Improving Electrical Reliability by Implementing Motor Circuit Analysis

When you want to determine the health of your motor, Motor Circuit Analysis (MCA™) is a preferred choice in any industry. This deenergized motor testing method allows you to gauge the entire health of your motor, transformer, generator, and other coil-based equipment in just a few minutes. MCA’s thoroughness helps you determine a motor system’s electrical health and increase your equipment’s electrical reliability.

What Is MCA?

Motor Circuit Analysis is an impedance based measurement technology that injects a Non-destructive low voltage AC sinusoidal signal through the motor winding system that exercises the entire motor insulation system to identify any unbalances in the windings that would indicate either a current or potential motor fault. In a perfectly healthy electric motor all three phases will be identical to each other meaning all measurements acquired will also be identical. A deviation of measurements between phases signifies a developing or current fault.

MCA allows the user to quickly analyze and identify the following motor faults:

  • Ground Faults – Measure the resistance between motor’s winding system and the motor frame (ground) to determine if the motor is safe to run. This value is typically measured in Megaohms (Mohms).
  • Rotor Faults – Rotor faults are determined my measuring the impedance values of all three windings as the rotor rotates in the magnetic field of the stator. Typical rotor faults are broken or fractured rotor bars and casting voids that develop during rotor manufacturing. These faults are typically not seen by eye so they will go unseen until catastrophic failure occurs unless proper testing strategies are utilized.
  • Internal Winding Shorts – Motor Circuit Analysis is capable of determining early stage turn to turn, coil to coil, and phase to phase internal winding shorts. Being able to determine these faults is what separates Motor Circuit Analysis from conventional motor testing practices. These faults develop as slight changes to the chemical makeup of the winding insulation material which means standard resistance readings will not detect these changes until a direct short between two conductors is made and a catastrophic failure occurs.

You can initiate MCA directly from the motor or at the Motor Control Center (MCC). By testing from the MCC, you can evaluate the entire motor system such as the motor starter or drive, motor cables and connections between the motor and test point. This testing method stands out from the competition, as no other motor testing technology has these capabilities and because MCA injects a low voltage signal into the motor circuit there is no need to disconnect a Variable Frequency Drive (VFD). MCA’s in-depth testing helps you easily spot errors and quickly take action to increase electrical reliability.

How Does MCA Work and Increase Electrical Reliability?

How Does MCA Work and Increase Electrical Reliability?

Test Value Static

One of the main elements of MCA solutions is the Test Value Static (TVS), which helps you maintain electrical reliability in your motor. A motor’s TVS is essential, as it lives with the motor from the cradle to the grave and can help you spot issues that could cause poor electrical reliability. MCA calculates a motor’s TVS by taking measurements on all three phases of a motor. After taking these measurements, they’re put through a proprietary algorithm that produces a single number.

Reference Value Static

When a baseline test is taken on a new or recently repaired motor, the TVS value is referred to as the Reference Value Static (RVS). This value lives with the motor until it fails and is commonly referred to in future tests. With MCA, you can then compare the baseline RVS and a new TVS. If these values show a deviation of over 3%, a fault is likely developing, meaning you should troubleshoot further.

By quickly calculating RVS and TVS and comparing the results, MCA systems help you increase electrical reliability. When your readings show higher-than-acceptable deviations, you can make repairs before the motor’s electrical reliability is severely impacted.

MCA Software

Another way MCA equipment helps improve electrical reliability is through its incorporation of software. MCA software allows you to create a route that guides you to the most critical motors at your facility to prevent unnecessary downtime and save money.

MCA can detect developing turn to turn, coil to coil and phase to phase faults before any other motor testing technology. By detecting these faults, the software allows you to make a maintenance and repair plan to protect your motor’s electrical reliability and prevent failure.

Motor testing software also allows users to efficiently organize test records and trend results over time. With historical records, you can more easily determine when equipment’s health is decreasing and has the potential to fail — ensuring your motors deliver consistent electrical performance.


