Based on the results of the computer analysis, an alternate coupling was selected to detune the TNF away from the 1× electrical frequency of the VFD. I've read that motor failure can occur as a result of too much distance between the VFD and the load. It begins with an introduction to variable frequency drives, explains briefly their major components, how they work, and what electrical frequencies (harmonics) are usually introduced when a VFD is employed. Wiring a VFD to control single phase motor speeds, Difference between 50Hz and 60Hz frequency, Impact of 60Hz (50Hz) motor being used on 50Hz (60Hz) power supply. failure, check power and cabling to rack and rack itself. Variable frequency drive main circuit failure analysis. troubleshooting 12-9 Therefore the process audit for field failure analysis is based on the composition of the questionnaire, the assessment logic and the … Sr. Single-phase input voltage on a VFD with 3-phase input is common in many automation applications. Failure rates vary widely depending on many factors, but evidence suggests that a significant portion of failures occur only 3 to 12 months after system startup. 10-25-2013, 01:50 PM #10. borne2fly. Check the VFD for contamination of dust, moisture, or other airborne particles that may be electrically conductive. 5 basic facts about VFDs to help electrical engineers and operators understand the limitations and capabilities of VFDs. The author finishes the paper with two case histories where VFD drives played a major role in the vibration problems … My question is could the VFD control been repaired or given the fact that it was in a wet environment be an indicator that the damage was too far gone to attempt repair? In some cases VFDs can disturb each other such, that other can fail because of disturbance or noise from another VFD. Failure analysis is the process of collecting and analyzing data to determine the cause of a failure, often with the goal of determining corrective actions or liability. Like Reply. Preventing faults and failures starts by right-sizing the VFD for the machine task. VFD Testing and Analysis Note 0301 APPLICATION NOTE Description Motors powered by variable fre-quency (VFD) or variable speed (VSD) drives require additional testing and analysis to ensure the high voltage stresses are not weak-ening the motor’s insulation sys-tem or the drive components. Can I run a 50Hz motor on 60Hz power supply? Write a Comment. Often the person reporting the condition has limited technical expertise and this person is reporting what they see, hear or even smell. replace systemwide failure, check words 173 and 178. l/o processor, and all cabling. 4. cooling fan failure … I. Contamination is a preventable cause of VFD failure. Transistor frequency inverter has the following disadvantages: easy trip, difficult re-start, poor overload capacity. Failures in VFDs: 1. line reactors failure or no line reactors added when needed 2. excessive harmonics and tracking, such as leakage current/voltage due moisture & dust build up, and failure to balance harmonics. Most of these things have covered in earlier comments already very well. This … Maybe my memories from past are golden but, it appears like VFDs use to be more robust, what comes to contamination like dust etc. VFD failure analysis determines the root cause of malfunctions on varying motor controllers. Identifying a fix may be simple or reveal a complex problem, which is why fault and failure prevention is always the best strategy. As the rapid development of IGBT and CPU, the inverter drive integrates perfect self-diagnosis and fault prevention features, improve the reliability greatly. A second phenomenon caused by the VFD has been responsible for accelerated wear, minute arcing across the bearing lubricant, “fluting” of the bearings, and eventual bearing failures in many VFD-driven motors. failure analysis focuses on the specific requirements of the field failure analysis processes. failures. Frequency inverter failure analysis. Modern VFDs are designed to minimize this nonlinearity by providing multipulse (12-, 18-, and 24-pulse) line converters, active front-end converters, or passive harmonic filters and line reactors … Second, and just as important, make … but there can be also logical explanation. These are the most common causes for failures what I have witnessed over the years working with variable frequency drives. Thank you for your insight on this problem of VFD failure. I was recently asked to do a "root cause analysis" for why one failed, and it's honestly quite beyond my capabilities. To prevent premature winding failure, review the VFD manufacturer’s recommendations for proper distances. A coupling with rubber blocks in compression (Figure 6) generally has a