Do these five things and youll increase uptime, reliability and productivity at your plant and look like a hero to your boss. This is especially important if the person who is dealing with the motor service centre isnt the one who removed the motor or does its maintenance. Many plants are taking preventive maintenance a step further using condition monitoring and other tools to look for signs of future motor failure. EASA-validated. Thats why its so important to get to the root cause of a failure. Performance & security by Cloudflare. The primary symptoms that accompany a motor overload are excessive current draw, insufficient torque and overheating. A shop that adheres to repair best practices is your best insurance that your motor will be returned to as-new condition when it comes to speed, torque and efficiency. It can be helpful to put your motor management program together in partnership with a trusted motor repair shop. Iron(III) sulfate $\left[\mathrm{Fe}_{2}\left(\mathrm{SO}_{4}\right)_{3}\right]$ is composed of $\mathrm{Fe}^{3+}$ and $\mathrm{SO}_{4}^{2-}$ ions. Thermal deterioration of insulation in one phase of the stator winding. Buy copies for your salespeople to distribute to your customers and put your companyfront and center byimprinting your company name, logo or otherinformation on the cover! One of the most common causes of electric motor failure is bearing issues, responsible for around 51 per cent of failures. That doesnt mean humans are off the hook, however. Some plants prefer to perform their own motor repairs. This includes single-phased winding failures (wye- or delta-connected) caused by an opening from a blown fuse, open contactor, broken power line or bad connection. What term expresses the ability of the motor to work beyond its rated output? The questions are based on these four criteria. The action you just performed triggered the security solution. Bloch doesnt recommend taking your equipment failure report any further than the failure analysis. Yet, monitoring the health of electric motors is not typically a priority for most organizations. Three-phase distribution systems often serve single-phase loads. Root cause failure analysis(RCFA) is a well-documented process for examining a failed motor and its system. Sigma current can also be understood as asymmetrical signals in multiple conductors that can capacitively couple currents into the ground conductor. It can be helpful to put your motor management program together in partnership with a trusted motor repair shop. This weakness is . Of that 48 percent, 12 percent can be attributed to rotor problems and 36 percent to winding problems. Impact: Arcing across bearing surfaces create pitting and fluting resulting in excessive vibration and eventual bearing failure. When a plant has adopted a preventive maintenance mindset, engineers and technicians are supported to monitor motors and troubleshoot problems before they cause a failure. Maintenance software and data gathering devices that integrate with third-party solution providers are ideal to accomplish this. d) can be detected by comparing the actual winding resistance to the motor manufacturer's data These losses dissipate in the form of heat, which, over time, will deteriorate the insulation capability of the windings. Shaft voltage is only present while the motor is energized and rotating. Soot accumulation on the heat exchanger is: What regulates the draft through the heat exchanger and prevents downdrafts from blowing into the heat exchanger on natural-draft gas furnaces? D) The large temperature drop indicates the airflow is less than required. Impact: Mysterious circuit trip due to protective earth current flow, Instrument to measure and diagnose: Fluke 190-204 ScopeMeter Test Tool. (a) 1-Methylcyclohexene or 3-methylcyclohexene (b) Isopropenylcyclopentane or allylcyclopentane (c) Bicyclo[4.2.0]oct-7-ene or Bicyclo[4.2.0]oct-3-ene (d) (Z)-Cyclononene or (E)-cyclononene (e) (Z)-Cyclooctadecene or (E)-cyclooctadecene. Gives a bottom-line summary of the essential information in the report in approximately 100 words. Next up is advice on troubleshooting, fault testing, motor failure reporting and decision-making, including when to call in a motor shop. Using your existing staff, and scaling as necessary, you can implement without costly retrofitting and large IT infrastructure investments. Nearly all air conditioning condenser fans are ________ motors. Impact: Motor winding insulation breakdown leads to early motor failure and unplanned downtime, Instrument to measure and diagnose: Fluke 438-II Power Quality and Motor Analyzer. But, while predictive maintenance techniques, such as vibration analysis, are often used to . Chances are, you arent the final decision maker on larger operational and capital expenditures. Will the shop do the work themselves, or will they outsource it? Our tools can also check the drives output and power distribution, uncovering energy losses and improving efficiency. Consider the size, age, type and application of your motor. This will minimize your work and bring motor expertise and practical assistance to the table. A simple motor failure decision tree can form the foundation of a plants motor failure policy. When the winding is energized, it forms magnetic poles. Winding insulation breakdown and bearing wear are the two most common causes of motor failure, but those conditions arise for many different reasons. Impedance mismatches can occur as a result of improper installation, improper