MCA Testing Applications

MCA testing has many applications designed to check your motor’s electrical health and ensure everything is working appropriately. Find out more about the primary MCA testing applications below:

  • Incoming inspection: Even new motors can fail, and MCA ensures a new piece of equipment is in working order before you start using it. With MCA, you can perform an incoming inspection to evaluate the health of a new or recently rebuilt piece of equipment. This testing eliminates the chance of installing a defective motor that won’t operate correctly once installed.
  • Commissioning: Before installing a motor from the stock shelf, you can use MCA for commissioning, where you conduct a motor test to establish a baseline test result. This result gives you a value to reference in the future to determine a change in the motor system. Once the motor is installed in the machine, you can take another baseline test directly from the MCC. You then have two baseline tests to compare to future tests to evaluate the overall condition of the motor system
  • Troubleshooting: If a motor develops issues like intermittently tripping a motor drive, drawing too much current, or overheating; a Motor Circuit Analysis test should be performed directly at the MCC. If a fault is identified, then a second test should be conducted directly at the motor. If the fault remains, the fault can be isolated to the motor and appropriate action can be made to replace the motor or send it to a rebuild facility to have it repaired. If the fault clears at the motor, then there is most likely an issue from the MCC to the motor cables. At this point, the motor cables should be analyzed as well as any connections made at a local disconnect or magnetic contactor. Corrosion due to moisture and high humidity can create high resistant connection points or even loose connections creating an impedance or resistance imbalance which will eventually lead to excessive heat and or imbalanced current draw of the motor. Without corrective action, this will greatly reduce the life of the motors and motor cables in the system and possibly cause safety implications.
  • Preventive and predictive maintenance: Minimize downtime and plan for potential motor failures by implementing a predictive maintenance program on your most critical machines. With MCA software, you can save money and prevent downtime by creating a route that guides you to your most essential motors. Specific measurements can also be trended to help identify developing motor faults before they become a concern. By trending test results with the Motor Circuit analysis software a technician can create easy-to-read reports and once the results hit predetermined criteria the technician can create a plan to have that motor replaced before it fails to ensure the least amount of downtime as possible. With MCA’s ability to find faults faster than any other motor testing technology, you can easily catch issues early and perform preventive maintenance.

Choose ALL-TEST Pro for Your MCA Equipment Needs

Choose ALL-TEST Pro for Your MCA Equipment Needs

At ALL-TEST Pro, our motor current signature analysis equipment is among the best on the market today. We have a variety of motor testing software equipment and hand-held MCA equipment available, such as the ALL-TEST PRO 7™ PROFESSIONALALL-TEST PRO 34 EV™MOTOR GENIE® Tester and ALL-TEST PRO 34™. Our broad selection ensures you can find a perfect fit for your equipment and testing requirements. By using our equipment, you can maximize your motors’ efficiency and productivity and give your maintenance team the tools they need to stay on top of your motors’ health.

Review our MCA testing products today. If you have any questions, feel free to contact us or request a free quote.

Get A Quote


How to Check Motor Winding Resistance on Single & Three-Phase Motors

For a quick review on this topic, please click this link. We cover Groundwall Insulation testing, how to test your windings for connection issues including open & shorts. 

What Is a Motor Winding Resistance Test?

Testing windings on a 3 phase motor is very easy with Motor Circuit Analysis™ (MCA™). Winding resistance measurements detect various faults in motors, generators, and transformers: shorted & open turns, loose connections, and broken conductors & resistive connections problems. These issues may be the cause of wear or other defects in a wound rotor motor. Winding resistance measurements detect problems in motors that other tests may not find. Instruments such as megohmmeters and ohmmeters will detect direct ground faults but will not indicate if the insulation is failing, turn to turn faults, phase unbalance, rotor issues, etc. If the motor is grounded, the megohmmeter & ohmmeter will solve your issue when you ohm a motor but if the motor problem is not a ground issue, you are going to need to use another tool or instrument to troubleshoot the problem since the motor maybe still operational but having issues such as tripping the VFD or circuit breaker, overheating, or underperforming, etc.

Motor Circuit Analysis™ (MCA™) is a test method that determines the true state of health of 3 phase & single-phase electrical motors. MCA™ checks the motors coils, rotor, connections, and more. MCA™ can verify ac motor winding resistance as well as dc motor resistance and determine state of health.

Motor Winding Resistance Unbalance or Connection Issues

MCA™ instruments give you results on screen and the test takes less than 3 minutes to perform and does not require additional interpretation and or calculations. The motor health is determined quickly with high accuracy and ease. All components of the single and three-phase motors are evaluated to determine the health of the complete motor.

