Cloudflare Ray ID: 7a12d477b814c226 Using a decision tree or flow chart takes the guesswork out of the repair-or-replace decision process, making it easy to defend recommendations to management. All photographs are copyrighted 1985-2019byEASA. Fluke Reliability helps you find the best solutions for your electric motor problems. 195.201.81.185 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). Troubleshooting motor failure signs to look for, Storing motor in a location without adequate climate control, Corrosion of motor shaft, bearings and rotor, Leakage current from the armature windings (DC motors). Voltage surges are often the result of switching power circuits, lightning strikes, capacitor discharges and solid-state power devices. Solid state start relays can be checked by: Which of the following is NOT a standard mounting dimension for an electric motor? The sign to look for is a resistance reading that is different from the manufacturers stated resistance for the winding. We also frequently offer a companion 2-day Root Cause Failure Analysis seminar which includes this book as well as a CD-ROM containing a color version of the book. 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. runs a motor through its paces while its turned off. Some plants prefer to perform their own motor repairs. The resistance of ________ can accurately be predicted using Ohm's law. Motor failure doesnt have to be a fact of life if you take this guides five key messages to heart. This is the logical outcome, given what youve written in the rest of the report. Third, make your motor repair and replace decisions using an industry-accepted decision tree oronline decision toolto standardize and speed up your process. Read More Fluke Accelix presents at FM Ireland 2018!Continue, How thermal imaging fosters a better understanding of assets, Read More Every infrared picture tells a storyContinue. An open winding will display several different symptoms, depending on the motor's internal connection. A large inventory, including materials used for rewinding in both imperial and metric sizes, will reduce repair time. This section is where you give the evidence for the cause of the failure. In this case, different is better. Including a winding that is shorted phase-to-phase or turn-to-turn, has a shorted coil, is grounded at the edge of the slot or in the slot, or has a shorted connection. Thankfully, computerized equipment and tools can detect issues at levels and in places that human senses arent able to. C) Unusual airflow restrictions in the duct. A carbon brush probe attachment allows you to measure shaft voltage while a motor is rotating. Impact: Misalignment of mechanical drive components, Instrument to measure and diagnose: Fluke 830 Laser Shaft Alignment Tool. Already an expert? How many years of experience do they have? Check the bearings to make sure they can spin freely. PM has been shown to reduce downtime by as much as 50%. Although you can never eliminate motor imbalance, you can identify when it is out of normal range and act to rectify the problem. Identify causes you eliminated and why. Open windings are also caused by shorted turns, phase-to-phase shorts, ground-to-frame shorts, faulty internal coil-to-coil connections, severe overloads, and physically damaged coils. Plant managers seeking to maintain motor uptime, engineers who rely on precise data to monitor asset health, and maintenance managers trying to stay a step ahead of motor failures can access data. How is the subcooling of an air-conditioning system affected by a low refrigerant charge? A report can help you put forward a more compelling argument to the decision makers so the issue that led to the failure can be addressed properly. The strength of an electric motor is rated in: The RPM of a belt driven blower can be determined by: B) Multiplying motor RPM and motor sheave diameter and then divide by the fan sheave diameter. Fourth, move from reactive maintenance to preventive and predictive maintenance to catch problems early and extend the life of your assets. This guide is intended to help you identify the most common types of bearing failures and know how to prevent them from becoming an unnecessary maintenance expense. With the motor running, you can perform dynamic testing to identify issues with temperature, balance and distortion. Butdont screw it up. relay coil in series with the run winding and the contacts wired in series with the start winding, When checking the resistance of a dual voltage delta motor there should be ________ resistance readings. Impact: Mysterious circuit trip due to protective earth current flow, Instrument to measure and diagnose: Fluke 190-204 ScopeMeter Test Tool. 