Isodis 3739en, condition monitoring and diagnostics. The main features of vibration motor is the magnet coreless dc motor are permanent, which means it will. Beginning vibration analysis connection technology center, inc. They are probability based and field testing should always be performed regardless of how sure you are of the diagnosis. Parallel causes radial forces and angular causes axial some 1x 2. This vibration reduces the expected life of the pump bearings and other components. Acdc motor repair, ranging up to 1,000 hp and weighing up to 20,000pounds. If a machinery problem exists, fft spectra provide information to help determine the source and cause of the problem and, with trending, how long until the pr oblem becomes critical. Most of them are caused by the overheating of motor. In addition, the rotary speed of the rotor is sufficiently small in comparison with the propagation speed of a bending wave. Iso 2372 10816 standards provide guidance for evaluating vibration severity in machines operating in the 10 to 200hz 600 to 12,000 rpm frequency range.
Fault detection of the electrical motors based on vibration analysis. Electric motor training course certified electricity. Common causes for electric motor failure motor failure. Vibration motors are widely used in a variety of applications including cell phones, handsets, pagers, and so on. Vibration severity chart how to use this severity chart 1 3in1 chart plots vibration measure and levels for. Page 1 of 11 the influence on torsional vibration analysis of electromagnetic effects across an induction motor air gap e. You may be tasked with solving a vibration problem, or you may be overseeing someone else and you need to understand the process. Making baseline vibration readings on electric motors youtube. Motor analysis support tool, electric machine design toolkit, of ansys maxwell, performs in full automatic an efficiency map computation and speedtorque characteristic of a pm motor and realizes significant efficiency in development time by the function of displaying an efficiency map graph. Electric motor how its madesuper electric motor manufacturing technology in china duration. Most of the electric motor failures occur at the start up.
Guidance notes on equipment condition monitoring techniques. Iso 10816 vibration severity standards iso 2372 10816 standards provide guidance for evaluating vibration severity in machines operating in the 10 to 200hz 600 to 12,000 rpm frequency range. Our repair division offers all levels of motor and pump repair, service and rewinding. Note that you may also use coast down testing to aid in determining if an induction motor vibration problem is electrical or mechanical in nature. The fundamental result of the forced harmonic analysis is the absolute vibration displacement magnitudes as in a frequencybased. Generally, the solutions have involved changes to the software in the vfd control system. Causes and control of electrical machine vibration ee.
So, what we can do is take it one step at a time and. Vibration analysis an animated introduction by mobius institute. Vibration signals were measured by piezoelectric accelerometers, acoustic by microphones and temperature data was collected by an infrared camera. Normally you can hear the brush chatter caused by this. Vibration, sound and thermal analysis as a condition. Lacey, engineering manager schaeffler uk limited 1. Our state of the art repair facility can handle large and small equipment repairs. Overview of an electric machine system with the motor shaft connected to a gearbox. Dc motor analysis a leader in electric motor testing.
Cpm and the vibration sensing technique see table below, determine how the machine should. Electric motors should be installed very carefully and should be looked after at regular intervals. The electrical drives are composed of an electric motor and its electric supply system. Dc motor fault zone analysis is a vital part of any dc motor maintenance program. We specialize in threephase ac motor repair through 1500 hp 230460 v, 23004160 v, dc motor repair through 500 hp. Monitor the vibration levels prior, during, and immediately after the power has been removed from the motor. The rotating machines concerned are electric motors and alternatorturbine combinations. We offer 24 hour emergency service for motor rewinding, machine shop service, core loss testing, laser alignment, pump repair, computerized balancing, vibration analysis. The role of vibration monitoring in predictive maintenance dr. Our electric motor testing service can easily determine if the fault is the cable or motor. Measuring, trending, alarming and analyzing fan and motor vibration will provide earlier warning of developing problems and allow replacement parts to be ordered. Skf electric motor condition monitoring emcm overview youtube.
The following pages are designed to provide typical examples of the vibration spectrums that will result from different problems a machine might experience. The induction motor is the most widely employed industrial electricdrive. Examples of these types of machines are small, directcoupled, electric motors and pumps, production motors, medium motors, generators, steam and gas. Vibration motor is a compact size coreless dc motor used to informs the users of receiving the signal by vibrating, no sound. The induction motor is the most widely employed industrial electric drive. Motor current monitoring and analysis mcsa is a straight forward tool to diagnosing problems with large inductive motors. This condition is usually caused by the wedge or wedge ring that hold the bars in place coming loose. Vibration diagnostic guide vibration diagnostic guide part 1 this guide is designed to introduce machinery maintenance workers to condition monitoring analysis methods used for detecting and analyzing machine component failures. In order to predict the vibration behaviour of any torsional. This 2day electric motor training course highlights the most important problems, principles and concepts related to the induction motor, proper specification, installation, protection and control, maintenance, testing and management of electric motors into the. Through monitoring and analyzing the vibration spectrum these specific frequencies can be detect and. Vibration monitoring is a well known technique used in condition monitoring and in this work vibration measurements were used as a reference signal for assessment of the value of acoustic and thermal measurements. Electric motor training course on design, control, protection, testing best practices.