Get A Quote

Connection issues create current unbalances between the phases in a three-phase motor, which causes excess heating and premature insulation failure. Resistance unbalance indicates connection issues that can be caused by loose connections, corrosion, or other buildups on the motor terminals. High Resistance connections can also occur which can cause excessive heat at the connection point that could lead to a fire damaging equipment and causing a safety hazard. A second test at the motor leads is required to pinpoint the issue if the initial test was performed at the motor control center (MCC). This direct test at the motor leads will confirm the motor state of health and will either condemn the motor or determine the associated cabling as the root issue. Many healthy motors are rewound and put back into operation only to have the same preliminary issue unresolved.

MCA™ testing technology gives in-depth information about the state of the motor’s components, including the insulation and windings. Plus, it works with single-phase and three-phase motors and AC and DC testing.

Get A Quote

Testing AC Motor Windings

The AT34™ & AT7™ instrument’s on-screen instructions guide you through the process. The measurements are automatic, and the test leads do not have to be moved once connected. This means that you can check single phase motors and three phase motors accurately and without additional steps to perform the test. Software suites (single user to enterprise suites are available) that are easy to use enabling you to tend, track and share information on all your motor assets and additional equipment.

Get A Quote

Testing DC Motor Windings

DC motors can have windings arranged in series, shunt or compound configurations.

When testing a DC motor with a  standard ohm meter multiple tests are generally required to ensure accurate and consistent results. The technician is required to compare the values from the test to those published by the motor’s manufacturer to determine if a problem exists. By using MCA™ technology, testing the windings does not require knowledge about the motor’s specific published values or extensive electrical information. In fact, MCA™ products allow for entry-level technicians to get accurate, clear results in three minutes that do not require any interpretation. The DC motor winding testing procedure is the same as the AC motor testing procedure. The recommended method is to take a baseline test of a new or freshly rebuilt motor. Once the motor is reinstalled the baseline test can be trended with future tests to determine a change in the motor system which will eventually develop into a motor fault. ALL TEST Pro’s line of deenergized instruments has simple on-screen instructions and data saving features that eliminate errors, calculations, and reference values required for troubleshooting and trending motors.  ATP uses Test Value Static™ (TVS™) as an indicator to track the lifecycle of individual motors. This value tracks the motor asset from cradle to the grave (installation to decommissioning). This value changes as the asset ages and will help you trend the motor and its current state of health.

Motor Circuit Analysis testing is a deenergized method that will thoroughly assess the health of your motor. It is easy to use and quickly delivers accurate results. The ALL-TEST PRO 7™ALL-TEST PRO 34™, and other MCA™ products can be used on any motor to identify potential issues and avoid costly repairs. MCA™ fully exercises the motors winding insulation system and identifies early degradation of the winding insulation system, as well as faults within the motor that lead to failure. MCA™ also diagnoses loose and faulty connections when the tests are performed from the motor controller. Find out more ways MCA outperforms other testing equipment in our video.


The ALL-TEST PRO 7™ conducts deenergized testing of a single-phase or three-phase motor. With its broad range of testing capabilities, this portable device can test AC and DC motors, motors above and below 1 kV, generators, transformers, and any other coil-based equipment.

Get A Quote


The ALL-TEST PRO 34™ is ideally suited for deenergized testing of AC induction squirrel cage rotor motors that are rated for less than 1 kV. This model offers the same high-quality, simple testing capabilities as the ALL-TEST PRO 7™, including an easy-to-read screen that displays instructions and a health assessment of the motor’s components.

Both units have ATP’s patented rotor dynamic test for determining rotor condition & Test Value Static (TVS™) for tracking motor health from the initial start-up to termination or repair. Features include portability, in-the-field design (no AC power required, no additional laptop, weighs under 2 lbs., weatherproof, easy to use, long battery life, & safe and easy to operate. 

Get A Quote

Buy MCA Motor Testing Equipment Today

ALL-TEST Pro ONLY develops, designs, and manufactures motor testing equipment. We serve all industries worldwide that utilize electrical motors. Our customers range from small shops to fortune 100 & 500 companies, government, military, and EV auto manufacturers. Find out why our customers are relying on ALL-TEST Pro to pinpoint the problem and as the final say when it comes to motor status.

In under three minutes, you get the answers you need to troubleshoot single and three phase motors, as well as trending capabilities. Check out our video for more about our motor winding testing products.