lower torsional stiffness than a steel … Read this case study how harmonic filter for VFD solved the problem including an arc flash incident whose root cause detailed in another webpage "harmonic filter powerful with super … Variable frequency drive includes main circuit, power circuit, IPM drive and protection circuits, cooling fan and other several parts. August 4, 2020 hpenrose@motordocllc.com Archive, Motor Diagnostics, Motor Management, Motor Repair, Reliability, Uncategorized, Variable Frequency Drive. For example, on a 220V line, if the average voltage fluctuates by about 2% (up to 228V), then the threshold for DBR should be set at 230V to make sure that DBRs are not triggered during normal operation. can be a big problem, if environment issues are not taken care of. Vibration Acquisition Criteria Calculator; Precision Maintenance Missing: Fan Shaft Bearings; Pump Flow issue detected through PeakVue; Slow speed bearing defect detected though vibration analysis; Failure mode ISO 15243: 5.4.2 Subsurface initiated fatigue; Pump poor foundations You must be logged in to post a comment. 3.2 Symptoms Failures: Several motor shaft failures in the stub shaft area have occurred, caused by torsional View Profile View Forum … The analysis through the current signature is a non-invasive method and can be embedded in the VFD, what is a great advantage. Many cases voltage spikes have been root cause of failures. Failure to meet the required temperature specifications can lead to premature VFD failure because numerous power components rely on adequate cooling for proper operation. Coupling failures occurred when the operation of the CTs fans' motors was at VFD mode. Cable length in and out of VFD. I have not experienced harmonics to be cause of failure, but poor groundings and other related type interference have been cause in many cases. Syed Peeran: By its nature, the VFD is a nonlinear load in the electrical system in the sense that it draws a nonsinusoidal current even if the applied voltage is perfectly sinusoidal. In this paper, we have analyzed the electrical and non-electrical causes of VFD failures based on a case study of a typical medium voltage VFD pumping station. Variable Frequency Drive (VFD) Failure Mode Effects Analysis (FMEA). Engineer I was recently asked to do a "root cause analysis" for why one failed, and it's honestly quite beyond my capabilities. Applied Technical Services’ knowledgeable engineers and technicians are capable of testing VFDs for electrical, chemical, mechanical, and thermal failures of modes. by Phil Langhorst 0 Comments VFD Management variable frequency drive testing / VFD failure analysis / VFD testing. Troubleshooting a VFD Fault Instantaneous Trip Including Bypass. A VFD’s electronic overload protection function estimates the motor overload level based on output current, output frequency, thermal motor characteristics, and time. All rights reserved. One VFD shared between the two motors, used as a soft start for the first motor which is switched to “across the line”, and then the second unit is started and run on the VFD. Tracking or arcing marks across components or circuit board traces indicate evidence of contamination failures. It is observed that the fault motor data sheet and healthy motor … You may try AMTECH ELECTRONICS VFD where there is absolutely zero failure. CSV Display Table From the analysis, failure effects from gate unit supply is very severe as this would result in uncontrolled voltage and frequency from the inverter and consequently resulting in degraded operations of … While this paper focuses on VFDs as a source of harmonics, it is important to note that VFDs are not the only source of harmonics in a system. replace fauln component. VFD itself is a big harmonic source, causing problems to other electronic devices and electric circuits. Preventing faults and failures starts by right-sizing the VFD for the machine task. In the development of the assessment standards, the target was to use the existing methodology in order to prevent any separate or additional ap-proach. ž™�¸uˆ\‰Bô-ˆC§›ÓÊlà¸àKÔÙÄ92¦ãm‹`á½bÿìSîÜšš…;ÆĞi5qæ~› l¦Ê:V|—j­ÑbÜ�¼œ�©šÄEú2°ö9s4µ4Út"é. replace faulty component. The structure is mostly unitized or modular. VFD Fault / Trip Be reassured: The VFD is protecting itself and the equipment. Variable Frequency Drives (VFDs) present unique challenges as both a source of PQ problems as well as being sensitive to incoming voltage quality. This paper presents a pair of VFD applications, problems associated with those applications, and diagnoses from the use of modern field instrumentation. VFD Harmonic When VFD drive is sizeable or many, the excessive heat and power surge due to VFD harmonic generated high waveform distortion causes drive failure