6, this setting determines
the auto reset time in the range from 0 to 90 seconds, in 1 second steps
7- Choose a setting from 0 to 90 in steps of 1.
29
Measurement
Menu 8
Comparator output buzzer
This controls buzzer use for the comparator function. When enabled, the
buzzer sounds while the comparator output is active. When disabled, there
is no buzzer sound also when the comparator output is active.
8-0 Buzzer disabled
8-1 Buzzer enabled
Note
The settings for menu number 0 to 2, and 4 to 8 will
be retained also while the unit is turned off.
Menu number Setting
0-0 Serial interface and printer OFF
0
0-1 Serial interface ON
0-2 Printer ON
1-96 9600 bps
1
1-19 19200 bps
2
2-
ID number setting 0 to 15
3-0 Peak hold OFF
3
3-1 Peak hold ON
4
5
4-
5-
Compa rator level sett ing 0 to 98 (in 2 steps)
Delay time setting 0 to 9
6-0 Auto reset OFF
6
6-1 Auto reset ON
7
7-
Auto reset time setting 0 to 90
8-0 Buzzer disabled
8
8-1 Buzzer enabled
30
Calibration
When using external equipment to record the AC output signal or DC output
signal of the VM-83, perform calibration as follows.
Measurement
In the CAL (calibration) state, the range full-scale signal is output from the
AC output connector and DC output connector.
31
Measurement
(1) When INPUT SELECT switch on rear panel is set to PICKUP, PRE-
AMP 1, or PREAMP 2
AC output connector (AC OUT) : 80 Hz, 2 V*
DC output connector (DC OUT) : 2 V
(2) When INPUT SELECT switch on rear panel is set to SERVO
SERVO
AC output connector (AC OUT) : 1 Hz, 2 V *
DC output connector (DC OUT) : 2 V
Pressing the CAL key again turns the calibration mode off.
* AC output signal in calibration mode
Display characteristics RMS : 2 Vrms output
EQPEAK : 2 Vpeak output
EQP-P : 2 Vp-p output
Note
In calibration mode, all controls except the LIGHT
key, CAL key, and power switch are inactive.
To enable correct output of the calibration signal
when the CAL key is pressed, the following settings
are required.
- COMP ON/OFF : OFF
- MAX HOLD ON/OFF : OFF
- Menu 3, Peak hold ON/OFF : OFF
or
32
When the range setting is 0.03, 0.3, 3, 30, 300, or
3000, the range full-scale value is 0.0316, 0.3162,
3.162, 31.62, 316.2, or 3162, respectively.
Maximum value hold
This function serves for holding the maximum measured value.
Setting procedure
1. Press the MAX HOLD ON/OFF key to set the function to ON.
Measurement
2. When the maximum hold function is ON, the indication MAX HOLD
appears on the display, and the indicated numeric value is the max-
imum value measured up to that point. When a higher value occurs,
the display is updated.
33
Measurement
3. When the maximum hold value is higher than the overload threshold,
the indication MAX HOLD OVER is shown.
4. The HOLD RESET key can be used to reset the maximum hold value
at any time.
34
Measurement
5. Pressing the MAX HOLD key again turns the maximum hold mode
off. The unit returns to normal measurement.
Note
While the maximum hold function is ON, all controls
except the LIGHT key, MAX HOLD ON/OFF key,
HOLD RESET key, and power switch are inactive.
The maximum hold function applies only to the
numeric display. The bar graph indication continues
to function as during normal measurement.
35
Measurement
Peak hold
The peak hold function uses 51.2 kHz sampling on the vibration input signal
to determine the peak value.
Setting procedure
1. Use the MENU key to call up menu 3.
2. Use the setting keys to select the setting 3-1 (peak hold ON).
3. Return to the measurement screen.
4. When the peak hold function has been activated, the indication PEAK HOLD appears
on the display, and the indicated numeric value is the peak value measured up to that
point. When a higher peak occurs, the display is updated.
When the peak hold value is higher than the overload threshold, the indication PEAK
HOLD OVER is shown.
5. The HOLD RESET key can be used to reset the peak hold value at
any time.
36
The peak hold function applies only to the numeric
display. The bar graph indication continues to function as during normal measurement.
While the peak hold function is ON, all controls
except the LIGHT key, MENU key, HOLD RESET
key, and power switch are inactive.
Turning the peak hold function off
Set the menu 3 item to 3-0.
The peak hold function is available only for ACC
(acceleration) measurement.
Measurement
Note
Note
The bar graph continues to operate with the display
characteristics (acceleration) as selected before activating peak hold.
37
Comparator
Comparator operation
The comparator works by constantly monitoring the measured vibration
level and comparing it to a preset reference level (comparator level). If the
comparator level is exceeded, the comparator output becomes active (open
collector circuit, LCD ashing, buzzer sounds).
To turn the comparator function on and off, use the COMP ON/OFF key.
Pressing the COMP ON/OFF key once turns the function on and pressing it
once more turns it off again.
The various settings for the comparator function are made via menu screens
(see “Menu Settings” on page 27).
Setting items
Comparator level 0 to 98% in 2% steps
Delay time 0 to 9 seconds in 1 s steps
Auto reset function
Auto reset time 0 to 90 seconds in 1 s steps
Buzzer
38
Comparator
While comparator function is operating, the COMP indicator is shown.
In the bar graph indication, the bar corresponding to the comparator reference
level remains constantly on.