To get pricing information for any of our motor testing options, request a quote today or contact our team online at ALL-TEST Pro

Get A Quote


How to Test Motor Windings On Three Phase Motors

Los bobinados del motor son hilos conductores enrollados alrededor de un núcleo magnético; proporcionan un camino para que la corriente fluya y cree entonces un campo magnético para hacer girar el rotor. Como cualquier otra pieza del motor, el bobinado puede fallar. Cuando fallan los bobinados de un motor, rara vez lo hacen los conductores propiamente dichos, sino el revestimiento de polímero (aislamiento) que rodea a los conductores. El material polimérico es orgánico en su composición química y está sujeto a cambios debido al envejecimiento, la carbonización, el calor u otras condiciones adversas que hacen que cambie la composición química del material polimérico. Estos cambios no pueden detectarse visualmente, ni siquiera con los instrumentos tradicionales de comprobación eléctrica, como ohmímetros o megaohmímetros.

El fallo repentino de cualquier pieza del motor provocará pérdidas de producción, mayores gastos de mantenimiento, pérdidas o daños al capital y, posiblemente, lesiones personales. Dado que la mayoría de los fallos de aislamiento se producen con el tiempo, la tecnología MCA proporciona las mediciones necesarias para identificar estos pequeños cambios que determinan el estado del sistema de aislamiento del devanado. Saber cómo comprobar los bobinados permitirá a su equipo ser proactivo y tomar las medidas adecuadas para evitar fallos indeseados en el motor.

Cómo comprobar el aislamiento de la pared de tierra

Un fallo a tierra o un cortocircuito a tierra se produce cuando el valor de resistencia del aislamiento de la pared de tierra disminuye y permite que la corriente fluya a tierra o a una parte expuesta de la máquina. Esto crea un problema de seguridad, ya que proporciona una vía para que la tensión de alimentación del bobinado se extienda hasta el bastidor u otras partes expuestas de la máquina. Para comprobar el estado del aislamiento de la pared de tierra, se realizan mediciones desde los cables de bobinado T1, T2, T3 a tierra.

Las mejores prácticas comprueban la trayectoria del bobinado a tierra. Esta prueba suministra una tensión continua al bobinado del motor y mide cuánta corriente fluye a través del aislamiento hasta la toma de tierra:

1) Pruebe el motor sin corriente utilizando un voltímetro que funcione correctamente.

2) Coloque ambos cables de prueba del instrumento a tierra y verifique una conexión sólida a tierra del cable del instrumento. Mida la resistencia del aislamiento a tierra (IRG). Este valor debe ser 0 MΩ. Si aparece cualquier valor distinto de 0, vuelva a conectar los cables de prueba a tierra y vuelva a realizar la prueba hasta obtener una lectura de 0.

3) Retire uno de los cables de prueba de tierra y conéctelo a cada uno de los cables del motor. A continuación, mida el valor de la resistencia de aislamiento de cada cable a tierra y verifique que el valor supera el valor mínimo recomendado para la tensión de alimentación de los motores.

NEMA, IEC, IEEE, NFPA proporcionan varias tablas y directrices para la tensión de prueba recomendada y los valores mínimos de aislamiento a tierra en función de la tensión de alimentación de los motores. Esta prueba identifica cualquier punto débil en el sistema de aislamiento del muro de tierra. El factor de disipación y la prueba de capacitancia a tierra proporcionan una indicación adicional del estado general del aislamiento. El procedimiento de estas pruebas es el mismo, pero en lugar de aplicar una tensión continua, se aplica una señal alterna para proporcionar una mejor indicación del estado general del aislamiento de la pared de tierra.

Cómo comprobar si los devanados están conectados, abiertos o cortocircuitados

Problemas de conexión: Los problemas de conexión crean desequilibrios de corriente entre las fases de un motor trifásico, provocando un calentamiento excesivo y un fallo prematuro del aislamiento.

Aperturas: Las aperturas se producen cuando un conductor o conductores se rompen o separan. Esto puede impedir que el motor arranque o hacer que funcione en una condición “monofásica”, lo que genera un exceso de corriente, el sobrecalentamiento del motor y un fallo prematuro.

Cortocircuitos: Los cortocircuitos se producen cuando el aislamiento que rodea a los conductores del bobinado se rompe entre los conductores. Esto permite que la corriente fluya entre los conductores (cortocircuito) en lugar de a través de ellos. Esto crea un calentamiento en la avería que provoca una mayor degradación del aislamiento entre los conductores y, en última instancia, conduce al fallo.

Para comprobar si hay fallos en el bobinado, es necesario realizar una serie de mediciones de CA y CC entre los cables del motor y comparar los valores medidos; si las mediciones están equilibradas, el bobinado está bien; si están desequilibradas, se indican los fallos.

