CEMB N200 User guide

Vibration equipment division
www.cemb.com
CEMB S.p.A.
Via Risorgimento, 9
23826 MANDELLO del LARIO (Lc) Italy
*Translation of the original instructions
N200
Vibrometer beariNg aNalysis
Use aNd maiNteNaNce iNstrUctioN maNUal

Vibration equipment division
N200 - Ver.1.0 11/2016
General index
1. General description 5
1.1 Standard acceSSorieS 5
1.2 optional acceSSorieS 5
1.3 connectionS 6
1.4 pulSante di reSet 7
1.5 Battery 7
1.6 adjuStment and caliBration 8
1.7 General advice 8
2. General layout 9
2.1 Keypad 9
2.2 S
tart / Stop the acquiSition 10
2.3 Specific additional functionS for the variouS paGeS 10
3. Home screen (menu) 12
4. setup mode 13
4.1 SenSor SenSitivity 13
4.2
date
14
4.3 time 14
4.4 unitS of meaSurement SyStem 14
4.5 diSplay BriGhtneSS 14
4.6 BacKliGhtinG auto-off time 14
4.7 inStrument auto-off time 14
5. Vibrometer mode 15
5.1 meaSurement SettinGS 15
5.1.1 SenSor type 15
5.1.2 MeaSureMent 16
5.1.3 unitS of MeaSureMent 16
5.1.4 type of vibration 16
5.1.5 unitS of frequency 16
5.2 SettinGS only valid for overall meaSurementS 16
5.2.1 frequency range 16
5.2.2 no. of averageS 17
5.3 SettinGS for SynchronouS meaSurementS only 17
5.3.1 SynchronouS filter width 17
5.4 meaSurement reSultS 17
5.4.1 overall MeaSureMent 17
5.4.2 SynchronouS MeaSureMent 18
5.5 additional functionS 20
5.5.1 diSplaying MeaSureMentS froM the recordS 20
6.
tacHometer mode 21
6.1 meaSurement SettinGS 21
6.2 rotation velocity meaSurement 21

N200 - Ver.1.0 11/2016
7. cba cemb bearinG analysis 23
7.1 meaSurement SettinG 23
7.2 cBa meaSurement 23
8
. cemb n-pro proGram (optional) 2
4
8
.1 SyStem requirementS 2
4
8
.2 inStallation of the Software 2
4
8
.3 inStallation of driverS for uSB communication with the n100, n300 inStrumentS
(for verSion 1.3.4 or earlier) 2
5
8
.4 inStallation of driverS for uSB communication with the n100 and n300 inStrumentS
(for
verSion 1.3.5 and later only) 2
6
8
.5 activatinG the Software 2
7
8
.6 uSe of the Software 2
8
7.6.1 function bar 2
8
8
.7 General SettinGS 2
9
8
.8 readinG data from the n100 or n300 inStrument
30
8
.9 data recordS imported from the n100 or n300 inStrument 3
1
8.10 R
eadinG data from the n600 inStrument 3
1
8
.11 diSplayinG data preSent in the recordS 3
2
8
.12 Specific functionS for the Spectrum GraphS 3
2
8
.13 SynchronouS viBration value meaSurement (only for n100 and n300 inStrumentS) 3
3
8
.14 BalancinG data (only for n300 and n600 inStrumentS) 3
4
8
.15 Generation and printinG of certificateS (reportS) 3
4
8
.16 GeneratinG and printinG multiple meaSurement certificateS (multi-report) 3
5

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N200 - Ver.1.0 11/2016
Appendix A
tecHnical data
36
Appendix B
eValuation criteria
37
Appendix C
a rapid Guide to interpretinG aspectrum
38
Appendix D
information related to tHe creation of customised templates (models) for certificates Generated by
cemb n-pro software
44
Appendix E
list of symbols used for tHe instrument
48
Appendix F
errors indicated on tHe display 51

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1. General description
The N200 instrument and its accessories are supplied in a handy case.
We recommend the instrument is returned to its case after every use to protect it from damage during transport.
1.1 standard accessories
• N200 instrument complete with battery
• Battery charger
• 1 TA-18S accelerometer transducer
• 1 transducer connection cable
• 1 magnetic base
• 1 probe
• Multilingual manual on CD-ROM
• Case for transport
• “Gettingstarted”leaetwithbasicinstructionsforuse
• 1 USB data cable
1.2 optional accessories
• Photocell (18,000 rpm) with upright and magnetic base
• 10m-long extension cable for transducers
• 10m-long extension cable for standard photocell
• CEMB N-Pro software for saving, managing and printing data.
.