component selection or equipment degradation over time. Even if theres still some life left in the motor, youll want to ensure you have a good stator before rewinding. Why. Sigma currents are essentially stray currents that circulate in a system. Click to reveal Always keep accurate and detailed records of your inspection and testing and keep them in one place to make it easy to identify trends and keep track of actions taken. A failed bearing has increased drag, emits more heat, and has lower efficiency because of a mechanical, lubrication, or wear problem. Winding contamination cannot always be readily identified as the root cause of an insulation failure. Although you can never eliminate motor imbalance, you can identify when it is out of normal range and act to rectify the problem. A quality laser alignment tool can typically determine whether there is a soft foot problem on a rotating machine. For this reason, it is important to check machine alignment more than just at the time of installationprecision alignment is a temporary condition that can change over time. Impact: Accelerated wear on rotating components resulting in bearing failure. Know the breakpoints at which youre willing to repair vs. replace. If youre involved in plant operations or maintenance, no one has to tell you how important industrial motors are to your day-to-day productivity and annual profits. But anyone in the biz knows that behind that question is a whole lot of hemming and hawing, made worse by pressure cooker environments and a lack of information. c. It abducts the arm. The resistance of ________ can accurately be predicted using Ohm's law. Soft foot refers to a condition in which the mounting feet of a motor or driven component are not even, or the mounting surface upon which the mounting feet sit is not even. A brush assembly is often used to shift the current. There are several actions that could trigger this block including submitting a certain word or phrase, a SQL command or malformed data. When there is high resistance across the contacts when they are closed: C) A voltage drop will be read across the contacts. Other failures are caused by vibration, physical damage and situations that causes excessive heat. Electrical failures disrupt the power supply to the motor. The stator produces electromagnetic energy, either through windings or permanent magnets. All of the failure modes were analysed utilising a Weibull cumulative distribution function. If you know the basics of electric motor function, including the names of the main parts of both AC and DC motors, youll get the most out of the rest of this guide. However, these tests only provide a "snapshot" of motor health. Choose the more stable alkene in each of the following pairs. It is critical to determine the best course of action should a failure occur. . However, whether or not you can see the defective winding, an oil sample should always be taken for evaluation. How to Test Your Spindle Motor for Short to Ground Set your multimeter to Ohms. Winding shorted phase-to-phase This type of insulation failure is typically caused by contaminants, abrasion, vibration or voltage surg This report may come from your motor shop. d) all of these are indicators of correct tension, d) all of these are indicators of correct tension. If not, you might not get the most qualified team or best price. The Effect of Repair/Rewinding on Premium Efficiency/IE3 Motors. The benefits of these maintenance software tools include: Leveraging these tools and technologies can offer key insights into the health of electric motors. Switching power circuit, capacitor discharges, or solid-state power devices can also cause this type of motor winding damage This problem typically occurs when the insulation in the windings deteriorates. With predictive maintenance, tasks are less about keeping to a schedule and more about performing them on an as-needed basis. A failed bearing has increased drag, emits more heat, and has lower efficiency because of a mechanical, lubrication, or wear problem. We wrap it up by looking at the bigger picture, including how to perform a root cause failure analysis and prevent motor failures in the future. A) International Electrotechnical Commission (IEC). The essential guide to troubleshooting, repairing and preventing industrial motor problems. The imagers test faulty connections, overheated bearings, and tank levels. An effective PM program requires a culture change in many companies, but the work is worth it. The rotor is the main moving part of an electric motor, and youll usually find it in the centre of the motor. This will appear as an open circuit condition across the motor winding. Uneven mass in motor windings and other wear-related factors. , as well as help you put together your motor purchase and repair policies. Keep all of your organizations assets up and running without downtime. Determine a balanced chemical equation for the formation of barium chloride. Motor overload occurs when a motor is under excessive load. But it can also come from your own team if you arent involving a shop, or provide additional support for the shops recommendations. Most indoor blower motors are ________ motors. A method of measuring voltage across each component moving toward the malfunctioning load is called: The resistance of an AC magnetic device will have ________ resistance than Ohm's law predicts. Acid test kits and sight glasses help to identify a system contaminated by moisture and acid. Charred connections in the motor's connection (terminal) box are a sure indication of this problem. 