Comparator level
The comparator level is the threshold where the comparator output becomes
active. This setting is made with menu 4. (See “Menu settings” on page 27.)
For example, if the comparator level is set to 48%, the level corresponding
to 48% of the level scale value is the threshold, and the 48% point of the bar
graph scale is on.
Comparator level indicator
This bar lights for comparator level 48%
2
Actual vibration indication
4
While the comparator function is ON, all controls
except the LIGHT key, HOLD RESET key, COMP
ON/OFF key, and power switch are inactive.
6
8
Note
39
Comparator
Auto reset function
The auto reset f unction is controlled with menu screen 6 (see “Menu Settings”
on page 27).
When the function is set to ON and the vibration level has fallen again below
the comparator level, the comparator output will automatically be reset (turned
off) after the auto reset time has elapsed. When the function is set to OFF,
the comparator output remains on until the HOLD RESET key is pressed or
the comparator function is turned off with the COMP ON/OFF key.
Auto reset time
The auto reset time is set with menu screen 7 (see “Menu Settings” on page 27).
When the function is set to ON and the vibration level falls below the com-
parator level, the comparator output will be reset after this time.
The auto reset time can be set from 0 to 90 seconds in 1 second intervals.
This setting is used when the auto reset function has been set to ON.
Buzzer
This setting controls operation of the buzzer when the comparator is activated.
The setting is made with menu screen 8 (see “Menu Settings” on page 27).
40
Operation
Comparator
Reset operation
When the comparator output was activated, it can be reset in three ways.
(1) Auto reset
As described above, when auto reset is ON, the comparator output
will be turned off automatically after activation when the auto reset
time has elapsed.
(2) HOLD RESET key
Pressing the HOLD RESET key on the front panel immediately resets
the comparator output. This function is independent of the auto reset
ON/OFF setting.
(3) COMP ON/OFF key
Turning the comparator function off by pressing the COMP ON/OFF
key on the front panel immediately resets the comparator output.
With methods (1) and (2), the comparator function remains ON also after
reset. With method (3), the unit returns to normal measurement.
41
Comparator
Comparator output
The comparator output has three elements.
(1) Buzzer is heard (long intermittent beeps). This applies only if the
buzzer function has been set to ON with menu 8.
(2) LCD display ashes.
Measurement value indicator section ashes in 0.5 second intervals.
(3) Open collector circuit operates, causing the comparator output ter-
minals on the rear panel to close.
Circuit block diagram
Maximum drive current: 50 mA (when applied voltage is 24 V)
25 mA (when applied voltage is 12 V)
10 mA (when applied voltage is 5 V)
Maximum applied voltage: 24 V
42
Printer
You can connect an optional printer to produce hard copy of measurement
results. The following printers are compatible with the VM-83:
CP-10, CP-11, DPU-414
Activating printer operation
1. Turn power to the VM-83 and the printer off.
2. Use a generic cable to connect the serial interface connector on the
rear panel of the VM-83 to the printer.
Cable: Straight serial cable (generic)
Connector type on VM-83: 9-pin D-sub, male
Con ne ctor type at pr inter: 25-pin D-sub, fema le (For DPU- 414,
use the connector adapter supplied
with the printer.)
3. Set the DIP switches on the printer as required, then turn on the
printer and set it to ON LINE.
4. Set the power switch of the VM-83 to ON.
5. Using the menu screens, select the menu settings 0-2 and 1-96. When
you switch back from the menu screen to the measurement screen,
printing starts.
43
Printer
Stopping printer operation
1. Using the menu screens, select the menu setting 0-0.
2. Disconnect the cable.
Printer operation is paused during calibration, comparator operation, sensitivity setting, and while using
the menu screens.
DIP switch settings for printers CP-11, CP-10
Set the DIP switches for the respective printers as shown below.
Note
44
Note
Switches 7 and 8 of DIP switch bank 2 of printer CP11 are set individually at the factory before shipping.
DIP switch settings for printer DPU-414
When connecting the printer DPU-414, set the DIP switches 1 to 3 for the
printer software as follows. For more information on making these settings,
please refer to the instruction manual of the DPU-414.
Vibration meter VM-83 (9600 bps)
1OFF
2ON
3ON
Printer
SW-1
SW-2
SW-3
4OFF
5ON
6OFF
7ON
8ON
1ON
2ON
3ON
4ON
5ON
6ON
7ON
8ON
1ON
2ON
3OFF
4ON
5OFF
6ON
7ON
8ON
45
Printer
Printout sample
A set of ve measurement values for every 2 seconds is printed out every 10
seconds as one line.
“ “ is used to indicate an OVER occurrence and “#” an UNDER occurrence.
46
Serial Interface
The VM-83 incorporates a serial interface that can be used to set measurement
parameters and control measurement using commands sent from a computer.
Measurement results can also be sent to the computer.
Transmis sion principle
Transfer principle : asynchronous, half-duplex
Data word length : 8 bit
Stop bits : 2
Parity : none
Baud rate : 9600 bps, 19200 bps
Cable type : Generic cross-wired serial cable (null modem)
Connector on VM-83 9-pin D-sub, male
47
Serial Interface
Local mode/ Remote mode
Local mode
In this mode, the controls on the panel of the VM-83 are used to
operate the unit.
Immediately after being turned on, the unit is always in local mode.