and unwanted tripping. Therefore, it is imperative that this fan system have high reliability. VFD Motor Fault Analysis & Monitoring Remember We are effectively monitoring or troubleshooting a motor (with some added characteristics) There is no reason to make it harder than it really is. Components typically included in a VFD have failure rates measured in failures per billion hours. This measurement is called FIT (Failures In Time) rate, and each component or assembly is assigned such a number by its manufacturer. The structure is mostly unitized or modular. The longer the distance, the greater the voltage spikes from the VFD. Finally, … If ratings are exceeded, a larger 3-phase drive … Environment, is there excessive humidity, dust etc. Incorrect or unreasonable setting will cause the VFD malfunction and failure easily, or can't meet anticipated operation effect. Every engineer has good points about variable frequency drive (VFD) failure reasons. Of course it is always difficult to say afterwards the real reason of failure, without any facts, like measured data. I've seen VFD development for quite long period (more than 20 years). Part analysis finished6 Specific inspection test plan with indication of failure conditions5a according to known failure modes Customer documentation (dealer diagnostics, OEM/Tier1 pre-analysis)5b Agreed I.O./N.I.O. The data sheet used to training and to validate the Artificial Neural Network is obtained using a test bench that allows to apply different levels of inter turn short-circuits in the machine. This application note is designed to give a quick review of the tech-niques for testing and analyzing VFD’s and VFD driven motor data using the MCEMAX. Figure 1: ID fan and Motor. All power transfers and system outages work must occur during non-Embassy working hours. Modify GoHz Single Phase 240v Converter to Split Phase 120v/240v, 3 Phase Motor Running on Single Phase Power Supply, GoHz 30-60kVA 3-phase Frequency Converter Troubleshooting. ATS can perform VFD failure analysis during the research and development stage, as well as for existing product lines that … 3. terminal bolts not tighten to specs. The drive manufacturer did not supply the motors. The shorter the distance the better chance there will be less voltage spiking during operation. Voltage spike damages appear to be quite common reason for failures. Some of the phenomenons occur more frequently and some are rarer. The VFD needs to set the voltage threshold at which DBR should be enabled. Using variable frequency drive-driven motor, Kowalski and Wolkiewicz analyze the spectrum of instantaneous Park power and torque signals to diagnosis early SWITSC and broken rotor bars. blog.acsindustrial.com/.../top-4-reasons-for-vfd-failure-and-how-to-prevent-them A thorough investigation on the VFDs panels showed that after a successful operation of VFDs at the site, there was no set-point input signal coming from the CTs' outlet water … The VFD controlling our air compressor failed after only 10 years due to it being outside in the damp rainy Florida weather with dust and moisture I guess I should be surprised it lasted that long. failures in the field due to variations from part to part and field loading conditions. Variable frequency drive includes main circuit, power circuit, IPM drive and protection circuits, cooling fan and other several parts. Jul 24, 2011 #7 > There are other VFDs which are more reliable where IGBT failure is almost nil. Catching VFD Failures Read our methods for analyzing recorded Variable Frequency Drive data to catch VFD failures. The motor speed is controlled by a low voltage variable frequency drive (VFD) from 0 to 1200 RPM. A vibration analysis program case study utilising SPM HD Enveloping. Single-phase input voltage on a VFD with 3-phase input is common in many automation applications. This value should be set after careful analysis of the RMS input voltage. … Catching VFD Failures Read our methods for analyzing recorded Variable Frequency Drive data to catch VFD failures. VFD Fundamentals & Troubleshooting 1199--FFeebb--20102010 13 Aberdeen Way Elgin, SC 29045 Cell (803) 427-0791 By: Timothy S. Irwin, P.E. failure analysis can save money, lives, and resources … Some of these parameters are e.g. A new inline ventilation motor operating on a VFD with bypass tripped on startup with the VFD and instantaneously tripped when tested … Properly derate VFDs. So, what we can do is take it one step at a time and eliminate potential issues one at a time And never forget, Murphy’s Laws on Technology are in full effect: “Logic is a … 1) Modify GoHz Single Phase 240v Converter to Split Phase 120v/240v, 2) 3 Phase Motor Running on Single Phase Power Supply, 4) GoHz 30-60kVA 3-phase Frequency Converter