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12
34 5
1.3 connections
1. sensor input
2. photocell input for velocity measurement
3. type B mini USB port for connection to PC
4. instrument reset button
5. battery charger connector
The sensors and photocell can be connected by simply inserting the connector into the relative socket, pushing it in until a
"click" is heard; make sure that the safety connection is aligned correctly, as shown in the illustration.
To extract the connector, press the terminal part (blue or yellow) and simultaneously pull the main body (grey), to release it.
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warninG!
aVoid pullinG tHe connector witH force before releasinG it as described aboVe,
otHerwise tHere would be risk of damaGinG it.
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1.4 reset switcH
In some special circumstances, CEMB customer service may advise you to reset the N200 instrument. To do this, press the
buttonlocatedonthelowerpartoftheinstrumentusingasmallobjectwitharoundedtip.Itispurposelylocatedinadifcult
to access area to prevent it from being reset unintentionally.
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warninG!
intHe eVent of an error tHat cannot be reset automatically, tHe messaGe "err" will be displayed on tHe screen
followed by tHe number identifyinG tHe error tHat occurred.
sHould tHis situation occur, tHe instrument must be reset manually by pressinG tHe reset button.
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warninG!
donot use pointed objects sucH as needles, puncHes or sucHlike to press tHe reset button as tHey could damaGe it.
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1.5 battery
The N200 instrument is provided with a built-in rechargeable lithium battery, which allows autonomy of more than eight hours
under normal operating conditions of the instrument.
The battery status is indicated by an icon in the upper right hand corner of the screen.
battery fully charged
battery partly charged
 batteryalmostat(batteryliferemainingwhenthisappearsisapprox.onehour)
 batteryat:rechargewithin5minutes
Ifthebatteryisatandtheinstrumentisnotrechargedwithin5minutesitwillswitchoff.
This would interrupt any active measurements not yet saved.
Whenthebatterychargerisconnectedthedisplaylightsupbrieyindicatingtheconnection,evenwhentheinstrumentis
switchedoff.Thebatteryiconremainsanimatedwhentheinstrumentisrecharging,progressivelyllingup.Whencharged,
the animation stops and the ‘battery fully charged’ icon is shown.
————————————————————————————————————————————————————
warninG!
wHen connectinG tHe battery cHarGer, first insert tHe connector into tHe releVant socket on tHe n200 instrument;
only pluG it into tHe power supply socket wHen tHis Has been done.
wHen recHarGed, unpluG tHe battery cHarGer from tHe power supply socket before remoVinG tHe connector from tHe instrument.
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warninG!
itis stronGly recommended to recHarGe tHe battery witH tHe instrument switcHed off: as recHarGinG is completed witHin less tHan fiVe
Hours sucH precaution preVents tHe battery cHarGer from beinG connected for an excessiVely lonG period of time (max. 12 Hours).
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warninG!
tHe litHium battery is able to witHstand tHe recHarGinG-discHarGinG cycles, eVen on adaily basis, witHout problems but it could become
damaGed if allowed to be fully discHarGed. for tHis reason it is adVisable to recHarGe tHe battery at least once eVery tHree montHs,
eVen in tHe case of extended idle period.
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N200 - Ver. 1.0 11/2016
aSthe diSplay backlighting conSuMeS the MoSt power, it SwitcheS off autoMatically after acertain period of tiMe
(Settable) haS paSSed without preSSing any key. preSSing any key (excluding will reactivate it).
————————————————————————————————————————————————————
warninG!
recHarGe tHe instrument before storinG it if you do not intend to use it for alonG period of time. intHis case, remember to recHarGe it
eVery 3 montHs: tHe internal clock also consumes power (eVen tHouGH tHe amount consumed is low), tHerefore after alonG period of
disuse it is possible tHat tHe battery will be flat.
alternatiVely, tHe battery can be disconnected before storinG tHe instrument for lonG periods of time: remember tHat in tHis case tHe
date and time will need resettinG tHe next time tHe instrument is used. intHe case of tHe second HypotHesis, to maximise tHe battery life
it sHould be fully cHarGed at least eVery 8-9 montHs.
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1.6 adjustment and calibration
Before delivering the N200 instrument to the client, CEMB laboratories subject it to a complete adjustment, calibration and
test procedure to guarantee it works correctly.
1.7 General adVice
Storeandusetheinstrumentawayfromsourcesofheatandconsiderablystrongelectromagneticelds(high-powerinver-
ters and electric motors).
Measurement precision can be invalidated by the connection cable between the transducer and the instrument, therefore
werecommendthat:
• the cable does not share the same path as the power cables;
• any power cables crossed should be overlapped perpendicularly;
• theshortestpossiblecableshouldbeused;infactoatinglinesactasactiveandpassiveaerials.
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warninG!
always pay tHe utmost attention durinG measurement operations, usinG suitable protectiVe deVices wHen possible
to safeGuard tHe operator from moVinG parts wHen not possible, always leaVe an adequate safety distance between tHem.
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2. General layout
2.1 keypad
The keyboard on the CEMB N200 instrument has a limited number of keys, enough to guarantee easy and intuitive use.
►ON / OFF button
Press this button to switch the instrument on; hold it down for at least 3 seconds to switch it off , then release the
button.
after preSSing , the inStruMent’SSerial nuMber and the verSion of the firMware inStalled will be diSplayed
briefly in the lower part of the Screen. inthe event of any probleMS, take note of thiS data before contacting
ceMb cuStoMer Service to enable uS to provide you with abetter Service.
►OK key
 Inthemainscreenitconrmstheselectionmadeandopensthecorrespondingpage.
 IntheSetupscreenitconrmsthevalueoftheparameterselected.
 IntheVibrometerandTachometerscreensitperformsdifferentfunctions:
>itconrmsvalueswhensettingacquisitionparameters
>it stops or starts the measuring process ( START / STOP THE ACQUISITION)
>when the additional functions bar is visible it is used to select the desired function
In the records screen it opens the desired function from the additional functions bar.
►BACK key
Press this key to quit the current screen and return to the previous one. It can also be pressed when setting para-
meters to end the operation without changing any values
►FUNCTION key (F)
When available, it displays the additional functions bar in the lower part of the screen.
►SET key (SET)
In the settings screen it enables the “edit” function for the parameter selected.
In the Vibrometer and Tachometer screens it enables the “edit” function for all of the measurement parameters.

