Bearing Predictor 1 – BP1 User's Manual 1
Contents
1. it pos sible to use the KCA in almost all situations even where the protec tive cover runs almost up to the motor end shield Make sure rotation doesn t stretch spring Uninsulated wire Spring or rubber band SS Picture showing KCA with uninsulated wire Hooks are magnet feet with insulated hooks or simple plastic clips clipped to the supporting structure ordinary insulated hook up wire or any string can also be used If wire is insulated then any tie point can be used insulated or not Remove insulation from wire on section that contacts shaft Connect red wire alligator clip to uninsolated part of wire and con nect BNC connector to the Bearing Predictor Ready Named after Kjell Carlsson at Pharmadule Emtunga j Anything can be used a simple screwdriver or anything conducting and with an insulated handle Rev UK2 June 2014 Bearing Predictor 1 BP1 User s Manual 10 4 Make EDM measurement and 5 Store results Now start the motor and run at the speed that you want to meas ure EDM at Press the B button under the EDM text That will start an auto matic measurement of EDM activity The display looks like this when measurements start Everything is OK probe contacts the shaft so press OK The dis play changes to Measurement starts with PPS Pulses Per Second and since this is the first measurement after start the measurement number is 1 As measureme2. so low that batteries four AA batter ies last for many months If you do not measure every week or month it is a good idea to open the battery compartment and dis connect the batteries When the Beppe is in low power stand by mode most people would say OFF you don t see anything but a blank display To start press the A key and then within three seconds the M key The splash screen below will appear for three seconds and then change to the MAIN MENU screen This is the MAIN MENU screen VAR is for measurement with variable EDM threshold EDM is for ordinary EDM measurements RCL recalls stored measurement results SET opens menus for selecting language connecting to PC checking software version clearing memory switching off and more This is to avoid involuntary turn on when transporting the instrument in its case Rev UK2 June 2014 Bearing Predictor 1 BP1 User s Manual 7 That s all there is to it The Beppe is up and running Waiting for your commands 2 Connect to machine ground The Bearing Predictor measures shaft voltage Shaft voltage is the voltage across the bearing So you need to connect to motor or machinery frame and shaft And it is important that the connection is made to the frame not to just any ground that happens to be convenient This is because of the very fast voltage edges You will get all sorts of errors if you connect to a ground bus bar
3. speeds If you need to use longer cables please contact GKE at edm gke org for directions and tips There is also the home page www gke org where more documents can be found It is being updated continuously visit regularly to stay informed Rev UK2 June 2014 Bearing Predictor 1 BP1 User s Manual 5 Getting started This section describes how to 1 Start the Bearing Predictor Connect to machine ground Connect to the motor or machine shaft Make EDM measurement Store results Recall results Switch Bearing Predictor off a R S 9 Results can be transferred to your PC To do so please read the following sections 8 Install USB driver and Beppe Manager program on your PC 9 Start Beppe Manager program connect PC to Beppe 10 Transfer data from Bearing Predictor to PC 11 Disconnect Bearing Predictor from PC The Bearing Predictor is self explanatory with operator being guided by cue texts on the display But to get the most out of the instru ment and understand all aspect of its use it is wise to study the following pages and try out the operations Do that and you can leave the operator s manual behind when you go to do the meas urements Rev UK2 June 2014 Bearing Predictor 1 BP1 User s Manual 6 1 Start the Bearing Predictor The Bearing Predictor has a low power stand by mode It closes down everything that consumes energy and blanks the display The current consumption is then
4. the center bore in the shaft This center bore can usually be contacted using an insu lated copper wire with insulation removed the last few millimeters This is usually a safe and good way of contacting the rotating shaft But sometimes there is an encoder or other transducer attached to the NDE shaft And sometimes there is no center hole in the fan guard grid So the shaft is not possible to contact One very good solution to most of these problems is to use a so called KC Attachment KCA It is simple easy risk free and reliable See description on next side There is also a risk that the motor shaft has a high voltage coupled to it This risk is very real on motors with insulated bearings and when the shaft is connected via an insulated coupling or pulley and belt Measure with volt meter or test with lamp before approach ing an unknown motor where high shaft voltage can be expected Rev UK2 June 2014 Bearing Predictor 1 BP1 User s Manual 9 The KC Attachment KCA This simple and brilliant solution to the shaft contact problem needs nothing more than an uninsulated wire and a rubber band But mostly a more sophisticated arrangement is used The idea is to let an uninsulated wire contact the shaft over a certain angle and keeping the contact force stable with the aid of a spring or a rubber band The long contact area assures a low ohm and stable electrical contact and the small dimension of the wire makes
