El motor eléctrico es un componente clave en el mundo de la industria y el transporte. La falla de un motor eléctrico puede tener un impacto significativo en los costos de mantenimiento y las ganancias de una empresa. Es por eso que, durante muchos años, muchos usuarios de motores eléctricos han estado tratando de mejorar el rendimiento de su sistema de accionamiento adoptando una estrategia de mantenimiento orientada a la predicción de fallas.
This paper presents current methods of electrical test and trend analysis of the operational health of electric motors in the context of successful predictive maintenance programs. The benefits and features of these various types of test equipment and motor testing methodologies are conveyed in the context of motor/machine “systems”, which accounts for conditions that can impact the health of a motor, but can be external to the motor itself. This paper outlines the concepts of static motor testing, or testing on a motor that is not running, as well as dynamic motor monitoring, which involves performing analysis on motors while they are in service, or operating within their application environment. It also covers an emerging type of online dynamic monitoring involving a permanently-installed networked motor analyzer that enables maintenance professionals to monitor motor system conditions from any web-accessible computer.
Instantaneous Torque as a Predictive Maintenance Tool for Variable Frequency Drives and Line Operated Motors31 Mayo 2019
Technological advances in on-line testing of motors, diagnostics and motor monitoring have increased substantially over the past few years. Voltage and current signature analyses have improved the quality of predictive maintenance (PdM) compared to what RMS current and voltage measurements or power-factor readings have been able to achieve. Signature analysis has emerged from the laboratory stage to become the foundation for modern instrumentation in mainstream industrial maintenance programs. The most advanced method of current signature analysis is torque signal analysis due to the fact it offers multiple advantages. One is the instantaneous torque signature, gained from current and voltage signatures. It
is inherently demodulated, and delivers a very clear signal independent of the line frequency (either 60Hz, or variable in VFD applications). In addition to demodulation, it delivers the clearest mechanical information available on the motor system, since torque production is the primary if not sole reason for the motor’s existence. Both motor and load failures can result in costly outages or reduced production for weeks at a time in a plant environment. The cost of such failures can easily run into millions of dollars. This paper presents three case studies where modern instrumentation averted downtime or reduced output and failure. One case study is based on findings of a coal-fired power plant, the second case study presents findings of a Lignite powered plant, and the third case study involves troubleshooting a VFD application in a sawmill.
Locomotive Motor Testing - Advanced solutions for detection and correction of locomotive traction motor problems31 Mayo 2019
Traction motor failures can be expensive. The costs of unplanned downtime and motor repair or replacement can be extreme, even to the point of damaging relationships with customers, including loss of business. Motor failures can also precipitate failures in other parts of a locomotive, such as the phase module drives for AC traction motors. Megger’s Baker Instruments product family includes AC and DC traction motor test solutions that completely evaluate the condition of the motor to deliver the high reliability and reduced costs necessary to stay competitive.
My goal is that this book will clarify a handful of the key points that are at the heart of most questions about infrared windows—their use and limitations.
The use of infrared (IR) inspection windows in industrial applications has grown exponentially over the past five years. Much of the recent acceptance has coincided with the increase in the level of awareness regarding electrical safety and risk reduction. Organizations such as OSHA, NFPA, CSA, IEEE, ANSI and NETA have been at the vanguard of this movement.
Electrical Ultrasound Inspection is one of the most unique applications as it is not dependent on decibel levels as much as the patterns the anomaly produces. However,limited approach restrictions can make it difficult to get the truest form of the Incident Sound Wave for pattern identification.
Over the years rotor bar problems have been a diagnostic challenge for motor maintenance professionals. Now with current signature, spectral torque analysis and automated computer diagnostic software, defining rotor health problems has been made fairly simple. However, problems arise when professionals Do not understand the underlying principles of the whats, whys and hows of dynamic rotor testing. Individuals need to be able to answer the following questions. How can an instrument 100 - 1,000 feet or more away from the motor provide information about the condition of the rotor? What are the effects going on within the motor to produce the peaks and ripples that we see? What defines the frequencies of the peaks and causes the amplitude to increase as the rotor bars break? And finally, how do we interpret those signals to make proactive decisions about motor repair scheduling?
In this article, we will present the following:
- A conceptual explanation of rotor construction and operation
- An explanation of the effect of a broken rotor bar on this operation
- A review of several techniques for rotor condition analysis
- An explanation of the calculations and where to find the faults frequencies in the
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