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N200 - Ver. 1.0 11/2016
►directional arrows
They change the element selected, recognizable because displayed in negative (white on a
black background), or they change the value of that which is being set.
2.2 S
tart / stop tHe acquisition
In all the Measurement screens, the acquisition is started by pressing and is subsequently stopped by again pressing
.The acquisition enabled status is easy to identify by the presence (in the upper left hand corner of the screen, below
where the channel displayed is indicated) of an arrow rotating to describe a circumference.
Intherstfewmomentsafterthestartofeverymeasurement,theN200instrumentcanautomaticallydeterminethemost
suitableamplicationbasedonthesignalreceivedfromthesensors.
If the vibration is higher than the instrument's limits of operation ( APPENDIX A - TECHNICAL DATA), the channel saturation
symbol will be displayed.
2.3 specific additional functions for tHe Various paGes
Thespecicadditionalfunctionsavailableineachpagecanbedisplayedbypressingthe . key. A bar will appear in
the lower part of the screen, from which the desired function can be selected using the and arrows,andconrmed
by pressing the key.
Press to quit the bar without selecting anything.
►List of peaks
When selected, this function displays a table containing the amplitudes of the highest components of the signal, with the
corresponding frequency listed beside each one.
Uptovepeakvaluesarelistedindescendingorder,irrespectiveoftheirfrequency.Ifthesignalmeasurediscomposedof
alowernumberofsignicantcomponents,alowernumberofpeakvalueswillbedisplayed.
Press to exit this page and return to the vibrometer screen.