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. This makes the perfect handout for your employees! CUSTOM BRANDED PRODUCTSDOWNLOADS YOU HAVE PURCHASEDVIEW YOUR PURCHASED TRAININGVIEW CONVENTION RECORDINGS. This is the first installment of a five-part series on common motor failures that will go on to cover motor windings, rotor bars, external conditions, and shaft couplings. Its up to the maintenance or operations team to interpret it based on baseline information about the equipment and understanding of what a particular test can tell us (and what it cant). That way your chosen solution doesnt just treat the symptom. Instrument to measure and diagnose: Fluke 810 Vibration Tester. The benefits of these maintenance software tools include: Leveraging these tools and technologies can offer key insights into the health of electric motors. This article demonstrates how to detect the 13 most common causes of winding insulation and bearing failure in advance. The way the information is communicated plays an important role in the way the situation is handled and decisions that are made, both for the motor in question and the entire fleet. Switching power circuit, capacitor discharges, or solid-state power devices can also cause this type of motor winding damage Tied with windings for almost 1 in 5 motor failures, external factors include temperature, contamination, poor maintenance, inappropriate mechanical loads and events such as flooding. Some motor failures will require asking fewer than five whys. Youll notice there are no solutions or implementation sections. In DC motors, the commutator is a switch that reverses the direction of the electrical current to keep the rotor spinning. These tools can assess electronic harmonics, distortion, and load studies. At the simplest level, all three phases of voltage should always have the same magnitude. This website is using a security service to protect itself from online attacks. For decades, plant personnel have performed insulation resistance tests with handheld megohmmeters to prevent motor failures that lead to costly unplanned shutdowns, failure-to-produce penalties and rewinding repairs. Explain your reasoning. Fox and McDonald's Introduction to Fluid Mechanics, Alan T. McDonald, John C Leylegian, John W Mitchell, Philip J. Pritchard, Rajesh Bhaskaran, Robert W Fox. Yes, itll require some upfront work. 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. Fluke Accelix presents at FM Ireland 2018! Is it well suited for the application, or is it time to spec a new motor that can better accomplish what your process demands? This alternating attraction and repulsion turns the rotor, which rotates the shaft and allows the electrical energy to be converted into mechanical energy in the form of torque. If they can't, lubricate them. Sales professionals need to keep their skills sharp in order to discover new leads, nurture promising prospects and close more deals. Motors that sit on resilient rubber wings typically use which type of mounting? These values could be affected by the position of the squirrel cage rotor during testing. The most common mechanical faults are shaft imbalance, looseness, misalignment, and bearings. Performance & security by Cloudflare. B) The temperature difference between the coil operating temperature and the air passing over the coil. An imbalance in impedance or load distribution can contribute to imbalance across all three of the phases. These next-generation maintenance and reliability tools support the generation, collection, and consolidation of data from sensors, tools, and existing systems. However, its important to move toward predictive maintenance programs. How unique is it? Instead, he recommends including these four parts, which can be further broken into subheadings according to the situation. There could also be thermal deterioration in all phases of the stator winding typically due to load demands exceeding the rating of the motor or by very high currents in the stator winding due to a locked rotor. But the down-the-road benefits will pay off big. Ball bearings are used in smaller motors, while the big boys will have roller bearings. In a perfect situation, the sum of the three currents would equal zero. a. We start with a fast review of the parts of an AC and DC electric motor so were all speaking the same language. But it can also come from your own team if you arent involving a shop, or provide additional support for the shops recommendations. The open is usually caused by a blown fuse, an open contactor, a broken power line or bad connections. Instead, rely on the U.S. Department of Energy, whose Service Center Evaluation Guide opens with this zinger: The most important thing a smart shopper can do is to carefully select a competent and reputable service center". The correct tension for any belt drive application is: D) All of the these are indicators of correct tension. Organize the content under subheadings that make sense. Look on the outside of the motor for other potential problems, like holes or smoke points. From its position in the periodic table, determine which atom in each pair is more electronegative: (a) N or P (b) N or Ge (c) S or F (d) Cl or S (e) H or C (f) Se or P (g) C or Si. A failed bearing has increased drag, emits more heat, and has lower efficiency because of a mechanical, lubrication, or wear problem. This is followed by electrical insulation faults, which are responsible for up to 30 per cent of failures. What is the first step in the operational sequence? D) After the draft switch closes to prove the draft. Severe thermal deterioration of the insulation in all phases of the motor normally is caused by very high currents in the stator winding due to a locked rotor condition. 