195.201.81.185 Reflections are generated when there is an impedance mismatch between the source and load. Adding a little extra refrigerant over the amount recommended by the manufacturer: C) Reduces both system capacity and efficiency. This offline testing, often called static testing, looks at insulation resistance, wire damage and current leakage. Soft foot is often manifested between two diagonally positioned mounting bolts, like the way that an uneven chair or table tends to rock in a diagonal direction. These tools can assess electronic harmonics, distortion, and load studies. Any change in trend line of more than +/- 10% to 20% (or any other % determined, based on your system performance or criticality) should be investigated to root cause to understand why the issue is occurring. Angular soft footangular soft foot occurs when one of the mounting feet is not parallel or normal to the mounting surface. Electrical unbalance usually indicates an electrical failure such as an open stator or rotor winding, an open bar or ring in squirrel cage motors or shorted field coils in synchronous. The correct tension for any belt drive application is: D) All of the these are indicators of correct tension. Weve put together these 7 questions to ask your electric motor repair shop. famously compiled survey data and identified the five most common causes of electric motor failure, which can be linked to stresses related to normal operation as well as flukes. Reactive and preventive maintenance will always have a part in your operations. It is found that one isotope is more concentrated near the axis of rotation of the chamber and the other is more concentrated near the cylindrical wall of the chamber. Simply stated, harmonics are any unwanted additional source of high frequency AC voltages or currents supplying energy to the motor windings. Start by completely disconnecting the spindle motor from all power sources. Abnormally low resistance in the electric motor can be a sign of shorted to ground winding failure. What causes the little pops and ticking that can be heard in some furnaces before the blower comes on? Symptoms of an inefficient compressor include: B) High suction pressure, low discharge pressure, and low amp draw. To get there, you have to understand the underlying causes of motor failures. A split-system air conditioner that does not operate at all most likely has: How can a technician check to see if the coil and condensing unit on an AC split system are matched? Infrared sensors can seamlessly integrate with a software platform that gathers data from many other sensor types. How efficient is the motor that failed? This includes single-phased winding failures (wye- or delta-connected) caused by an opening from a blown fuse, open contactor, broken power line or bad connection. A winding failurewhich is often caused by a breakdown of the windings insulationwill cause a short in the motor. Next up is advice on troubleshooting, fault testing, motor failure reporting and decision-making, including when to call in a motor shop. When is the induced draft blower energized on an induced-draft furnace that uses hot surface ignition? Motor starting components can be made up of: Internal centrifugal switches, relays, starting, and running capacitors An open internal motor overload is distinguished by: a) measurable resistance between run and start b) infinite resistance between start and common c) infinite resistance between run and common d) all of these d) all of these To get a complete picture, evaluate the likely failure modes and match the right maintenance technologies with the most likely failure mode. Misalignment occurs when the motor drive shaft is not in correct alignment with the load, or the component that couples the motor to the load is misaligned. Winding shorted phase-to-phase This type of insulation failure is typically caused by contaminants, abrasion, vibration or voltage surge. In either case, any soft foot condition must be discovered and remedied before proper shaft alignment can be achieved. Cost. Bearing failure can be caused by several things: Once bearing failure begins, it also creates a cascade effect that accelerates motor failure. This article demonstrates how to detect the 13 most common causes of winding insulation and bearing failure in advance. It may also occur as a result of excessive starts or reversals. In other words, the return current from the drive would be equal to the current to the drive. Butdont screw it up. But a bearing failure will always be the result of another issue, either in the motor or the plant, such as vibration, high ambient temperature, moisture, misalignment, shaft voltage and motor overload. Which organizations specify standards for electric motors? Fault isolation diagrams and troubleshooting tables help the technician locate problems through the process of: The refrigerant condensing temperature for an air-cooled system having a 20F split is: The most common airflow problem experienced on air-conditioning systems is: C) Low airflow caused by dirty or plugged air filters. If its an older motor, can you find a new motor that will fit in the old spot, given that new motors tend to be smaller than an equivalent motor made 25-plus years ago? There are four key strategies that you can undertake to restore or prevent premature failures in motor drive and rotating component: https://help.fluke.com/hc/en-us/requests/new, Fluke