Remote mode
In this mode, the VM-83 operates in response to commands sent f rom
a computer. Only the MENU key and LIGHT key on the VM-83 are
active, all other controls are disabled. The indication REMOTE ap-
pears on the display of the VM-83 when the unit is in remote mode.
Switching between local mode and remote mode
The RMT command is used to switch between local mode and remote
mode.
48
Preparations
1. Turn power to the VM-83 and the computer off.
2. Use a generic cable to connect the serial interface connector on the
rear panel of the VM-83 to the computer.
Cable : Generic cross-wired serial cable
Connector type on VM-83 : 9-pin D-sub, male
Serial Interface
(null modem)
3. Set the power switch of the VM-83 to ON.
4. Make the required menu settings at the VM-83.
For details, please refer to “Menu Settings” on page 27.
Menu 0-1
Menu 1-96 or 1-19 Set transfer rate.
Menu 2-
Set ID number.
49
Serial Interface
Transfer protocol
Sending of commands
In order to control the VM-83 from a computer or to retrieve measurement
data, certain commands must be sent to the VM-83. The data exchange must
be performed according to certain rules, to ensure that both the VM-83 and
the computer recognize the commands and data properly.
To send commands to the VM-83, the following procedure must be observed.
The following explanation assumes that the preparations described on page
49 have been completed.
stands for the ID number.
Example : If the ID number 0 is set, stands for 00.
1. The computer sends RMT1
2. When RMT1
<CR><LF > has been received, the VM-83 returns
<CR><LF> to the VM-83.
<ACK>READY<CR ><LF> to the computer. The link is now estab-
lished, and the indication REMOTE appears on the display of the
VM-83.
3. To change a setting at the VM-83, the computer sends (setting com-
mand) <CR><LF> to the VM-83.
4. When a valid setting command is received by the VM-83, it carries
out the respective processing steps. When these are completed suc-
cessfully, the VM-83 returns an <ACK>READY<CR><LF> to the
computer.
5. To receive data, the computer sends (data request command) <CR><LF>
to the VM-83.
6. When the VM-83 receives a command which requests data, it carries
out the respective processing steps and sends (data) <EOT><CR><LF>
50
to the computer.
7. To terminate the link, the computer sends RMT0
to the VM-83.
<CR><LF>
Serial Interface
is the ID number.
<ACK> : Control code 06H (ack nowledge)
<CR> : Control code 0DH (carriage return)
<LF> : Control code 0AH (line feed)
<EOT > : Control code 04H (end of transfer)
READY : ASCII string
(command) : ASCII string (command and parameters)
(data) : ASCII string (data requested by command)
51
Serial Interface
Error processing
In order to ensure correct data exchange between the VM-83 and the com-
puter, the rules described above must be observed. If an error occurs, the
following steps should be taken.
The computer has sent RMT1
<CR><LF> but the REMOTE indicator
on the VM-83 does not light:
Send RMT1
<CR><LF> again after about 4 seconds. Repeat this
2 to 3 times. If the REMOTE indicator still does not light, one of the
following conditions may exist.
- Transfer parameters do not match. (Check settings made with menu
screens.)
- Interface cable is defective or not properly connected.
- VM-83 is not powered.
- ID number setting does not match.
When the computer has sent a wrong command or the parameter is out of
range, the VM-83 disregards that command. If the VM-83 is in receiving
mode but there is no command from the computer for 4 seconds or more,
the receive mode times out.
52
Control operation in remote mode
While the VM-83 is in remote mode, only the LIGHT key and MENU key
are active. The LIGHT key allows turning the display backlight on and off,
and the MENU key in remote mode serves for switching back to local mode.
This allows manual override of remote mode at any time.
Serial Interface
53
Serial Interface
Command format
Commands that can be used by the VM-83 consist of 3 characters (3 bytes),
usually followed by a parameter which speci es the action range of the
command.
There are two types of parameters:
- Parameters for changing function settings
- Parameter for requesting data
The parameters for changing function settings are numerals, and the param-
eter for requesting data is “?”. In the following command description, the
function setting parameters are denoted by “n”. The data output by the VM-83
in response to the data requesting command are denoted by “p”.
Note
The VM-83 cannot process multiple commands sent
together.
54
Serial Interface
Command list
Command Function See page
RMT n1 n2 n3 Select local mode/ remote mode 56
RMT? Get ID number and remote mode status 56
RNG n Set level range 56
UNT n Set measurement mode 57
DET n Set display characteristics 58
SNS n1 n2 n3 n4 Set sensitivity 58
LPF n Set low-pass lter setting 59
HPF n Set high-pass lter setting 60
CAL n Set calibration mode 61
CAL? Get calibration mode status 61
BAT? Get battery capacity status 61
DOD? Get measurement data 62
DOF n
Output instantaneous value every 0.1
seconds in non-protocol mode
63
MAX n Set maximum hold function to On/Off 64
MAX? Get maximum hold function status 64
PEK n Set peak hold function to On/Off 64
PEK? Get peak hold function status 64
RST Reset hold value 65
CMP n Set comparator function to On/Off 65
CMP? Get comparator function status 65
CMS n1 n2 n 3 n4 n5 n6 n7 Ma ke comparator function setti ngs 66
CMS? Get comparator function settings 66
STS? Get setting information 67
Note
Settings made via the serial interface are not memorized for the resume function (see page 20).