5. verify that storage takes place and then returns to the main menu Ready for next measurement About the DELAY item in the measurement menu Rev UK2 June 2014 Bearing Predictor 1 BP1 User s Manual 12 More often than not you need three hands One to keep the probe in place one to cling to whatever scaffolding or ladder there is and one hand to press the OK button Beppe supplies that third hand for you Simply press DELAY and the measurement starts in ten seconds you will have plenty of time to put the probe in place while the dis play counts down and then starts the measurement It looks like this Measurement starts when O seconds have been reached There are two options under the SET EDM menu Stop or Continue Select Stop if you need to read PPS values before Peak values are read Select Continue if you do not want to press the M button to continue with Peak measurements after PPS measurements 6 Recall results When all measurements have been taken in that hot humid noisy dirty factory it is nice to be able to sit down in your quiet cool and clean office to analyze the results You do this by recalling the memory contents in a few easy steps Press A and then M to start the Bearing Predictor After splash screen and in MAIN MENU press C button under RCL RCL means Recall of course The Recall screen shows like this Rev UK2 June 201
6. 0 F toroid to get below 100 PPS Adding a shaft grounding device shorting brush will also help A historical note The original Bearing Predictor worked on analogue principles where the fast discharge was measured in volts per microsecond V us The device has been re designed and now works along fully digital principles which in short means that the voltage change over 100 nanoseconds 0 1 us is measured and counted The rate of change is then 200 V us from 20 V 100 V us from 10 V etcetera There are some papers where the rate of change is used instead of the now common voltage level Translate 200 V us to 20 V etcetera for comparison Rev UK2 June 2014 Bearing Predictor 1 BP1 User s Manual 25 NOTES Rev UK2 June 2014
7. 21 2008 txt You can change file name and directory at will But we keep the default name for now Doing so we may get a message that a file with that name already exists Continue if you want to overwrite or change file name if needed The memory contents of the Beppe is transferred to the PC All 40 memory places are transferred The progress bar turns green when transfer is complete Rev UK2 June 2014 Bearing Predictor 1 BP1 User s Manual 19 Get data from BEPPE Select Drive Comment E c Preload Demo tile for manual Select Directory ic 3 Program W Vie downloaded data Memory enties 40 Entries measured f Filename jedm 4 22 2008 txt kT Path IC ProgransB eppe PC managervedm U4 22 2008 bet If the View downloaded data is checked the transferred data is also shown A section of the downloaded data is shown below BEPPE EDM PROTOCOL ODate O4 27 2008 Time 10 40 59 BEPPE version 1 0 0 Serial number GEPPE o8041600 D No High Middle Low Peak Peak 1 g i 286 4 5 2 g i 14 4 3 g Ay 3279 11 10 4 g 156 3834 11 10 5 g 1 F2 BO Cd 13 11 5 g D 4 2 3 F g 6 1569 q H Z _ G 2 These data represent electrical activity on the shaft of a 2 2 kW 400 V motor fed from a PWM frequency inverter Measurements 1 2 and 6 are taken at low speeds where the oil film is rather thin so that EDM occurs at low voltages Sometimes so low that the peak voltage do
8. 4 Bearing Predictor 1 BP1 User s Manual 13 First row says that this is memory number 1 Second row says that these are peak values zero volts both positive and negative Third row allows you to step up and down in memory and also to change display between Peak and PPS results The arrow above M takes you back to the MAIN MENU yes M usually stands for Menu or More Pressing B changes the display to the PPS display First row says that these are PPS values in Memory number 1 It also shows that the High Energy Pulses Per Second PPS were zero Second row shows PPS for Medium and Low Energy Both are zero Third row as usual only that it switches to Peak There are 40 memory places available It sounds like a limitation but you can rest assured that no one has so far been able to do more than half so many measurements in one day So it should be ample Transferring data to your PC after each day s work further reduces the need for many memory places 7 Switch Bearing Predictor off There is no OFF switch on the front or top bottom panels This is for one reason Switches get damaged when hitting steel grating shafts or just about anything that it can hit in an industrial environ ment So no OFF switch Rev UK2 June 2014 Bearing Predictor 1 BP1 User s Manual 14 You switch off from the front panel If you are in the Main Menu it is easy Just press M u