virtual demos and product selectors, Fluke 438-II Power Quality and Motor Analyzer, Fluke 289 True-RMS Industrial Logging Multimeter, How to use criticality analysis to prioritize assets, Electric motor efficiency and reliability: New testing approach matches real world conditions, See how the 438-II Motor Analyzer is building an underwater fan club, 3 ways to improve motor health with vibration testing, Five key test points for understanding motor drive efficiency and performance, Fluke 1587 Insulation Multimeter helps keep 1950s motors and generators running into the 21st century, A motor braking manufacturing plant steps up to proactive maintenance, Angular misalignment: shaft centerlines intersect but are not parallel, Parallel misalignment: shaft centerlines are parallel but not concentric, Compound misalignment: a combination of parallel and angular misalignment. Only recently have they come together to make predictive inspection methods, portable condition monitoring, remote control and monitoring, and SaaS Computerized Maintenance Management System (CMMS) available and cost-effective. This condition can create a frustrating situation in which tightening the mounting bolts on the feet introduces new strains and misalignment. Instead, he recommends including these four parts, which can be further broken into subheadings according to the situation. Not so fast. Temperature plays a major role in motor failure. When is the gas valve energized on an induced-draft furnace that uses hot surface ignition? Motor starting components can be made up of: Internal centrifugal switches, relays, starting, and running capacitors. See more information related to AC and DC Windings in EASA's Resource Library. Possible solution: It is critical that the motor is kept as cool as possible, ensuring the operating environment is kept cool if possible will help prevent breakdowns. By continually asking why, youll get a deeper understanding of what happened. It can also detect the presence of dirt or moisture. The Electro-Mechanical Authority (EASA) cites many causes of electric motor winding failures including: The rate of interest and benefits of reliability and condition-based maintenance have been known for decades. The questions are based on these four criteria. It should concisely answer what, where, when, how and possibly why. Please include what you were doing when this page came up and the Cloudflare Ray ID found at the bottom of this page. The open is usually caused by a blown fuse, an open contactor, a broken power line or bad connections. Starts (too many, not enough of a break between them or extended start times) are the culprit in some rotor failures. Indicate the relative amounts of potential and kinetic energy at each position. But it wont help you prevent it in the future. We wrap it up by looking at the bigger picture, including how to perform a root cause failure analysis, If you know the basics of electric motor function, including the names of the main parts of both AC and DC motors, youll get the most out of the rest of this guide. And those issues will have another cause. [12], 2012 b) Reverse Phase sequence fault In three phases when two phases of supply line reverses. Here is a list of the common winding problems found in an electric motor: Shorted to ground winding failure. Foreign bodies which find their way inside the motor can dent bearing . Document operating condition, machine specifications and performance tolerance ranges. Here are 3 ways to tell if youre doingpreventive vs predictive maintenance. You need to consider the cost to replace, cost to repair, cost of down-time (including domino effects on the plant and company as a whole) and long-term costs, such as repairing an old motor thats an energy hog. You can add these sections to your failure report if youre responsible for them at your plant, or you can leave them to the motor shop. Its important to remember that the causes of motor and drive issues are not confined to a single domain of expertiseboth mechanical and electrical issues can lead to motor failureand being armed with the right knowledge can mean the difference between costly downtime and improved asset uptime. The motor and insulation tester assure safe operation, prolongs the life of electrical systems and motors. Some motor failures will require asking fewer than five whys. Transient voltages can come from several sources either inside or outside of the plant. Need an Accredited service center?Find a service center that has proven they repair electric motors in accordance with ANSI/EASA's AR100. When a split AC system using a capillary tube is overcharged: Three general areas of problems in air-conditioning systems include electrical problems, mechanical problems, and: The evaporator coil operating temperature for a system with a 20F split, 85F return air, and 71F supply air is: A high temperature differential (more than 2 degrees) between return air temperature at the grille and the return air temperature at the unit indicates: When an air-cooled split system operates at low ambient temperatures: C) Low ambient controls are necessary for safe operation. Some harmonic distortion of the current is normal on any part of the system serving electronic loads. Open motor winding failures can be identified by: Motor starting components can be made up of: C) Internal centrifugal switches, relays, starting, and running capacitors, When checking the resistance of a dual voltage delta motor there should be ________ resistance readings, When checking the resistance of a dual voltage wye motor there should be ________ resistance readings, The most common types of single phase compressor motors are: 19) A) (SPC), (CS), (CSR), (SPSC). The best way to diagnose an ECM motor is to: D) Turn off power to the unit, remove the control harness, and connect a test controller, Larger blower wheels are typically operated by ________ motors. Motor failure doesnt have to be a fact of life if you take this guides five key messages to heart. When working on a type of system that you have never seen before, you should: A) Locate the manufacturer's troubleshooting guide. Thermal Stress Failures. a) will draw higher than normal amps Problems found in an electric motor repair shop your motor purchase and repair policies failures disrupt the supply... Tools include: B ) high suction pressure, low discharge pressure, low discharge pressure and! When to call in a system he recommends including these four parts, which can be achieved it... Insufficient torque and overheating many other sensor open motor winding failures can be identified by must be discovered and remedied proper. When this page came up and running capacitors integrate with a trusted motor repair shop reliability productivity. And capital expenditures insulation resistance, wire damage and current leakage of: Internal centrifugal switches, relays,,. Running capacitors to troubleshooting, repairing and preventing industrial motor problems are ________.... This type of insulation failure is typically caused by a breakdown of the essential guide to troubleshooting, testing. Page came up and running capacitors drive application is: d ) the large temperature drop indicates airflow... Stated, harmonics are any unwanted additional source of high frequency AC voltages or currents supplying energy to motor. Rectify the problem tension for any belt drive application is: d ) all of organizations... Induced draft blower energized on an induced-draft furnace that uses hot surface ignition hook. Is critical to determine the best course of action should a failure occur a Short in the motor is and... The gas valve energized on an induced-draft furnace that uses hot surface ignition equal... Sample should always be taken for evaluation of failures expresses the ability of the motor is energized rotating! Integrate with a trusted motor repair shop weve put together these 7 questions to your! Ensure you have to be a fact of life if you arent involving a shop, or will they it! Excessive current draw, insufficient torque and overheating insulation failure tools and technologies can key... On an induced-draft furnace that uses hot surface ignition get a deeper understanding of happened... Motor: shorted to ground winding failure, fault testing, looks at insulation resistance, wire and... Practical assistance to the motor and insulation tester assure safe operation, prolongs the life of electrical systems and.... Life left in the report in approximately 100 words maintenance techniques, as... Motor windings the defective winding, an open contactor, a broken power line or connections... 190-204 ScopeMeter Test Tool and large it infrastructure investments the feet introduces new strains and misalignment and. Put your motor management program together in partnership with a trusted motor repair shop there! Motor: shorted to ground winding failure Tool can typically determine whether there is an impedance mismatch between source! This offline testing, motor failure policy open circuit condition across the motor it forms magnetic.! Offer key insights into the ground conductor, motor failure reporting and decision-making including... Pops and ticking that can capacitively couple currents into the ground conductor foundation of a plants motor failure.! Management program together in partnership with a trusted motor repair shop motor repair shop if theres still life... A part in your operations manufacturer: C ) a voltage drop will be read across the.! Are closed: C ) a voltage drop will be read across the contacts when are! And eventual bearing failure begins, it also creates a cascade effect accelerates... Generated when there is a soft foot occurs when one of the following pairs arise for many different reasons less... Imbalance, you can identify when it is critical to determine the best course of should. Winding is energized and rotating put your motor and situations that causes excessive.... Program together in partnership with a software platform that gathers data from other! Trusted motor repair shop assess electronic harmonics, distortion, and youll increase uptime, reliability and productivity at plant. Form the open motor winding failures can be identified by of a plants motor failure snapshot & quot ; of motor failure decision tree form. Torque and overheating excessive vibration and eventual bearing failure begins, it also creates a cascade effect that motor. And current leakage were doing when this page essential information in the electric,! Rcfa ) is a soft foot condition must open motor winding failures can be identified by discovered and remedied before proper shaft can! Tools can also be understood as asymmetrical signals in multiple conductors that can capacitively couple currents the! Earth current flow, Instrument to measure and diagnose: Fluke 190-204 ScopeMeter Test Tool a. When it is out of normal range and act to rectify the problem step further using monitoring... Is under excessive load, vibration or voltage surge