55
Serial Interface
Commands
RMT n1 n2 n3 Select local mode/remote mode
RMT? Get ID number and remote mode status
n1=0 Local mode
n1=1 Remote mode
n2 n3 = 00 to 15, FF
Sets ID number. VM-83 speci ed by ID number
rec eives the command. F F speci es all connected
VM-83.
Output data format
p1 p2 p3<EOT><CR><LF>
p1, p2 is ID number
p3=1 Remote mode
RNG n Set level range
Value of n is determined by INPUT SELECT switch
setting, measurement mode, sensitivity information,
and HPF setting, as shown in table below.
56
Serial Interface
- When INPUT SELECT is set to PICKUP, PREAMP1, PREAMP2
(*0 = HPF 1 Hz, *1 = HPF 3 Hz, *2 = HPF 10 Hz and higher)
Sensitivity
0.030
to
0.999
pC/(m/s
2
1.00
to
9.99
pC/(m/s
2
10.0
to
99.9
pC/(m/s2)
Measurement
mode
n=0 n=1 n=2 n=3 n=4 n=5 n=6 n=7
ACC 3 10 30 100 300 1000 3000 10000
VEL 30 100 300 1000 3000 10000 - -
0
)
DISP*
DISP*
DISP*
1
2
- 10 30 100 300 1000 3000 10000
3 10 30 100 300 1000 3000 10000
0.3 1 3 10 30 100 300 1000
ACC 0.3 1 3 10 30 100 30 0 100 0
VEL 3 10 30 100 300 1000 - -
0
)
DISP*
DISP*
DISP*
1
2
- 1 3 10 30 100 300 1000
0.3 1 3 10 30 100 300 1000
0.03 0.1 0.3 1 3 10 30 100
ACC 0.03 0.1 0.3 1 3 10 30 100
VEL 0.3 1 3 10 30 100 - -
0
DISP*
DISP*
DISP*
1
2
-0.10.3131030100
0.03 0.1 0.3 1 3 10 30 100
0.0030.010.03 0.1 0.3 1 3 10
- When INPUT SELECT is set to SERVO , SERVO
Sensitivity
0.100
to
0.999
Measurement
mode
n=1 n=2 n=3 n=4 n=5
ACC 10 30 100 300 1000
VEL 1 3 10 30 100
DISP 0.1 0.3 1 3 10
UNT n Set measurement mode
n=0 ACC (acceleration)
n=1 VEL (velocity)
n=2 DISP (displacement)
57
Serial Interface
DET n Set display characteristics
n=0 RMS
n=1
EQPEAK
n=2 EQP-P
SNS n1 n2 n3 n4 Set sensitivity
n1 to n3 Set sensitivity to 030 to 999
n4=0 Set sensitivity to 1/10 of value speci ed
with n1 to n3
n4=1 Set sensitivity to 1/100 of value speci ed
with n1 to n3
n4=2 Set sensitivity to 1/1000 of value speci ed
with n1 to n3
Explanation for command SNS n1 n2 n3 n4
n1 to n3 030 to 999 n4 = 0
1
10
1
1
100
1
2
1000
times
times
times
Sensitivity
99.9
10.0
When n4 = 0
9.99
When n4 = 1
58
n4 = 0
1
2
n1 to n3
n1 to n3
999
to
100
999
to
030
1.00
0.03
0.999
When n4 = 2
LPF n Set low-pass lter setting
Command action depends on INPUT SELECT switch
setting.
Piezoelectric accelerometer
PICKUP, PREAMP1, PREAMP2
Servo accelerometer
Serial Interface
SERVO
, SERVO
Piezoelectric Servo
n=0 100 50
n=1 300 100
n=2 1 k 100
n=3 3 k 100
n=4 10 k 100
n=5 OFF 100
n=6* user lter user lter
* This is valid only when the user lter is set up
by using VM-83PB1 software (option).
59
Serial Interface
HPF n Set high-pass lter setting
Command action depends on INPUT SELECT switch
setting.
Piezoelectric accelerometer
PICKUP, PREAMP1, PREAMP2
Servo accelerometer
SERVO
, SERVO
Piezoelectric Servo
n=0 OFF 0.1
n=1 1 0.3
n=2 3 1
n=3 10 1
n=4 20 1
n=5 50 1
n=6* user lter user lter
* This is valid only when the user lter is set up
by using VM-83PB1 software (option).
With piezoelectric accelerometer and measurement
mode VEL or DISP, n = 0 setting is not allowed.
60
CAL n Set calibration mode.
n=0 Calibration OFF
n=1 Calibration ON
CAL? Get calibration mode status
Output data format
p<EOT><CR><LF>
p=0 Calibration OFF
p=1 Calibration ON
BAT? Get battery capacity status
Output corresponds to status of battery capacity indi-
cator on display.
Output data format
p<EOT><CR><LF>
Serial Interface
p=0 Flashing
p=1 1 segment lit
p=2 2 segments lit
p=3 3 segments lit
61
Serial Interface
DOD? Get measurement data
Returns a value corresponding to the display indication.
Output data format
p1 p2 p3 p4 E ± p5, p6 <EOT><CR><LF>
p1 to p4 Effective 4 digits of measurement value
p5=-6 to +1
p6=O (overload occurred)
p6= _ (no overload occurred) (_ is a space)
* Explanation of p5
p5 stands for 10
p5
.
For example, when measurement value is 10000,
p5 will be 1, because 1000 × 101
* When operating in maximum hold mode, returned
value corresponds to MAX HOLD value.