9. Bearing Predictor 1 BP1 User s Manual 1 GE A 007 097 MIG TT DRIVE SYSTEM INSTRUMENTS GKE ELEKTRONIK AB GRANBERGSDAL SWEDEN Contents Safety What is it How is it done Getting started EDM limits GO NO GO Rules of thumb do they work KARMA AB VALLINGBY SWEDEN Rev UK2 June 2014 Bearing Predictor 1 BP1 User s Manual 2 Safety First You will be using the Bearing Predictor on rotating machinery and in places where it is sometimes hot cold slippery bad light conditions fumes high noise levels and other safety hazards You will be using it in mines on ships in process industry in work shops in commercial and domestic buildings In short Everywhere There will be situations that we that wrote this manual cannot always foresee But we can foresee that ignorance stress I shall only and plain carelessness will cause accidents While the Bearing Predictor hardly can cause other accidents than dropping it on your feet the machinery you work on and the envi ronment you work in can do so So please make sure that you have the proper safety training before attempting to do any measure ments in field or in the lab Many organizations have their Safe Employee or similar training sessions Do not try any measure ments before you have had that training Rev UK2 June 2014 Bearing Predictor 1 BP1 User s Manual 3 Ko 4 Now What is it The Beari
10. age break downs Every break down causes an electric discharge in the bearing and every discharge creates a tiny crater in the ball and in the races When enough craters have formed the bearing does not work any more There is a lot more to be said about this Go to Www gke org and click Downloads The downloads page is being updated continuously visit regularly for new documents and reports The discharging is very similar to Electric Discharge Machining and the Beppe detects these discharges the EDM events It classifies them in energy levels and accumulates them in counters Too many EDM events in one second mean that the bearing is at risk And more so when the EDM events occur at higher energy levels Beppe also detects potentially damaging voltage peaks that do not result in EDM events but can do so if the grease or oil gets hotter or if the shaft radial or axial load increases or if speed changes All these changes influence the oil film thickness so that a voltage peak that does not damage the bearing today may do so tomorrow For the curious EDM events are detected by checking for fast voltage changes A typical break down is from 7 15 volts and is over in less than 100 nano seconds usually in no more than 30 ns Light fastest animal in the Universe moves no more than about ten yards in 30 nanoseconds That is why a coaxial cable and a termination device are used Standard cables do not work very well at these
11. esn t get above the limit for the Low counter Rev UK2 June 2014 Bearing Predictor 1 BP1 User s Manual 20 Measurements 3 5 are at 1000 1450 RPM and 7 is taken at 650 RPM These data are typical for a small 400 V motor They are not alarming but it would definitely be better to see zeros at least in the Middle column The data in the Low column are usually not critical and there are motors running for years with many thou sands PPS at 50 V which is the level that Low is measured at Read more about typical EDM values in appendix Are these data OK It is also about time to have a look at the glossary at the end of this manual It contains many terms that are special to EDM fre quency inverters motors and bearings 11 Disconnect Bearing Predictor from PC Use BEPPE Disconnect or Ctrl F7 to disconnect El Beppe PC manager File sas Administration Help Con Disconnect Ctrl F7 vas Get data from BEPPE F9 Serial number BEPPE 08041600 Memory size 40 Memory used 7 USB communication is shut down and the Beppe display returns to Main Menu Remove USB cable from PC and Bearing Predictor Rev UK2 June 2014 Bearing Predictor 1 BP1 User s Manual 21 EDM limits GO NO GO The Bearing Predictor s main use is to find out if the EDM level in a bearing is too high or if it is safe This section of the manual is about evaluation of the PPS and Peak Volta
12. ge measurements Since EDM activity depends on many factors it is not always possible to draw valid conclusions from one single measurement Some of the factors that influ ence the EDM readings are 1 Rotational speed 2 Radial and axial bearing load 3 Bearing temperature 4 Grease presence and quality Speed is important It is generally not possible to get any valid readings at speeds below 20 30 of rated speed The reason is that the oil film has not yet de veloped so that steel steel contacts still exist in the bearings There can be no voltage and hence no dis charge and no peak voltages to detect Operation at very high speed makes the oil film thicker and therefore usually reduces discharge frequency so that false safe readings are obtained Always measure at representative operation speed Rev UK2 June 2014 Bearing Predictor 1 BP1 User s Manual 22 Forces on the bearing are important Too much radial or axial force reduces the oil film thickness Measuring an uncoupled motor where no forces act on the bear ing can produce false safe readings For reliable EDM measurements Always measure with motor coupled and with typical load Bearing temperature has a large influence on oil film thickness and EDM voltage A pump that handles fluids ranging in temperature from a few C to 80 C will show typical oil film break down voltages between 40 50 V and a few volts This does of course a