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►Measurement records
WiththeN200instrument,measurementstakencaneasilybesavedinarecordcontaining24positions,identiedbythe
following symbol
Thesizeofthevibrationmeasurementrecordsisoptimisedtocontainallofthemeasurementsforatypicalrealsituation:
detection in the three orthogonal directions on four supports, before and after maintenance work on machinery composed of
two elements (motor and pump, or motor and fan).
In the Vibrometer screen, press and then select the symbol , in the additional functions bar to open the cor-
responding records page.
Thesymbolintheupperpartidentiestherecord,inwhichall24positionsaremarkedwiththesymbol and a sequential
number; empty positions are marked by the symbol -----, the others contain the date and time that their contents were saved,
shownasDD/MM/YYHH:mm,where:
• DD is the day of the month (from 1 to 31)
• MM is the month of the year (from 1 to 12)
• YYarethelasttwoguresoftheyear(08for2008,09for2009,…)
• HH is the time of day (from 00 to 23)
• mm are the minutes of the hour (from 00 to 59)
The position to open can be selected using the and arrows, then the additional functions bar must be
displayedandoneofthefollowingoperationsmustbeselected:
• :savethemeasurementperformed.
The current date and time are automatically used to identify the data recorded.
.
ifthe poSition Selected iS already in uSe, before Saving the data the SyMbol aSkS the operator to confirM that
the data Should be overwritten. preSS ; the , key interruptS the Saving procedure and another poSition
can be Selected.
• :load the measurements selected
Loading data from the records allows the user to view results saved previously in a relevant screen, described
respectively in DISPLAYING MEASUREMENTS FROM THE RECORDS.
• :deletethemeasurementselected,emptyingtherelativepositionintherecords.
• :deleteallofthemeasurements,emptyingtherecordscompletely.
before deleting data froM the recordS, the SyMbol aSkS the operator to confirM the operation, which will
reSult in the data being deleted definitively. preSS the key to confirM; with , the data will not be
deleted.
the
and
keyS, which reSpectively increaSe and decreaSe the poSition Selected by 3, can be uSed to Scroll
through the recordS quickly.

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3. Home screen (menu)
AfterfullyswitchingontheN200instrument,itshowsitsHomescreen:
which,besidesshowingasetofinformation:
• manufacturer logo and name of the instrument
• the date and time
• battery state
therearetheiconsusedtoaccessthevariouspages:
Vibration measurement
Rotation velocity measurement (tachometer)
CEMB Bearing Analysis
General settings (setup)
After selecting the desired page using the and arrows, press to open it.
1. Vibrometer
>measurement of the total vibration value (Overall), together with the amplitude and frequency of the highest component
(main peak value)
>measurement of the vibration modulus and phase at the synchronous frequency at the velocity of the rotating body or
its multiples (1xRPM, 2xRPM, 3xRPM, 4xRPM and 5xRPM)
2. Tachometer
>shaft rotation velocity measurement.
3. CBA Bewaring Analysis
>Bearing analysis measurement.
4. Setup
>setting of the degree of sensitivity of sensors connected to the instrument
>setting the instrument’s general operating parameters
Thedatatransferfunction,identiedbyarelativescreen,opensautomaticallywhenaUSBcableisinsertedintotheportof
theN200instrumentandthatofaPCwhilsttherstscreenisdisplayed.
In this state the PC acts as master, while the N200 instrument acts as a simple slave, therefore pressing keys no longer has
any effect.
Once the data has been transferred to the PC ( READING DATA FROM THE N100 OR N300 INSTRUMENT), disconnect the USB
cable to return to the main panel.