Same applies to peak hold mode.
When this command is received while there is no
display indication, output will be p1 to p4=0000.
62
Serial Interface
DOF n Output instantaneous value every 0.1 seconds in
non-protocol mode
n=0 Instantaneous value output OFF
n=1 Instantaneous value output ON
Data will be output every 0.1 seconds. When DOF 0
is received, non-protocol mode output is terminated.
For information on output data format, see section on
“DOD?”.
DOF communication format
Note
Be cause t h is unit suppor ts only half- duplex communication, it cannot receive and send data at the same
time. When sending the DOF 0 command to the unit,
the computer must use timing which ensures that the
command does not collide with the instantaneous
value data that are being output by the unit.
63
Serial Interface
MAX n Set maximum hold function to On/Off
MAX? Get maximum hold function status
PEK n Set peak hold function to On/Off
PEK? Get peak hold function status
n=0 Maximum hold OFF
n=1 Maximum hold ON
Output data format
p<EOT><CR><LF>
p=0 Maximum hold OFF
p=1 Maximum hold ON
n=0 Peak hold OFF
n=1 Peak hold ON
Output data format
p<EOT><CR><LF>
p=0 Peak hold OFF
p=1 Peak hold ON
64
RST Reset hold value
This command is active during maximum hold, peak
hold, and comparator operation.
CMP n Set comparator function to On/Off
n=0 Comparator OFF
n=1 Comparator ON
CMP? Get comparator function status
Output data format
p<EOT><CR><LF>
p=0 Comparator OFF
p=1 Comparator ON
Serial Interface
65
Serial Interface
CMS n1 n2 n3 n4 n5 n6 n7
CMS? Get comparator function settings
Make comparator function settings
n1 to n2 Comparator level 00 to 98 (steps of 2)
n3 Delay time 0 to 9
n4=0 Auto reset OFF
n4=1 Auto reset ON
n5 to n6 Auto reset time 00 to 90 (steps of 10)
n7= 0 Buzzer OFF
n7=1 Buzzer ON
For items that are not to be changed, send _ (space).
Output data format
p1 p2 p3 p4 p5 p6 p7<EOT><CR><LF>
p1 to p2 Comparator level 00 to 98
p3 0 to 9 (delay time)
p4 0 to 1 (auto reset ON/OFF)
p5 to p6 00 to 90 (auto reset time)
p7 0 to 1 (buzzer ON/OFF)
66
STS? Get setting information
Output data format
p1 p2 p3 p4 p5 p6 p7 p8 p9 p10<EOT><CR><LF>
p1 INPUT SELECT 0 to 4
p1= 0 PICKUP input
p1=1 PREAMP 1 input
p1=2 PREAMP 2 input
Serial Interface
p1=3 SERVO
input
p1= 4 SERVO input
p2 Level range 0 to 7 (RNG n)
p3 Measurement mode 0 to 2 (UNT n)
p4 Display characteristics 0 to 2 (DET n)
p5 to p8 Sensitivity (SNS n1 n2 n3 n4)
p9 High-pass lter setting (HPF n)
p10 Low-pass lter setting (LPF n)
For information on value in brackets, refer to sections
on respective commands.
67
Serial Interface
Allowable remote mode commands in various operation conditions
indicates that command is allowed (valid).
× indicates that command is not allowed (invalid).
Command
RMT n1n2n3
RMT?
RNG n
UNT n
DET n
SNS n1 to n4
LPF n
HPF n
CAL n
CAL?
BAT?
DOD?
DOF n ××××
Normal
measurement
Calibration Comparator
ЧЧЧЧЧ
ЧЧЧЧЧLevel range
ЧЧЧЧЧMeasurement mode
× × × × × Display characteristics
× × × × × Set sensitivity
ЧЧЧЧЧLow-pass lter
ЧЧЧЧЧHigh-pass lter
× × × × × Battery status
× ×Measurement value
Maximum
hold
××××Calibration setting
××××
Peak
hold
DOF
operation
(DOF0)
Explanation
Cancel remote mode
Instantaneous value
(100 ms)
MAX n ××
MAX?
PEK n
PEK?
RST × ×
CMP n
CMP?
CMS n1 to n7
CMS?
STS?
×× ××
×××
××× ×
×
× ×××
× × × × × Comparator setting
ЧЧЧЧЧ
ЧЧЧЧЧSetting information
(CMP0)
68
(MAX0)
× × × Comparator
× × Maximum hold
(PEK0)
×Peak hold
×Reset
Technical Information
Noise level and measurement range
(1) Noise level using accelerometer input and sensitivity 5.00 pC/(m/s2)
(2) Noise level examples using piezoelectric accelerometer input
Accelerometer
type
PV-85
PV-90B
Measurement
mode
Acceleration 0.3 OFF OFF RMS 0.004 m/s
Velocity 3 1 Hz OFF RMS 0.1 mm/s
Displacement 1 1 Hz OFF RMS 0.015 mm
Displacement 0.03 10 Hz OFF RMS 0.0003 mm
Measurement
mode
Acceleration 0.3 OFF OFF RMS 0.0034 m/s
Velocity 3 10 Hz OFF RMS 0.004 mm/s
Displacement 0.03 10 Hz OFF RMS 0.0002 mm
Acceleration 3 OFF OFF RMS 0.133 m/s
Velocit y 30 10 H z OFF R M S 0.17 m m/s
Displacement 0.3 10 Hz OFF RMS 0.007 mm
Measurement
range
Measurement
range
HPF LPF
HPF LPF
Display
characteristics
Display
characteristics
Noise level
Noise level
2
2
2
PV-87
Acceleration 0.03 OFF OFF RMS 0.0005 m/s
Velocity 0.3 10 Hz OFF RMS 0.0006 mm /s
Displacement 0.003 10 Hz OFF RMS 0.00003 mm*
2
* The LCD can display measurement values to four digits after the
decimal point.