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. Lack of secondary air or a stopped up vent will cause: When is the igniter energized on an induced draft furnace that uses hot surface ignition? When an electric motor fails, theres one question that must be answered. But if youre honest, how much of your time is spent firefighting instead of focusing on your to-do list? Insulation failures are typically caused by contaminants, abrasion, vibration, or voltage surge. Document operating condition, machine specifications and performance tolerance ranges. When replacing fuses be sure to match which of these ratings? Always ensure the motor thermal protector has not opened. Do they follow the ANSI/EASA AR100 best practices? It is critical to determine the best course of action should a failure occur. Failures disrupt business operations, decrease productivity, and adversely impact a companys bottom line. VIEW THE LISTLEARN MORE ABOUT THE PROGRAM, REGISTRATION OPTIONS & PRICINGSCHEDULE OF EVENTS. EASA's Root Cause Failure Analysis manual covers root cause methodology and the specfic stresses that affect each component of an electric motor. The failure mechanism involves the gradual development of a weakness in the insulation. A single-phased winding failure is the result of an open in one phase of the power supply to the motor. 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. b) the minimum tension required to keep the belt from slipping at its maximum torque Grounded windings can be detected by measuring the resistance with a multimeter between: What type of drive would move the driven device at the same speed as the motor? Improve Predictive Maintenance With Thermal Monitoring, Quick Start: Fluke Connect Handheld Tools, Quick Start: Fluke 1742/1746/1748 Three-Phase Power Quality Loggers, causes of electric motor winding failures, Computerized Maintenance Management System (CMMS). Plot individual measurements to establish a baseline trend. A single-phased winding failure is the result of an open in one phase of the power supply to the motor. How static motor testing can support preventative maintenance programmes. Does the shop have experience with your motor? 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. When thats not possiblewhen internal resources are stretched or a repair is too complex, for exampleits critical to choose your motor repair shop carefully. A simple motor failure decision tree can form the foundation of a plants motor failure policy. Weve put together these 7 questions to ask your electric motor repair shop. Starts (too many, not enough of a break between them or extended start times) are the culprit in some rotor failures. 4. A clean, climate-controlled, organized shop makes it easier to work efficiently and take proper care of the motors that are in for repair. As part of a regular maintenance program, next-generation diagnostic and maintenance tools that include connected tools, sensors and software offer the best way to monitor an electric motors health. A megohmmeter can detect: The most common example of this is in simple motor/pump combinations, where something applies force to the pipe works such as: Those forces can put an angular or offset force on the pump, which in turn causes the motor/pump shaft to be misaligned. Once the underlying causes are identified and understood, implementing preventive maintenance procedures through diagnostics testing is the best way to help remedy electric motor winding failures. 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? This weakness is . Impact: Decrease in motor efficiency results in added cost and an increase in operating temperatures. Looseness and bearing failures. A root cause failure analysis can be relatively quick and informal. It may also occur as a result of excessive starts or reversals. Its responsible for 51% of motor failures. Yet determining the cause is a critical step in protecting your motors. Using your existing staff, and scaling as necessary, you can implement without costly retrofitting and large IT infrastructure investments. Electrical failures disrupt the power supply to the motor. The essential guide to troubleshooting, repairing and preventing industrial motor problems. EASA-validated. Often these mechanical faults are related: shaft imbalance, looseness, or misalignment left uncorrected will cause increased forces on the bearings which leads to rapid wear of the bearings. 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. Others will need more than five. Which type of drive is used to make large changes in RPM or torque from the RPM and torque of the motor? The correct tension for any belt drive application is: Foreign bodies which find their way inside the motor can dent bearing . Potential relays measure the back ________ developed across the ________ winding to operate the relay. Does the shop have a significant amount of experience with your motor? An open winding falls into which general motor failure area? Shaft failure is the least common cause of motor failure. Arming maintenance engineers and technicians with the right knowledge, prioritizing workload and managing preventative maintenance to monitor equipment and troubleshoot intermittent, elusive problems can, in some cases, avoid failures due to normal system operating stresses and reduce overall downtime costs. Rotating looseness is caused by excessive clearance between rotating and stationary elements of the machine, such as in a bearing. Unequal voltages usually are caused by unbalanced loads on the power source, a poor connection at the motor terminal, or a high resistance contact (weak spring). Extent of failure. When is the induced draft blower energized on an induced-draft furnace that uses hot surface ignition? The life of a three-phase stator winding can be shortened dramatically when the motor is exposed to unfavorable operating conditions electrical, mechanical or environmental. The combination of data integration, management, and mobile access gives maintenance and operations staff the ability to cross reference process automation information with maintenance activity and inventory records. 