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4. setup mode
All of the parameters required for correct operation of the N300 instrument can be set in the setup screen. You can scroll up
and down the list of parameters that can be set using the and arrows.
The parameter selected will be displayed in white on a black background (in negative).
To edit the value press the ,key,insertthedesiredvaluewhenrequestedtodoso,thenconrmwiththe
key.
To quit the edit function without changing the previous value press .
4.1 sensor sensitiVity
The N300 instrument can be used with various types and models of sensors, and therefore for correct measurements you
must set the exact degree of sensitivity (= number of volts per unit) of those effectively connected. Press the key, to
varythesensitivityofthesensorselected,varyingonegureatatime.
The and arrowsincreaseordecreasethegureselected(displayedinnegative)byoneunit.
By pressing and thegure on the left or on the right can be selected respectively.
Forbothpossibletypes:
• accelerometer ACC
• velocimeter VEL
• displacement DIS
twodifferentsensitivitylevelscanbeset,identiedrespectivelyby“1”and“2”.
Thereforesixdifferentsensorscanbedened:
• ACC-1:accelerometer1(powered–IEPEtype)
• ACC-2:accelerometer2(powered–IEPEtype)
• VEL-1:velocimeter1(notpowered)
• VEL-2:velocimeter2(notpowered)
• DIS-1:displacementsensor1(notpowered)
• DIS-2:displacementsensor2(notpowered)
making it possible to use the same types of sensors but with different sensitivity levels.

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Typicalsensitivityvaluesforthevarioussensorsare:
SENSOR TYPE SENSITIVITY TYPICAL VALUE
Accelerometer (ACC) mV/g 100
Velocimeter (VEL) mV/(mm/s) 21,2
Displacement (DIS) mV/µm 8
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warninG!
tHe sensitiVity of some models may differ from tHe typical Values sHown;
make sure tHat tHe sensor is set witH tHe correct Value taken from its documentation.
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4.2
date
( )
ThedatemustbeenteredintheN200instrumentusingtwoguresfortheday,twoforthemonthandtwofortheyear,inthis
order. To assist the operator, the dd/mm/yy format is displayed below the current date.
New values can be entered following the same procedure as that described above for the sensitivity of the sensor.
4.3 time (
)
TimemustbeenteredintheN200instrumentusingtwoguresforthehours(from00to23)andtwofortheminutes(from
00to59).Toassisttheoperator,thehh:mmformatisdisplayedbelowthecurrenttime.
New values can be entered following the same procedure as that described above for the sensitivity of the sensor..
4.4 units of measurement system (
)
Theunitsofmeasurementusedforacceleration,velocityandmovementvaluescanberespectively:
• g; mm/s; µm: metricunits
• g; inch/s; mils:imperialunits
After pressing the key, you can scroll through all of the possibilities using the and arrows.
4.5 display briGHtness (
)
The brightness of the display can be adjusted to provide excellent visibility in various environmental conditions, from mini-
mum (no backlighting) to maximum. This is possible using the and arrows after having enabled the “enter
values” mode by pressing .
4.6 backliGHtinG auto-off time (
)
To extend the duration of the battery before it needs recharging, the display backlighting turns off automatically after a preset
amount of time (settable from 1 to 255 seconds) has passed since the last key was pressed. Pressing any key reactivates
the backlighting.
4.7 instrument auto-off time (
)
To extend the duration of the battery before it needs recharging, the instrument turns off automatically after a preset amount
of time (settable from 5 to 60 minutes) has passed since the last key was pressed. To use the instrument again, turn it on
by pressing .