69
Technical Information
(3) Measurement range with servo accelerometer LS-10C
Acceleration measurement range
70
Velocity measurement range
Technical Information
71
Technical Information
Displacement measurement range
72
Delay of output signal
The VM-83 directly converts the vibration input signal from analog into
digital form and performs signal processing in the digital domain, using a
DSP. The signal is then reconverted to analog for the AC and DC output. For
this reason, a certain delay is introduced as shown below.
Technical Information
t
For products with the last four digits of the serial number
between 0001 and 2363, t is approx. 600 μs
For products with the last four digits of the serial number
since 2364, t is approx. 900 μs
Rack mounting
The VM-83 can be mounted in a rack, using the four screw holes on the
bottom of the unit.
73
Technical Information
Accelerometer installation
The accelerometer can be mounted to the measurement object in one of the
four general ways outlined below. The accelerometer mounting method greatly
affects the contact resonance frequency *. The advantages and disadvantages
of various methods are described in this section.
Rigid screw mounting
This mounting principle assures optimum frequency response
characteristics. The mounting surface should be perfectly
smooth, and the screw holes (M6) must be drilled in such a
way so as not to disturb perpendicularity of the accelerometer.
Insulation attachment mounting
This mounting principle is used when electrical insulation
between accelerometer and measurement object is required.
The contact resonance frequency will be lower than with
rigid screw mounting. Regarding the screw holes, the same
precautions as for rigid screw mounting apply.
Magnet attachment mounting
Because the contact resonance frequency will be quite low, this
principle is mainly suited for vibration measurements in the
medium to low frequency range. The maximum acceleration
that can be measured depends on the accelerometer mass.
Rod attachment mounting
Pressing the accelerometer against the measurement object
with a rod is the simplest method, but the measurement fre-
quency range would be about several hundred Hz, because the
contact resonance frequency will be very low. This method
should only be used if the other three mounting methods are
74
not feasible.
Note
Tighten the M6 screw rst on the piezoelectric accelerometer side and then mount the rod attachment.
Technical Information
* Contact resonance frequency
Contact resonance occurs when the area where the mounted accelerometer
contacts the measurement object becomes temporarily deformed, causing
it to act like a spring. This spring and the accelerometer mass then form a
system that vibrates at a certain resonance frequency.
The resonance frequency, which varies considerably depending on the mounting
method of the accelerometer, limits the upper range of vibration frequencies
that can be measured.
The diagram below shows the relationship between mounting method and
high range characteristics. This demonstrates that, besides selecting an ap-
propriate mounting method, it is important to set the measurement range so
that the in uence of the contact resonance phenomenon is excluded.
Sample chart showing the in uence of accelerometer mounting method on
high-range frequency characteristics
30
Magnet attachment mounting
20
Rod attachment mounting
10
Response (dB)
0
50 100 200 500 1000 2000 5000 10 k 20 k
Frequency (Hz)
Adhesive
(instant glue)
Screw mounting
75
Technical Information
Display range
This section provides information on the numeric range of the digital display
used in the VM-83.
For simpli cation, the range is assumed to be “100” and “30”, and the display
characteristics setting EQ PEAK. Because the overload point of this unit is
approximately three times the range full-scale point, the display range at
the range “100” setting is about 300, and at the “30” setting (actually 31.6)
is about 90, assuming that there is no overload in the intermediate circuits.
The display resolution is 0.1 and 0.01. Therefore the possible display range
is as follows:
Range Display range
100 0.1 to 30 0.0
30 0.01 to 90.00
The VM-83 directly feeds the raw waveform of the vibration signal to an
A/D converter and then performs lter processing, rms conversion, and
other functions using a DSP. When the number of effective digits for display
decreases, display accuracy cannot be maintained. Therefore the indication
UNDER appears on the display when the displayed value falls below 0.5%
of the full-scale point. This warns the user that the current range setting is
not appropriate. To assure accurate readings, the range setting should be
made so that the UNDER indication does not appear. At a level of 0.2% of
the full-scale point and lower, the lowest bit level of the A/D converter is
reached, so that readings will be indeterminate. At a range “30” setting, this
corresponds to 0.06 and at a range “100” setting, this corresponds to 0.2. This
means that readings below this limit will be highly imprecise, and that the
display reading may not be 0 even if the actual vibration signal is very low.
76
Aliasing effect
The VM-83 directly converts the vibration input signal from analog into dig-
ital form and performs signal processing in the digital domain, using a DSP.
This principle is subject to the so-called aliasing effect. An anti-aliasing lter
(analog low-pass lter) serves to counter this effect. In the VM-83, a 5th-order
lter is used for this purpose. Note that the lter has the effect shown below.
Technical Information
In the above illustration, the shaded section represents the area where the
aliasing effect is noticeable. With fs/2 as the center, the two spectrum repre-
sentations look like mirror re ections of each other.