This technique along with standard vibration analysis, voltage monitoring, and temperature monitoring provides a complete diagnostic perspective of motor health and condition. Dec 21, 2012 making baseline vibration readings on electric motors. Examples of these types of machines are small, directcoupled, electric motors and pumps, production motors, medium motors, generators, steam and gas turbines, turbocompressors, turbopumps and fans. Mar 24, 2016 overview of electric motor condition monitoring solutions from skf. Electric motor diagnostic chart cause frequency dominant plane power cut comments primary 2x 1. Onsite diagnostic services, including laser alignment and vibration analysis. Two induction motor cases were examined healthy motor case and combination of static eccentricity with soft foot case. As induction motor theory has never changed, the electromechanical forcing functions have always existed and created vibration problems. We have been serving industry and municipalities since 1952. Visual inspection and electrical testing of the armature and fields give the maintenance personnel an understanding of the condition of the motor. A vibration fft fast fourier transform spectrum is an incredibly useful tool for machinery vibration analysis.
Results are presented for vibration, acoustic and thermal analysis. Introduction as greater demands are placed on existing assets in terms of higher output or increased efficiency, the need to understand when things are starting to go wrong is becoming more important. A brief tutorial on machine vibration by victor wowk, p. Fixed speed machines such as alternators and synchronous motors lend themselves to relatively simple analysis and problem solution. If the machine is variable speed, look for peaks in the spectrum that ar e close to the. Each type has unique operating characteristics and applications. Noise and vibration control for mechanical equipment, manual tm58054afm 8837navfac dm3. Janelle hammes electric motor and repair, inc west columbia, sc originally from rockford, il in the motor business for 2 years. Noise and vibration analysis of elevator traction machine. About the vibration guys in an effort to consolidate and organize our businesses, condition monitoring solutions, inc. Fault detection of the electrical motors based on vibration. How basic principles of vibration analysis might be applied in a typical inplant situation can be illustrated with a pump and motor unit that shows high vertical frequencies at one end of the motor and high axial readings at the other.
Installed electric motors rms vibration velocity a recently commissioned motor installation b unlimited satisfactory long time operation. Identifying the vibration problems that can occur in inductionmotor drives have an added complexity due to the rotating magneticfields in the machine. The vibration pattern can tell us if the machine is out of balance or out of alignment. Identifying the vibration problems that can occur in induction motor drives have an added complexity due to the rotating magneticfields in the machine. The vibration analysis is one of the most important tests for understanding what is happening in a machine. These operational forces cause forced vibration and may originate from the rotating parts or operating conditions flow quantity, pressures, speed and arrangement. Therefore, the influence of the rotation of the rotor is not considered in the vibration and acoustic analyses. Excessive vibration can cause damage to the machine or reduce its lifetime, as well as damage to other items. Application notes vibration diagnostics for industrial. There are also other factors which greatly affect the performance of electric motors such as low resistance, dirt, moisture, overcurrent and vibrations. This suggests a combination of problems, including either misalignment or a problem with the sole plate or base. Electric motors and drives in torsional vibration analysis. The electric motor training course course will mostly relate to the squirrel cage induction motor however, the wound rotor, synchronous motors and permanent magnet motors will be briefly discussed. The limit values for the vibration severity values are defined by iso 108161 depending on motor classes.
Sometimes the vibrations are seen in accelerometer readings, but more consistently the vibrations are torsional. A good routine vibration program using a portable data collector, or permanent online vibration monitoring, will become the foundation of any predictive maintenance initiative. Electric motor training course certified electricity forum. Common causes for electric motor failure motor failure analysis. This document was created by field experienced skf application engineers using measurements obtained with skf. In fact, some of the most complete and best references on vibra tion in induction motors were written 30 to 40 years ago. Isodis 3739en, condition monitoring and diagnostics of. These characteristics enable the operator to perform a wide variety of tasks.
Spectrum interpretation the following pages are designed to provide typical examples of the vibration spectrums that will result from different problems a machine might experience. This technique, known as motor current signature analysis or mcsa, seeks to apply much of the long experience in vibration signature. The limits apply to a motor mounted on a seismic mass, and uncoupled or coupled to a piece of equipment in a way that eliminates any vibration in the driven equipment. Thus analysis cannot always be limited to the electric drives but have to be extended over the whole electric drive from the shaftend to the electric grid including the optional frequency converter.
Mar 14, 2019 our electric motor testing service can easily determine if the fault is the cable or motor. Spectral content of current probe signal depends on the motor and motor speed. Motor electrical fluting using vibration analysis to detect. Electric motor noise sound radiation in electric motors is. Each type of fault, electrical faults or mechanical faults, produces a vibration whit a specific frequency. This paper presents a comparison of different measurement techniques for condition monitoring of electric motors. More stringent specifications regarding motor vibration call for maximum velocity levels of 0. The role of vibration monitoring in predictive maintenance. Making baseline vibration readings on electric motors. The purpose of this tutorial is to provide sufficient knowledge to understand machine vibration diagnosis. This data was then downloaded to emonitor odyssey vibration software for analysis. Abstract recently a technique for monitoring and diagnosing mechanical problems, associated with rotating machines driven by electric motors, has been proposed and is now being offered by several commercial suppliers. A basic understanding of the principles involved, together with a simple troubleshooting guide and the right analysis.
Vibration analysis an animated introduction by mobius institute duration. This paper presents briefly some electrical and mechanical faults in induction motors and how these faults influence the motor vibration. The motors shaft torque produced is the performance indicator for the motor. The level of vibration and the pattern of the vibration tell us something about the internal condition of the rotating component. Overview of electric motor condition monitoring solutions from skf. Implementing a predictive maintenance program takes a pm program to the next level. If the vibration ceases or sharply declines almost immediately, then the problem typically.
1485 165 1267 960 801 700 398 1545 1373 740 1013 926 1347 1192 942 902 856 406 1261 301 707 85 1293 925 636 702 1324 845 704 590 223 477 142 617 332 695 13 1183 207 990 815 848 556 514 534