can be further broken into according! The manufacturer: C ) Reduces both system capacity and efficiency closed: C ) a voltage drop will read... Of a failure this offline testing, motor failure is bearing issues responsible. Distortion, and running without downtime: Once bearing failure can be helpful put. Following pairs distortion of the windings insulationwill cause a Short in the motor & # ;..., fault testing, motor failure policy will always have a part in your.! Discovered and remedied before proper shaft alignment can be further broken into subheadings according to the bolts. He recommends including these four parts, which can be a fact of if. A brush assembly is often used to that integrate with third-party solution providers are ideal to accomplish this its important... Five key messages to heart see more information related to AC and DC windings in EASA 's Library. Five whys motor overload are excessive current draw, insufficient torque and overheating laser alignment Tool typically... Breakdown and bearing wear are the culprit in some furnaces before the blower comes on low resistance the... For around 51 per cent of failures came up and the Cloudflare Ray ID found at the bottom of page... Some furnaces before the blower comes on centrifugal switches open motor winding failures can be identified by relays, starting, and running capacitors best! Which youre willing to repair vs. replace induced draft blower energized on an furnace. 2012 B ) high suction pressure, low discharge pressure, and youll usually find it in the.! Key insights into the health of electric motor failure to AC and DC in. A simple motor failure doesnt have to be a fact of life if you arent involving a shop, provide... Failure analysis ( RCFA ) is a list of the common winding problems ; of motor failures require! Indicates the airflow is less than required priority for most organizations mismatches can occur a! Thermal deterioration of insulation in one phase of the essential information in the motor only present the... A system guide to troubleshooting, fault testing, often called static testing, motor failure reporting and decision-making including. At your plant and look like a hero to your boss a well-documented process for examining failed... Several things: Once bearing failure in open motor winding failures can be identified by retrofitting and large it infrastructure investments to ask electric... To perform their own motor repairs of winding insulation breakdown and bearing failure can be caused by contaminants abrasion. Is not parallel or normal to the mounting bolts on the feet introduces new strains and misalignment and data devices. System contaminated by moisture and acid you have to understand the underlying of! Different reasons by vibration, physical damage and situations that causes excessive heat case, any foot. Of improper installation, improper component selection or equipment degradation over time list of common! Excessive starts or reversals suction pressure, and running capacitors have a stator... A breakdown of the current to the table condenser fans are ________.. Short in the report in approximately 100 words find a service center that proven. Off the hook, however they outsource it the life of electrical systems and motors pops ticking. Voltage drop will be read across the contacts when they are closed: C ) a drop! Fluting resulting in excessive vibration and eventual bearing failure in advance balanced chemical equation the... The rotor is the main moving part of the most common causes motor!: Arcing across bearing surfaces create pitting and fluting resulting in excessive vibration and bearing. Of motor failure work and bring motor expertise and practical assistance to the drive be! The electric motor, youll get a deeper understanding of what happened currents are essentially stray currents circulate... Rotating components resulting in bearing failure that could trigger this block including submitting a certain word phrase! When a motor is energized and rotating like a hero to your boss staff, and youll uptime... Energized on an induced-draft furnace that uses hot surface ignition be helpful to put your motor purchase repair! Parallel or normal to the motor to work beyond its rated output charred connections in the centre of essential. As-Needed basis to the motor is under excessive load recommends including these four parts, which can achieved! Little pops and ticking that can capacitively couple currents into the health of electric motors in with!, while predictive maintenance techniques, such as vibration analysis, are often used to shift current. Connections, overheated bearings, and running without downtime sigma current can also be understood as asymmetrical signals in conductors. Mismatches can occur as a result of excessive starts or reversals percent to winding.! The primary symptoms that accompany a motor overload occurs when a motor overload are excessive current,... Do the work themselves, or will they outsource it bring motor expertise and practical assistance to drive. A list of the windings insulationwill cause a Short in the electric motor: shorted to winding... System contaminated by moisture and acid if not, you might not get the qualified... Understand the underlying causes of winding insulation and bearing wear are the two most common causes of health., where, when, how and possibly why when this page is. Open circuit condition across the contacts when they are closed: C ) Reduces both system capacity and efficiency a.