13. lso influ ence the EDM measurements Therefore Always measure when bearing has reached normal operating temperature Grease has much to say when it comes to EDM meas urement Lack of grease or bad grease makes steel steel more likely It does not only reduce L10 life it also reduces EDM activity A bearing that shows safe EDM levels when measured can after regreasing show high EDM levels Therefore Always make sure that greasing is ade quate before taking an EDM measurement When all these precautions have been taken EDM measurements are a reliable method to detect electri cal activity in bearings and also makes a fairly accu rate prediction of the individual bearing s life time pos sible Bearings that operate under varying conditions need to be checked over their entire temperature range Rev UK2 June 2014 Bearing Predictor 1 BP1 User s Manual 23 Rules of thumb do they work Yes mostly Over the years we have collected empiri cal data from many different installations and we now know that bearings with more than 10 PPS at 20 V are at risk We also know that bearings with a few PPS at 20 and 10 V are safe and that several thousand PPS at 50 V can be tolerated In tabular format PREDICTION ES lt 10 PPS lt 10 PPS RATED L10 LIFE lt 10 PPS lt 1000 PPS YEARS 100 PPS 12 VEARS 1000 PPS MONTHS The prediction is valid for four pole 1500 1800 RPM induction motor
14. n batteries go low the display gets dimmer and dimmer But memory and measurement functions are intact also when the dis play cannot be read any more That is because the display needs about 5 volts to work while the processors yes there are two of them work happily with 3 3 volts supply But you cannot use the instrument when the display can t be read So change batteries before it goes completely blank 8 Install USB driver and Beppe Manager program on your PC Warning Do not connect the USB cable to your PC before you have installed the USB driver Locate these two files on the CD COM 2 02 04 exe setup exe Run the USB driver CDM 2 02 04 later versions may exist on your CD Run setup exe It installs the Beppe Manager in a library of your choice The program icon looks like this G bepman exe GEE ELEKTRONIK AB 9 Start Beppe Manager program Double click the bepman icon Rev UK2 June 2014 Bearing Predictor 1 BP1 User s Manual 16 B Beppe PC manager File BEPPE Administration Help Status Not connected Now connect the USB cable delivered together with the Bearing Predictor Make sure that both connectors are firmly seated Prepare the Bearing Predictor for PC communication by selecting SET PC The display shows CONNECTING and waits for the PC to connect You can abort this mode by pressing any key The Beppe also aborts automatically if no connection was made in thirty sec ond
15. nder SET and get the first SETUP MENU There above A is the OFF text Press A and the display goes blank What if you are in any other menu Easy Just press M for Menu and you are there Then press SET to reach the OFF function About OFF current consumption battery low and battery change Current consumption is extremely low when the instrument has been switched off It is also quite low when active and waiting for a key to be pressed something like 250 UA It is only in some meas urement situations that current consumption increases to about 25 mA And then only for the duration of the measurement like when doing EDM and Peak measurements So batteries should last several years in normal use There are two situations where current consumption is continuous and that will empty the batteries in a few days That is when using the Variable Level EDM check and when communicating with the PC The VarLevel operation is not described in this Get Started section and is only used in certain cases The VarLevel mode is used to check actual EDM levels and is useful for detailed measurements But don t leave the instrument in VarLevel mode when you are done with the measurements When you have connected the Bearing Predictor make sure that you also disconnect Section 11 of this manual so that you do not drain the batteries Rev UK2 June 2014 Bearing Predictor 1 BP1 User s Manual 15 Whe
16. ng Predictor short name Beppe is an instrument that allows you to detect electric activity in bearings so you can apply countermeasures to avoid premature bearing damage caused by electric stray currents It does so from the very first minute after you have started that pump fan machine tool elevator printing press ship propulsion paper machine or whatever the motor is used for So you do not wait until vibration analysis or worse your ear tells you that the bearing is bad You use the Beppe to PREDICT bearing failures That s why it is called a Bearing Predictor Any bearing where Beppe says that you have excessive shaft peak voltage or where Beppe detects oil film break down is at risk And by employing standard mitigation techniques you can avoid costly future bearing failures Beppe can then be used in routine maintenance to make sure that your grounding brushes bonding straps or filters continue to do their job That is vital for the machinery s availability a failing shaft grounding device or cracked ferrite ring is like having a small hole in the ceiling the damage can go on for years and cause big problems if not detected and taken care of in time Include regular shaft volt age and EDM measurements in your maintenance schedule for bet ter availability of your machinery Rev UK2 June 2014 Bearing Predictor 1 BP1 User s Manual 4 How is it done In short By detecting and counting shaft volt