The arrow (solid line) indicates a case where a signal 1.56 times the 20 kHz
upper measurement limit is input (31.2 kHz). In this case, aliasing will cause
a spectrum level detection of -50 dB (0.3%) at 20 kHz.
77
Technical Information
Filter characteristics
Piezoelectric accelerometer
High-pass lter
Low-pass lter
The above speci cations are a representative example for AC output.
78
Servo accelerometer LS-10C
High-pass lter
Technical Information
Low-pass lter
The above speci cations are a representative example for AC output.
79
Technical Information
VM-83PB1 software
VM-83PB1 is a software package for Microsoft Windows 95, 98, 98SE, Me,
2000, XP and Microsoft Windows NT4.0 which allows controlling settings
and measurement operation of the VM-83 from the computer, via the serial
port. Measurement data downloaded from the VM-83 can be stored in text le
format, allowing further processing for example using a spreadsheet program.
80
Microsoft and Windows are trademarks or registered trademark of Microsoft
U.S.A. Corporation in the U.S.A. and other countries.
Speci cations
Applicable standards
CE marking
Input Section
(1) PICKUP input
For piezoelectric accelerometer (microdot connector)
Maximum input charge 30000 pC
(2) PREAMP 1 input
For piezoelectric accelerometer via preampli er VP-
26A (7-pin female connector PRC-03)
(3) PREAMP 2 input
For piezoelectric accelerometer with integrated pre-
ampli er
18 V, 2 mA drive (microdot connector)
(4) SERVO input
For servo accelerometer LS-10C or LS-20C
(8-pin female connector)
Measurement modes
(1) Acceleration (ACC)
m/s2 (piezoelectric accelerometer), mm/s2 (ser vo ac-
celerometer)
(2) Velocity (VEL) mm/s
(3) Displacement (DISP)
mm
Measurement range
Piezoelectric accelerometer
- Accelerometer sensitivity 0.030 to 0.999 pC/(m/s2)
Acceleration 3, 10, 30, 100, 300, 1000, 3000, 10000 m/s
Velocity 30, 100, 300, 1000, 3000, 10000 mm/s
Displacement 10, 30, 100, 300, 1000, 3000, 10000 mm (HPF 1 Hz)
Displacement 3, 10, 30, 100, 300, 1000, 3000, 10000 mm (HPF 3 Hz)
Displacement 0.3, 1, 3, 10, 30, 100, 300, 1000 mm
2
(HPF 10 Hz or higher)
81
Speci cations
- Accelerometer sensitivity 1.00 to 9.99 pC/(m/s2)
Acceleration 0.3, 1, 3, 10, 30, 100, 300, 1000 m/s
2
Velocity 3, 10, 30, 100, 300, 1000 mm/s
Displacement 1, 3, 10, 30, 100, 300, 1000 mm (HPF 1 Hz)
Displacement 0.3, 1, 3, 10, 30, 100, 300, 1000 mm (HPF 3 Hz)
Displacement 0.03, 0.1, 0.3, 1, 3, 10, 30, 100 mm
(HPF 10 Hz or higher)
- Accelerometer sensitivity 10.0 to 99.9 pC/(m/s2)
Acceleration 0.03, 0.1, 0.3, 1, 3, 10, 30, 100 m/s
2
Velocity 0.3, 1, 3, 10, 30, 100 mm/s
Displacement 0.1, 0.3, 1, 3, 10, 30, 100 mm (HPF 1 Hz)
Displacement 0.03, 0.1, 0.3, 1, 3, 10, 30, 100 mm (HPF 3 Hz)
Displacement 0.003, 0.01, 0.03, 0.1, 0.3, 1, 3, 10 mm
(HPF 10 Hz or higher)
Servo accelerometer
Acceleration 10, 30, 100, 300, 1000 mm/s
Velocity 1, 3, 10, 30, 100 mm/s
Displacement 0.1, 0.3, 1, 3, 10 mm
Vibration frequency range
Piezoelectric accelerometer
Acceleration 1 Hz to 20 kHz ±5%
(AC output: 15 kHz to 20 kHz )
Velocity 1 Hz to 3 Hz ±10%, 3 Hz to 3 kHz ±5%
Displacement 1 Hz to 3 Hz ±20%, 3 Hz to 500 Hz ±10%
Servo accelerometer
Acceleration 0.1 Hz to 100 Hz ±5%
Velocity 0.1 Hz to 0.3 Hz ±10%, 0.3 Hz to 100 Hz ±5%
Displacement 0.1 Hz to 0.3 Hz ±20%, 0.3 Hz to 100 Hz ±10%
2
82
Filters
Piezoelectric accelerometer
HPF OFF, 1, 3, 10, 20, 50 Hz (-10% point), selectable
LPF OFF, 100, 300, 1 k, 3 k, 10 kHz (-10% point), selectable
Servo accelerometer
HPF 0.1, 0.3, 1 Hz, selectable
LPF 50, 100 Hz, selectable
Display (detection) characteristics
Effective value (RMS)
True rms
Speci cations
Equivalent peak value (
EQPEAK)
rms ×
Equivalent peak-to-peak value (EQP-P)
EQPEAK × 2
Maximum value hold Maximum display value for selected measurement mode
and display characteristics is held (numeric display
only). Hold reset key allows reset at any time.
Peak value hold Peak value of acceleration waveform is held.