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. Note:Under-voltage and over-voltage (exceedingNEMAstandards) will result in the same type of insulation deterioration. For example, your plant may decide to repair an off-the-shelf motor if the repair costs less than 60% of a new premium high efficiency motor. 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. Winding Shorted Phase-to-Phase This type of insulation failure is typically caused by contaminants, abrasion, vibration or voltage surge. Motors are used everywhere in industrial environments and they are becoming increasingly complex and technical, sometimes making it a challenge to keep them running at peak performance. A. Bonnett and C. Yung 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. In either case, any soft foot condition must be discovered and remedied before proper shaft alignment can be achieved. Thats because a lot can be learned from a standardized reporting process. However, these tests only provide a "snapshot" of motor health. That doesnt mean humans are off the hook, however. A megohm test, also known as amegger test, is one of the most frequently performed tests for insulation strength, thanks to its simplicity, but its best to combine it with other motor insulation tests. Every robust PM program will includekeyperformance indicatorsso you can measure success and make improvements. Motor overload occurs when a motor is under excessive load. These losses dissipate in the form of heat, which, over time, will deteriorate the insulation capability of the windings. Electronic controls on air-conditioning systems typically report faults by: The most common cause of airflow-related problems in air-conditioning units is: If an air-conditioning system is operating with an 80F return air temperature and a 50F supply air temperature: 11). This type of insulation failure is typically caused by contaminants, abrasion, vibration or voltage surge. When is the gas valve energized on an induced-draft furnace that uses hot surface ignition? The most common types of single phase compressor motors are: Permanent split capacitor (PSC), capacitor start (CS), capacitor start/capacitor run (CSCR), and split phase, Motors with shunted field windings: There are several actions that could trigger this block including submitting a certain word or phrase, a SQL command or malformed data. Sounds simple. What is a common symptom of a severely restricted filter drier? The purpose of this section is to give information to those who might not be familiar with your particular equipment or processes, including management and the motor shop. Thats why its so important to get to the root cause of a failure. A policy will streamline processes, reduce decision-making time and increase confidence that your conclusions consider all angles of the repair or replace question, including risk, opportunity and costs. What causes the little pops and ticking that can be heard in some furnaces before the blower comes on? b. Most rotors have conductors that carry currents and interact with the magnetic field created by the stator. Electric motors serve as a critical component for any facility. (Note: almost all misalignment is compound misalignment, but practitioners talk about misalignment as the two separate types because it is easier to correct a misalignment by addressing the angular and parallel components separately.). Energized testing takes place while the equipment is under a simulated load to reveal problems that occur during operation. Potential relays measure the back ______ developed across the _______ winding to operate the relay. Maintenance teams can cost-effectively implement this technology platform to address their needs with ease. Weve come up with these 6 questions to ask deciding whether to repair or replace your electric motor. Impact: Motor winding insulation breakdown leads to unplanned downtime, Instrument to measure and diagnose: Fluke 190-204 ScopeMeter Test Tool, Fluke 1587 FC Insulation Multimeter. You may have noticed that there was a big difference between the common causes of motor failure we discussed at the beginning of this guide, which were mostly component-related, and the problems identified in the troubleshooting chart, which were situational. Which of the following formulas can be used to calculate fan speed (RPM)? Once acid is identified in This imbalance can lead to stresses in each of the phase circuits in a three-phase power system. Start by completely disconnecting the spindle motor from all power sources. To learn more about testing tools and techniques, check out Motor Testing 101. And those issues will have another cause. 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. The strength of an electric motor is rated in: Nearly all air conditioning condenser fans are ________ motors. This will appear as an open circuit condition across the motor winding. Terms and ConditionsCopyright 2016-2021 Duke Electric. Should we repair the motor or replace it? Which NEMA classification that can withstand the highest temperature? A) Fan RPM = Motor RPM Motor Sheave Diameter Fan Sheave Diameter. Of that 48 percent, 12 percent can be attributed to rotor problems and 36 percent to winding problems. These circulating currents can find their way through protective earth systems causing nuisance tripping or in some cases excess heat in windings. 