Las medidas recomendadas son:

1) Resistencia

2) Inductancia

3) Impedancia

4) Ángulo de fase

5) Respuesta en frecuencia actual

Compruebe el estado de su bobinado comprobando estas conexiones:

  • T1 a T3
  • T2 a T3
  • T1 a T2

La lectura debe estar entre 0,3 y 2 ohmios. Si es 0, hay un cortocircuito. Si es superior a 2 ohmios o infinito, hay un abierto. También puedes secar el conector y volver a probarlo para obtener posiblemente resultados más precisos. Compruebe si hay marcas de quemaduras en los insertos y si los cables están desgastados.

El desequilibrio de la resistencia indica problemas de conexión, si estos valores están desequilibrados en más de un 5% respecto a la media, esto indica una conexión suelta, de alta resistencia, corrosión u otras acumulaciones en los terminales del motor. Limpie los cables del motor y vuelva a probar.

Las aperturas se indican mediante una lectura de resistencia o impedancia infinita.

Si el ángulo de fase o las respuestas de frecuencia de la corriente están desequilibrados en más de 2 unidades respecto a la media, esto puede indicar cortocircuitos en el devanado. Estos valores podrían verse afectados por la posición del rotor de jaula de ardilla durante la prueba. Si la impedancia y la inductancia están desequilibradas en más de un 3% con respecto a la media, se recomienda girar el eje aproximadamente 30 grados y volver a realizar la prueba. Si el desequilibrio sigue la posición del rotor, el desequilibrio podría ser el resultado de la posición del rotor. Si el desequilibrio sigue siendo el mismo, se indica un fallo del estátor.

Los instrumentos tradicionales de comprobación de motores no son capaces de comprobar o verificar eficazmente los devanados de los motores

Los instrumentos tradicionales utilizados para comprobar motores han sido el megóhmetro, el ohmímetro o, a veces, un multímetro. Esto se debe a la disponibilidad de estos instrumentos en la mayoría de las fábricas. El megóhmetro se utiliza para pruebas de seguridad de equipos o sistemas eléctricos y el multímetro para realizar la mayoría de las demás mediciones eléctricas. Sin embargo, ninguno de estos instrumentos por sí solos o combinados proporciona la información necesaria para evaluar correctamente el estado del sistema de aislamiento de un motor. El megóhmetro puede identificar puntos débiles en el aislamiento de la pared de tierra del motor, pero no proporciona el estado general del sistema de aislamiento. Tampoco proporciona información sobre el estado del sistema de aislamiento del devanado. El multímetro identificará problemas de conexión y aperturas en los devanados del motor, pero no proporciona información sobre el aislamiento entre los devanados.

Compruebe los devanados con la prueba de análisis de circuitos del motor (MCA™)

La prueba de Análisis del Circuito del Motor (MCA™) es un método sin tensión que evaluará a fondo la salud de su motor mediante la comprobación de bobinados y otras piezas. Es fácil de usar y proporciona rápidamente resultados precisos. ALL-TEST PRO 7™, ALL-TEST PRO 34™ y otros productos MCA™ pueden utilizarse en cualquier motor para identificar posibles problemas y evitar costosas reparaciones. El MCA ejercita completamente el sistema de aislamiento del bobinado del motor e identifica la degradación temprana del sistema de aislamiento del bobinado, así como los fallos dentro del motor que conducen al fallo. MCA también diagnostica las conexiones sueltas y defectuosas cuando se realizan pruebas desde el controlador del motor.

Solicite hoy mismo un presupuesto para equipos de comprobación de motores

Las pruebas de motores son necesarias porque los motores fallan, y las pruebas pueden identificar problemas que evitarán fallos. En ALL-TEST Pro, disponemos de una amplia selección de productos de comprobación de motores adecuados para muchas industrias. Hemos trabajado con técnicos de procesamiento de alimentos, pequeños talleres de motores, reparación eléctrica y mucho más. En comparación con la competencia, nuestras máquinas son las más rápidas y ligeras, al tiempo que proporcionan resultados valiosos sin necesidad de interpretar datos adicionales.



Beginner’s Guide to Motor Testing

Motors when installed play a critical role in many manufacturing efforts. Businesses in all industries rely on machines to drive profits, so testing these motors ensures your investments are available for demanding tasks.