Comparator function Level evaluation based comparator. Output activated
when comparator level is exceeded
- Comparator level setting
In 2% steps of full-scale value
- Delay time 0 s to 9 s in 1-s steps
- Auto reset time 0 s to 90 s in 1-s steps, ON/OFF
- Comparator output
Open-collector output
Max. applied voltage: 24 V
Max. drive current:
50 mA (when the applied voltage is 24 V)
25 mA (when the applied voltage is 12 V)
10 mA (when the applied voltage is 5 V)
Buzzer output ON/OFF; LCD ashing
83
Speci cations
Display functions
(1) Bar graph linear scale, 100 ms sampled value 0 to 3.16
(2) Measurement value
(3) Measurement mode, display characteristics, lter
(4) Battery status 3-segment indication
0 to 10
4-digit numeric display; arithmetic average of 20 in-
stantaneous values taken at 100 ms intervals, updated
every 2 seconds
84
Calibration
(1) Accelerometer sensitivity
0.030 to 0.999, 1.00 to 9.99, 10.0 to 99.9 pC/(m/s
Shown on display during calibration
(2) Output calibration
Calibration output signal for connected equipment
AC Piezoelectric accelerometer
DC 2 V ±2%
80 Hz ±2%, 2 V ±2%
Servo accelerometer
1 Hz ±2%, 2 V ±2%
2
)
Speci cations
Outputs
(1) AC output Range full-scale 2 V, output impedance 600 Ω, BNC
connector
Load impedance 10 kΩ or higher
Output voltage accuracy
Piezoelectric (unit electrical characteristics, 80 Hz)
Acceleration range full-scale ±2%
Velocity range full-scale ±3%
Displacement range full-scale ±5%
Servo accelerometer
(overall accuracy with LS-10C 1 Hz)
Acceleration range full-scale ±3%
Velocity range full-scale ±4%
Displacement range full-scale ±6%
Max. output voltage ±6 V peak
(2) DC output Range full-scale 2 V, output impedance 600 Ω, BNC
connector
Load impedance 10 kΩ or higher
Output voltage accuracy
Piezoelectric (unit electrical characteristics, 80 Hz)
Acceleration range full-scale ±2%
Velocity range full-scale ±3%
Displacement range full-scale ±5%
Max. output voltage 6 V (4.2 V when rms display is
selected)
(3) Comparator output
Open collector
85
Speci cations
Noise level
(1) Noise level with accelerometer input, sensitivity 5.00 pC/(m/s2)
(2) Noise level examples using piezoelectric accelerometer input
Accelerometer
type
PV-85
PV-90B
Measurement
mode
Measurement
range
HPF LPF
Display
characteristics
Noise level
Acceleration 0.3 OFF OFF RMS 0.004 m/s
Velocity 3 1 Hz OFF RMS 0.1 mm/s
Displacement 1 1 Hz OFF RMS 0.015 mm
Displacement 0.03 10 Hz OFF RMS 0.0003 mm
Measurement
mode
Measurement
range
HPF LPF
Display
characteristics
Noise level
Acceleration 0.3 OFF OFF RMS 0.0034 m/s
Velocity 3 10 Hz OFF RMS 0.004 mm/s
Displacement 0.03 10 Hz OFF RMS 0.0002 mm
Acceleration 3 OFF OFF RMS 0.133 m/s
Velocit y 30 10 H z OFF R M S 0.17 m m/s
Displacement 0.3 10 Hz OFF RMS 0.007 mm
2
2
2
Acceleration 0.03 OFF OFF RMS 0.0005 m/s
PV-87
Velocity 0.3 10 Hz OFF RMS 0.0006 mm /s
Displacement 0.003 10 Hz OFF RMS 0.00003 mm*
* The LCD can display measurement values to four digits after the dec-
imal point.
2
86
(3) Measurement range with servo accelerometer LS-10C
Acceleration measurement range
Speci cations
87
Speci cations
Velocity measurement range
1000
500
200
100
50
20
10
5
Velocity (mm/s rms)
0.1
0.05
0.02
0.01
0.005
0.002
0.001
2
1
0.5
0.2
0.01
0.159 mm /s
0.05
0.02
0.1
0.2 0.5
1.59 Hz
25
1
Frequency (Hz)
10
1.59 mm /s
50
20
100
200 500
1000
88
Displacement measurement range
Speci cations
89
Speci cations
Interface
Serial interface For data output and remote control
9-pin D-sub male connector
Half-duplex communication with protocol
Transfer rate 9600 bps, 19200 bps
Printer output For data output to printer (CP-10, CP-11, DPU-414)
Ambient conditions for operation
−10°C to +50°C, 20% to 90% RH (no condensation)
Power requirements IEC R14 (size C) batteries (×4) or optional AC adapter
NC-98 series
Input voltage range of external power supply connector
5 V to 6.5 V DC
Current consumption
Approx. 190 mA (6 V DC) (*1)
Approx. 60 mA (using AC adapter) (*1, *2)
Battery life for continuous operation
Alkaline batteries (approx. 20 hours) (*1)
Manganese batteries (approx. 9 hours) (*1)
*1 Measurement conditions:
20°C, 50% RH, power supply voltage 6 V, Acceler-
ometer input, ACC, backlight off, communication
off, switch LEDs off
*2 Measurement conditions:
Current consumption measured with AC adapter
at 100 V AC.
Dimensions 171 mm (H) × 120 mm (W) × 234 mm (D)
Weight Approx. 1.8 kg
90
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