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5. Vibrometer mode
Oneofthesimplest,butatthesametimemostsignicantinformationinvibrationanalysis,istheoverallvalueoftheactual
vibration.Infact,thisisveryoftentherstparametertobeconsideredwhenevaluatingtheoperatingconditionsofamotor,
fan, pump, machine tool.
Appropriate tables allow discrimination between an optimum state and a good state, or from an allowable, tolerable, non-
permissible or even a dangerous one. ( APPENDIX B - EVALUATION CRITERIA).
In some cases it may be interesting to know the synchronous vibration modulus and phase values, that is to say correspon-
ding to the rotating body’s rotation velocity (1xRPM), or its multiples (2xRPM, 3xRPM, 4xRPM, 5xRPM).
The vibrometer function can be used to take this type of measurement easily and intuitively, saving the results in a special
record.
5.1 measurement settinGs
The settings used to measure vibration are all displayed in the Vibrometer page and can be adjusted by pressing the
key; for greater clarity all measurement results are hidden, with only adjustable parameters remaining visible. Before
changing the settings make sure that the channel displayed in the upper left hand corner is the one that you wish to change;
otherwise change it using the key.
The parameter that can be changed is displayed in negative, by pressing the and arrows you can scroll
through all of the values that can be selected. With the and arrows, you can move to the previous or next parameter.
5.1.1 SenSor type
One of the sensors for which the sensitivity has been set must be selected ( SENSOR SENSITIVITY):
• ACC-1 : type1accelerometer(powered–IEPEtype)
• ACC-2 : type2accelerometer(powered–IEPEtype)
• VEL-1 : type 1 velocimeter (not powered)
• VEL-2 : type 2 velocimeter (not powered)
• DIS-1 : type 1 displacement sensor (not powered)
• DIS-2 : type 2 displacement sensor (not powered)
When required, the N200 instrument automatically supplies power to the sensors connected.
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warninG!
toobtain asufficiently accurate measurement must be correctly specified tHe sensor effectiVely connected.
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5.1.2 MeaSureMent
Indicatesthetypeofmeasurementcarriedout:
• Overall:overallvibrationvalue
• Synchronous measurement: value of the synchronous component at the rotation velocity (1xRPM) or its multiples
(2xRPM, 3xRPM, 4xRPM, 5xRPM)
5.1.3 unitS of MeaSureMent
Selecttheunitofmeasurementinwhichthevibrationistobeexpressed;thepossibilitiesare:
• acceleration (g)
• velocity (mm/s or inch/s)
• movement (µm or mils)
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warninG!
displacement and speed measurements can be taken wHen displacement sensors are used,
HoweVer tHeir use means acceleration measurements cannot be taken.
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5.1.4 type of vibration
Like all physical sizes, vibration has a value that can vary from one moment to the next; mathematically it can be described
byafunctionoftime.Itsoverallvaluecanthereforebecalculatedinthreedifferenttypes:
• RMS (Root Mean Square):meansquarevalue
the mean value of the previously squared vibration; the most commonly used, especially for acceleration or velocity
measurements.Itisadirectindicationofthevibration’s“energy”content:inpracticeitrepresentsthepowerbroughtwith
the vibration and discharged onto the supports or bases of the vibrating structure.
• PK (Peak): peak value
the maximum value reached by the vibration in a certain period of time.
• PP (Peak-to-Peak): peak-to-peak value
the difference between the maximum value and the minimum value reached by the vibration in a certain period of time;
normally used for movement measurements.
5.1.5 unitS of frequency
• Indicateshowtodisplaythevelocityandfrequencies,andcanbechosenfrom:
• Hz:cycles(revs)persecond
• RPM:revsperminute
T
he relation 1 hz= 60 rpM clearly exiStS between the two unitS.
5.2 settinGs only Valid for oVerall measurements
5.2.1 frequency range
The overall vibration value usually originates from the sum of various contributions, caused by various phenomena, which
are therefore associated with different frequencies. Depending on the situation, you may only wish to consider those corre-
spondingtoacertainrangeoffrequenciesinoverallmeasurement:
• 1-100 Hz if the interest is limited to phenomena with low frequencies
• 2-200 Hz if the interest is limited to phenomena with relatively low frequencies
• 5-500 Hz if the phenomenon also involves average frequencies
• 10-1000 Hz to comply with the conditions set forth in the ISO 10816-1 standard (typical)