ALL-TEST Pro removes the mystery from motor testing by providing easy to use, handheld instruments to provide step by step procedures to quickly and easily test, even the most complex motors, from the controller or directly at the motor itself. Whether it has been months since your last equipment inspection or are just curious about the status of installations, ALL-TEST Pro wants you to understand that testing a motor for the first time is not as scary as it seems.

Why Is Motor Testing Important?

Motor testing improves machinery and plant availability by eliminating unscheduled machinery shutdowns and failures. Maximized revenue is achieved when these critical machines are operating, so testing motors must be a top priority for a successful company.

With the proper instruments effective and complete motor testing takes just moments to perform.

1. Not All Motor Faults Are Obvious

Physical senses of sight and sound provide a valuable indication of the proper operation of motors, but usually, by the time these senses are aware a fault is present, severe and expensive damage has already occurred. ALL-TEST Pro instruments provide the tools and measurements that identify faults in all motors or other electrical equipment before permanent and expensive damage occurs. The instruments can locate loose connections, degrading insulation or other faults that may arise from changing temperatures, multiple start-ups, or excessive vibration.

2. Identify Motor Issues as They Develop

Insulation, windings, stators and other motor components experience wear and tear over time. Knowing the condition of the motor’s insulation is critical for extended trouble-free operation. ALL-TEST Pro devices enable you to confirm good motors as well as identify developing motor problems beyond typical ground faults. (Ground faults occur when weaknesses develop in the insulation between the motor windings or any other energized part of the motor and the motor frame. This insulation is normally referred to as “groundwall insulation”.)

3. Motor Testing Promotes Safety Initiatives

Motors that overheat are a danger to employees, plants or facilities. User-friendly instruments by ALL-TEST Pro measure resistance unbalances and other developing faults that cause motors to overheat with a high level of sensitivity and accuracy. They help pinpoint where a repair is necessary before an issue occurs.

Common Motor Testing Procedures for Beginners

ALL-TEST Pro instruments provide on screen detailed step-by-step testing instructions on how to test motors and the results of tests in plain language, eliminating the need to spend time reviewing and analyzing colorful but meaningless graphs.

  • Low-voltage motor testing:Locate faults between conductors in the motor windings. ALL-TEST Pro instruments send low-voltage AC signals through motors winding systems to fully exercise the motor’s insulation to identify insulation degradation in the very early stages to ensure safe operation using non-destructive motor testing.
  • Insulation resistance testing: The ALL-TEST PRO 34™ provides further insight into the overall condition of the motor’s groundwall insulation. Megohmmeters only detect weaknesses in the insulation between the winding and ground. Our MCA™ testing solution fully tests the condition of motor groundwall insulation as well the ability to detect faults in the stators, rotors, cables and all insulation systems. Additional testing techniques quickly test the groundwall insulation to diagnose moisture problems, cracking, thermal degradation and early deterioration within the motor system. These tests eliminate the need for time-consuming time-based insulation tests such as the polarization index.

How to Test a DC Motor Safely

Beginners should follow all basic electrical safety tips when motor testing. For those new to the motor testing process, ALL-TEST Pro provides step-by-step guide outlined below you can reference when using MCA solutions for deenergized motors:

  1. Disconnect wired connections running between the motor and DC battery.
  2. Look for uninsulated portions of the conductor to perform the test.
  3. Ensure the DC voltage to the motor is disconnected from all parts of the equipment.
  4. Using a “confirmed” working voltage tester, verify all power has been removed from the motor leads that are going to be tested.
  5. Fasten test lead clips to motor listed motor leads.
  6. Select the winding test from the testing menu on the testing instrument.
  7. Connect the proper instrument test lead to the correct motor lead before performing tests.
  8. Follow the on-screen instructions to test the entire motor coils.
  9. Always refer to your motor’s manufacturing manual to be certain of connections.

ALL-TEST Pro Products for Accurate Motor Testing

ALL-TEST Pro specializes in portable devices ideal for deenergized motor testing. When testing a DC motor, products such as the ALL-TEST PRO 34™ and MOTOR GENIE® give you real-time information about ground faults, internal winding faults, open connections and levels of contamination within your setup.

Request a quote for our motor testing instruments today.


Easy Motor Testing Procedures

Los profesionales de las industrias manufacturera, de generación de energía y del agua confían en los motores eléctricos para completar sus objetivos. Para seguir siendo eficientes, es esencial que los sistemas basados en motores se mantengan en condiciones óptimas de funcionamiento. Un fallo repentino del motor puede producirse cuando menos se lo espera, por lo que conocer los procedimientos para realizar pruebas rápidas del motor le ayudará a maximizar el tiempo de actividad.