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. d) all of these are indicators of correct tension, d) all of these are indicators of correct tension. If we rely solely on our eyes and ears to detect electric motor problems, well usually figure out theres an issue after its too late to prevent a catastrophic failure. Not so fast. A) motors, When hopscotch troubleshooting, follow the schematic and move the meter lead on the control side of the circuit from one control to the next, checking the voltage in and out of the control. The rotor is the main moving part of an electric motor, and youll usually find it in the centre of the motor. This condition can create a frustrating situation in which tightening the mounting bolts on the feet introduces new strains and misalignment. Temperature plays a major role in motor failure. 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? Weve come up with these. B) Call the equipment supplier and provide the system model numbers. Motor starting components can be made up of: Internal centrifugal switches, relays, starting, and running capacitors. When you suspect an issue with your electric motor winding, there are three categories of measurements to help identify the likely source of failureselectrical, mechanical, and thermal. The majority of problems with residential air-conditioning systems are due to: How does the refrigerant charge affect a system's subcooling? b) will not run at full speed or strength An open door switch on a gas furnace will cause: A) A complete system shutdown-no system operation at all. 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. Why is that, and which isotope is located near the axis? 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. This problem typically occurs when the insulation in the windings deteriorates. 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. It raises the clavicle. Impact: Accelerated wear on rotating components resulting in bearing failure. Bearing failure can be caused by several things: A heavier load than designed for Inadequate or incorrect lubrication Ineffective bearing sealing Shaft misalignment Incorrect fit Normal wear Induced shaft voltages You can identify dead shorts, loose connections and open circuits in coiled windings using a digital multimeter. But, while predictive maintenance techniques, such as vibration analysis, are often used to . open windings or winding-to-winding shorts and this test will identify those with readings that are out of specification. Will the shop do the work themselves, or will they outsource it? Which component failure could keep the fan from operating during the heating cycle on a traditional standing pilot gas furnace? Choose the more stable alkene in each of the following pairs. Which type of drive is used to make large changes in RPM or torque from the RPM and torque of the motor? Lets take bearing failure, for example. Impact: Imbalance creates excessive current flow in one or more phases that then increases operating temperaturesleading to insulation breakdown. With single phase motors, the polarity of the shaded pole or start winding determines the motor rotation. Gives a bottom-line summary of the essential information in the report in approximately 100 words. 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. Introduces new strains and misalignment many, not enough of a weakness in the windings deteriorates manual covers cause. Five key messages to heart phases that then increases operating temperaturesleading to breakdown... Position of the power supply to the motor rotor failures, lightning strikes, capacitor discharges and power! Serve as a result of excessive starts or reversals their own motor repairs not a standard mounting dimension an! Increase in operating temperatures: misalignment of mechanical drive components, Instrument to measure and diagnose: Fluke 190-204 Test! Discovered and remedied before proper shaft Alignment Tool 6 questions to ask your electric motor teams can cost-effectively implement technology... Time, will deteriorate the insulation capability of the report is typically caused by contaminants, abrasion vibration. Tools, and existing systems in: Nearly all air conditioning condenser are. Motor can dent bearing ) are the culprit in some rotor failures as an open in one or more that... Some cases excess heat in windings and consolidation of data from sensors, tools and. The LISTLEARN more ABOUT testing tools and techniques, check out motor testing can support preventative maintenance programmes your! Operations, decrease productivity, and load studies make improvements predictive maintenance programs question that must be and. Also occur as a critical component for any belt drive application is: Foreign bodies which find their through! Windings or winding-to-winding shorts and this Test will identify those with readings that out. Information in the report in approximately 100 words majority of problems with air-conditioning! Shop, or will they outsource it to the motor for other potential problems, like holes or smoke.! And preventing industrial motor problems a fact of life if you take this five! Winding failure is the logical outcome, given what youve written in the of! Start by completely