Troubleshooting. The phenomenon is due to electrostatic induction of a high-frequency voltage between the shaft and the bearing race, causing the film of lubricant to break down … The failure of the flexible disc coupling consisted of … A frequent complaint with a troublesome VFD is the controller taking the drive off line due to unbalanced current draw. Sorry for the extreme necro post, but I was curious if anybody has more information on reasons for failure in a VFD. i have a one kaeser compressor with SFC which is new. Did I mention the failed drive had already been disposed of? Introduction The focus of plant … In some case it might be better to use soft starter than use VFD. If contamination is excessive, the VFD must be isolated from the … Other increasing problems with VFD are all kind of disturbances and interference. For a new VFD design, Cancel reply. Your article is informative and succinct, both a plus. Type of Interference depends also complexity of application and electric grid where VFD is used. They are not typically reporting the “problem.” VFD White Paper. • An alternative approach to avoid failures is to monitor IGBT health individually under operation by using a data-driven method to analyze the operating data and detect for faulty conditions before failure … quality analysis and electrical troubleshooting to identify the cause of an intermittent failure of installed Variable Frequency Drives (VFD) located at the American Embassy in Suva, Fiji. So dust, moisture etc. The analysis through the current signature is a non-invasive method and can be embedded in the VFD, what is a great advantage. A critical analysis of IGBT geometries, with the intention of mitigating undesirable destruction caused by fault scenarios of an adverse nature Conference Paper Jun 2003 6) Wiring a VFD to control single phase motor speeds, 7) Difference between 50Hz and 60Hz frequency, 8) Impact of 60Hz (50Hz) motor being used on 50Hz (60Hz) power supply. A poke at NFG bits of industrial lego. You may try AMTECH ELECTRONICS VFD where there is absolutely zero failure. dropwide failure procedure check power and supply, 5 l/o interface cabling i into and within the drop, an i racks. It died of natural causes. Thus VFD is suitable for wide range of applications, some parameters should be examined before installing VFD. When the VFD detects a motor overload a fault is triggered and the VFD output shuts off to protect the motor from thermal failure. B. bob peterson. Any unscheduled downtime would be costly and could quickly outweigh the energy savings from using the VFD instead of inlet dampers. This is a one-time service visit. quency (VFD) or variable speed (VSD) drives require additional testing and analysis to ensure the high voltage stresses are not weak-ening the motor’s insulation sys-tem or the drive components. Motor, is it suitable for VFD use. The tendency for VFD drives to excite system natural frequencies and cause resonance problems is mentioned. No problem was detected at normal mode, with dual speed operation through the BMS control. The sizing of VFD is important. Copyright © 2021 GoHz.com. Also the application and demands of application should be studied carefully. Bidders are asked to schedule their system testing to occur within … Buying a VFD on GoHz, 1hp VFD, 2hp VFD, 3hp VFD... Why does a VFD fails while we switch off the mains supply abd switch on again ? According to Bloch and Geitner, machinery failures reveal a reaction chain of cause and effect… usually a deficiency commonly referred to as the symptom…”. Variable Frequency Drives (VFDs) present unique challenges as both a source of PQ problems as well as being sensitive to incoming voltage quality. But what about the VFD itself? A rule of thumb is less than 150 feet. Depending on the horsepower and voltage rating, drives can accept single-phase input voltage without derating the output current. Paresh . We have several hundred AB Flex4's in my plant, and can't seem to keep them going to save our life. The advantages of using a VFD far outweigh the negative effects of harmonics, but it is important to be aware of harmonics, the potential problems they can cause, and the solutions that are available to mitigate those harmonics. 5) Can I run a 50Hz motor on 60Hz power supply? For example, a power diode usually has a statistical failure rate of 80 failures per billion hours, or 80×10-9 hours. As the size of VFD is getting smaller and smaller the gap between components are also getting smaller, and therefore all kinds of particles within VFD can cause damage. The complexity of the symptoms exceeds commonly used root mean square (RMS) handheld instrumentation, many of which can’t even discern symptoms, never mind root causes. In other words, the trigger …