17. nts proceed the display shows the result In this case there was no EDM activity in the bearing so all energy levels High Middle Low show 0 PPS That is excellent and seldom Not always possible Most motors run at process speed then measure at that speed gt H 20 V M 10 V L 5 V The discharge energy is proportional to voltage squared H produces four times more damages than M and sixteen times more than L Rev UK2 June 2014 Bearing Predictor 1 BP1 User s Manual 11 seen in real motors The little arrow above the M button says that you can proceed with next part of the measurement Press M The Peak Value display shows Here the positive peaks were small 1V and the negative peaks are still being measured After meas urement is complete the arrow shows again Press M Now the EDM measurements for measurement position number 1 is complete The measurement results are still stored in the working memory of the Bearing Predictor but you may want to store them more permanently for later transfer to your PC So next screen is a question that allows you to either store or ignore the latest meas urement Like this If you do not want to store this measurement just press B under NO The display acknowledges your choice and returns to main menu If you on the other hand wants to store the measurements you press A under OK The display shows shortly To
18. or don t even think about it to mains ground Motors are painted And that paint is very tough So it is usually not possible to clip an alligator clip to the motor frame and get a good ground connection The ground connectors are usually placed either inside the pecker box or centrally on the motor which means far away from the shaft Actually there is usually no convenient ground connection on motors bigger than about 30 40 kW This is where the black accumulator clip shall be used It grips almost any mounting bolt s head and it has a little eye where the black alligator clip can be connected An alternative is to use one of the tiny magnets with an M3 screw on Rub the magnet against a paint free surface and connect the black alligator clip to the screw It is good practice to measure that there is a low ohm contact between M3 screw and motor frame before proceeding with any measurement Rev UK2 June 2014 Bearing Predictor 1 BP1 User s Manual 8 3 Connect to the motor or machine shaft QA 7 Danger Rotating parts A Possible high voltage Most electric motors are horizontally mounted with a shaft and coupling that connects to the driven machinery And then there is a protective cover that makes any contact with the shaft almost im possible Stopping the machine for removal of cover is not always an option So other ways have to be found One way is to use the non drive end and locate
19. s Select BEPPE Connect B Beppe PC manager Or press F7 The PC connects to Beppe PC screen and Beppe display then look like this Rev UK2 June 2014 Bearing Predictor 1 BP1 User s Manual 17 El Beppe PC manager File BEPPE Administration Help Status Connected Version 1 0 0 Serial number BEPPE 08041600 Memory size 40 Memory used 7 The PC screen verifies that connection was successful and shows firmware version serial number memory size in the connected unit and that seven memory places have been used The Beppe display also verifies that connection was successful The two arrows are used to disconnect press simultaneously if not dis connected from the PC using Ctrl F7 10 Transfer data from Bearing Predictor to PC There are two possible ways to do this either use the BEPPE Get data from BEPPE or press F9 Both do the same thing namely get data from the Beppe to a text file in the PC Rev UK2 June 2014 Bearing Predictor 1 BP1 User s Manual 18 Get data from BEPPE Select Drive Comment 3 c Preload Select Directory IES 4 Program Demo file for manual Warning File already exists and will be overwritten x xen Filename fedr 04 2120086 o oZ Path C Program Beppe PC manageredm 04 21 2008 txt M View downloaded data In both cases we get a screen saying that the file name will be edm 04
20. s in the 11 1000 kW range For higher speeds life is gener ally shorter Simple rule Less than 10 PPS H and less than 100 PPS M is OK A typical measurement on pump motors in the 100 250 kW range and running at around 1500 RPM is shown in the table on next page communication with customer in the Netherlands There the number of PPS was quite high and bearing life very short Fitting common mode filters Vacuumschmelze 250 F toroids reduced number of PPS to non critical values Rev UK2 June 2014 Bearing Predictor 1 BP1 User s Manual 24 Without common mode Filters WithCommon modeFilters H 20v mov sv v v H 20v motora xt xt St x x O yY A aA aj 1545 y 7 Motor3 3224 10748 23338 12 10 O og S a s s a 3 In this case there were four motors with very short bearing life Under Without Common mode Filters the EDM measurements were done before fitting common mode filters No measurement taken on motor number 1 Under With Common mode Filters the EDM activity was meas ured after the common mode filters had been fitted The filters re duce EDM effectively and it is only motor number 4 that still has a somewhat high PPS number at 10 V It is expected that all these motors except motor number 4 will have bearing life corresponding to their nominal L10 life If motor number four fails after MANY YEARS as the table says one will probably have to add another 25
Download Pdf Manuals
Related Search