Vibration equipment division
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a coMMonly uSed practical conSideration iS to check that the MaxiMuM frequency iS Set to at leaSt 20-30 tiMeS that
of the rotation of the Shaft exaMined. thiS MeanS that even the high-frequency zone, where bearing-related
probleMS uSually occur, can be included in the SpectruM..
O
ther thingS being equal, the Selection of alow MaxiMuM frequency (leSS than 1000 hz) conSiderably lengthenS the
aMount of tiMe required for acquiSition and MeaSureMent.
5.2.2 no. of averageS
Shown next to the N symbol, it indicates the number of spectrums that must be calculated and averaged to increase the
stability of the measurement. All values between 1 and 16 are acceptable, but 4 averages are more than enough for normal
vibration measurements on rotating machines.
5.3 settinGs for syncHronous measurements only
5.3.1 SynchronouS filter width
Thisparameter,identiedforhistoricalreasonsasthesynchronouslterwidth,isdisplayednexttothesymbol and is
measured as a percentage. It indicates the resolution in frequency of the synchronous analysis, or rather the instrument’s
ability to separate contributions from the various frequencies.
Values from 1% to 100% are available.
For example, a value of 5% indicates that the contribution of all of the frequencies of the 1xRPM±5% band (which cannot be
distinguished from each other) is included in the calculation of the synchronous value.
Smallervalues(orrather,narrowerlters)producemoreaccuratemeasurements,butrequireconsiderablylongeracqui-
sitiontimes.Forexample,witha1%lterandparticularlyslowrotatingbodies(60RPM)youmustwaitforafewminutes
before completing a measurement.
Tosetthisparameteryouneedtondtherightbalancebetweenaccuracyandtime.
After setting the desired values, press toconrmthem;orpressthe key to quit the settings without changing
the existing ones.
5.4 measurement results
On the Vibrometer page the measurement results are displayed on the screen, successfully combining the need for clarity
and complete information.
5.4.1 overall MeaSureMent
1. sensor connected to the channel
2. measurement taken (Overall)
3. number of averages
4. frequency band
5. vibration value, with unit and type
6. amplitude and frequency of the vibration’s highest component. The more components the vibration is composed of, the
more the overall measurement will be greater than the amplitude of the dominating component. If the two values are very
similar, the vibration takes on an almost sinusoidal form.
The measurement can be started and stopped by pressing .

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alueS obtained thiS way can be uSed to aSSeSS the State of operation of the inStruMent, uSing, for exaMple, the
tableS and diagraMS preSent in appendix b of thiS Manual.
5.4.2 SynchronouS MeaSureMent
1. sensor connected to the channel
2. order of the harmonic measured
>1xRPM = fundamental harmonic (synchronous with the rotation velocity)
>2xRPM = second harmonic (frequency double the rotation velocity)
>3xRPM = third harmonic (frequency triple the rotation velocity)
>4xRPM = fourth harmonic (frequency four times the rotation velocity)
> 5xRPM=fthharmonic(frequencyvetimestherotationvelocity)
3. lterwidth
4. vibration modulus, with unit and type
5. vibration phase expressed in degrees (0°÷359°)
6. frequency of the harmonic measured; it coincides with the rotation velocity in the event of a 1xRPM measurement,
otherwise it is respectively double, triple, etc.
The measurement can be started and stopped by pressing .
For correct measurement ensure that the shaft velocity is stable and is read correctly by the instrument. One of the following
symbols will be displayed in the event that it is not read correctly, is unstable, or is lower than the minimum value or higher
than the maximum one ( APPENDIX A - TECHNICAL DATA):
Symbol Condition What to do
velocity value not stable over time
• check that the rotating body is not executing an accelera-
tionramp:otherwisewaittilltheendoftheramp
• check that the velocity of the rotating body does not oscil-
lateperiodically:otherwisetakeanystepspossibletosta-
bilise it
velocity signal absent, or of a value
below the minimum acceptable data
for the instrument
• checkthatthephotocellandreectingstickerarepositio-
ned correctly
• check that the photocell is NOT positioned in a point with
excessively high vibration, which would prevent the light
frombeingreectedoffthereectingsticker
• check that the velocity of the rotating body is above the
minimumvalue:otherwiseitmustbeincreased
velocity greater than the maximum
acceptable value for the instrument
• checkthatthephotocellandreectingstickerarepositio-
ned correctly (if they produce more than one impulse per
turn they generate a false high speed)
• if the velocity of the rotating body is effectively higher than
the maximum acceptable value it must be reduced