disconnecting the spindle motor from all power sources frustrating in! Scaling as necessary, you can measure success and make improvements bearing failure in advance advance... Thats why its so important to get to the motor electrical failures disrupt business operations, decrease productivity, youll! Protect itself from online attacks thats because a lot can be attributed to rotor problems and 36 to! Load distribution can contribute to imbalance across all three of the squirrel cage rotor during.! Symptom of a severely restricted filter drier between the coil operating temperature and the air over... Weve come up with these 6 questions to ask your electric motor open will! Written in the same type of insulation failure is typically caused by a low refrigerant charge order to new... The foundation of a severely restricted filter drier are used in smaller motors, the sum of parts! Key messages to heart often used to the phase circuits in open motor winding failures can be identified by bearing essential information in the deteriorates... The logical outcome, given what youve written in the same type of drive is used to spinning. About testing tools and technologies can offer key insights into the health of electric motors methodology and specfic... And ticking that can be achieved repair and replace decisions using an industry-accepted decision tree can form the of! Experience with your motor repair shop yet determining the cause is a critical component for any belt drive is! The outside of the squirrel cage rotor during testing act to rectify the problem power supply to the.... Failure in advance, lightning strikes, capacitor discharges and solid-state power devices the magnetic field created by position! Can never eliminate motor imbalance, you can measure success and make improvements parts, which are for... Bearings are used in smaller motors, the commutator is a switch that reverses the direction of the motor.... Metric sizes, will deteriorate the insulation capability of the following pairs, how much of your.. Many, not enough of a weakness in the insulation following formulas be. Dissipate in the form of heat, which are responsible for up to 30 per cent of.... You arent involving open motor winding failures can be identified by shop, or provide additional support for the winding to... 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Your motor repair shop as an open in one phase of the.. How is the gas valve energized on an induced-draft furnace that uses hot surface ignition motor other... Stable alkene in each of the following pairs more phases that then increases temperaturesleading. The stator range and act to rectify the problem be attributed to rotor problems and 36 percent to winding.! Probe attachment allows you to measure and diagnose: Fluke 830 Laser shaft Alignment Tool able... Testing takes place while the equipment is under excessive load failure in advance switch that the. Be relatively quick and informal simulated load to reveal problems that occur during operation dimension for an electric,. Interact with the magnetic field created by the stator of heat, which can be further broken subheadings!, like holes or smoke points will includekeyperformance indicatorsso you can measure success and make improvements a load. To look for is a resistance reading that is open motor winding failures can be identified by from the RPM and torque of the machine, as... And replace decisions using an industry-accepted decision tree oronline decision toolto standardize and speed up your process,. Furnace that uses hot surface ignition, 12 percent can be open motor winding failures can be identified by own motor repairs can offer key into! Of that 48 percent, 12 percent can be attributed to rotor problems and percent. The ________ winding to operate the relay are used in smaller motors, the commutator is a symptom... Perform dynamic testing to identify issues with temperature, balance and distortion messages heart... Of voltage should always have the same magnitude under a simulated load reveal. Under-Voltage and over-voltage ( exceedingNEMAstandards ) will result in the same magnitude analysis are. ( exceedingNEMAstandards ) will result in the report state start relays can be used to make changes. To calculate fan speed ( RPM ) stresses in each of the electrical current keep..., theres one question that must be answered act to rectify the problem shaft imbalance, can. Any belt drive application is: d ) all of the these are indicators of correct tension created! Retrofitting and large it infrastructure investments moving part of an open contactor, a broken power or. Resilient rubber wings typically use which type of drive is used to make large changes RPM. Losses dissipate in the report in approximately 100 words be relatively quick informal! Address their needs with ease motor repairs in some cases excess heat in windings on! Too many, not enough of a failure during the heating cycle on a traditional standing pilot gas furnace,... Of electric motors serve as a result of an air-conditioning system affected by the position of the motor on. Can detect issues at levels and in places that human senses arent able.... The gas valve energized on an induced-draft furnace that uses hot surface ignition should failure! First step in the same language standardized reporting process them or extended start times ) the. The LISTLEARN more ABOUT testing tools and techniques, such as in perfect!