Que un motor eléctrico suene como si funcionara no significa que todos los componentes del sistema sean fiables. Los operadores de equipos tienen la posibilidad de probar motores eléctricos rápidamente con los dispositivos fabricados por ALL-TEST Pro.

Razones para probar los motores de forma rutinaria

Los motores eléctricos alimentan sistemas que generan beneficios para su empresa. La comprobación de motores es relativamente sencilla, y los instrumentos de ALL-TEST Pro proporcionan un verdadero estado de salud con una comprobación rápida de los motores. Detectar los problemas de un motor eléctrico antes de que se produzca una parada completa del sistema garantiza su capacidad para seguir cumpliendo los plazos.

Todos los motores eléctricos sufren desgaste debido al exceso de vibración y calor. Determinadas industrias se ven obligadas a utilizar sus equipos 24 horas al día, 7 días a la semana, 365 días al año. Es esencial conocer el estado de salud del motor y mitigar los problemas. La sencilla comprobación de motores determinará el estado de su equipo en pocos minutos gracias a la tecnología ALL-TEST Pro.


Solicitar presupuesto

Pruebas de análisis de circuitos de motores (MCA™)

Análisis del circuito del motor (MCA™) realiza una serie de pruebas desenergizadas localmente en el motor o más convenientemente desde el Centro de Control del Motor (MCC). Estas pruebas patentadas sin tensión determinan el estado del motor al ejercitar el devanado del motor y el sistema de aislamiento de la pared de tierra. Los fallos en el rotor, el cable, el controlador o el estator del motor se evalúan y notifican de forma rápida y sencilla mediante instrucciones en pantalla y muestran al instante el estado del motor con resultados fáciles de entender como bueno, malo o una advertencia.

El MCA™ también se puede utilizar para la resolución de problemas de disparos o fallos del sistema del motor, lo que ahorra horas de conjeturas tratando de separar los fallos mecánicos de los eléctricos o una resolución de problemas más profunda mediante la rápida evaluación e identificación de fallos en toda la parte eléctrica del sistema del motor.

Pruebe motores eléctricos rápidamente con MCA™

Inicial MCA™ inicial se realiza desde el CCM. Evalúa todas las conexiones, el cableado y otros componentes entre el punto de prueba y el propio motor utilizando cualquiera de los múltiples instrumentos portátiles ALL-TEST Pro. Si se detectan uno o varios fallos desde el CCM, basta con volver a realizar la prueba progresivamente más cerca del motor para localizar y aislar el fallo.

En las siguientes secciones encontrará más información sobre los problemas más comunes de los motores y lo que nuestros dispositivos pueden comunicarle sobre su equipo:

1. Fallos del devanado

Se calcula que el 37% de las averías de los motores de inducción se deben a fallos en los devanados. Los fallos del bobinado del motor se producen debido a fallos en el sistema de aislamiento. Los fallos de aislamiento están causados por la contaminación, el desgaste, la edad o la degradación térmica y, por lo general, comienzan con cambios muy pequeños en la composición química del material aislante y empeoran con el tiempo. La identificación temprana y la corrección de estos fallos evitarán fallos no programados, tiempos de inactividad y evitarán fallos catastróficos y mitigarán cualquier daño causado por un fallo en el bobinado.

La organización, las tendencias, la evaluación y la elaboración de informes sobre los datos resultan sencillas gracias al software interactivo compatible con los productos ALL-TEST Pro.

Solicitar presupuesto

2. Problemas de resistencia

La resistencia eléctrica entre los devanados del motor se mide en ohmios. Los óhmetros son herramientas útiles para determinar la resistencia de los conductores, pero no son los conductores los que fallan en los equipos eléctricos, sino el aislamiento que rodea a los conductores que forman las bobinas o devanados. Los óhmetros aplican una tensión conocida a un circuito y miden la cantidad de corriente creada por la resistencia del circuito. La resistencia del bobinado viene determinada por el tipo de material conductor, el diámetro y la longitud del conductor, pero proporciona una indicación “cero” del estado del aislamiento que rodea al conductor. Sin embargo, esta medición localizará devanados abiertos, conexiones sueltas o fallos graves en el material aislante cuando la resistencia del aislamiento entre conductores sea inferior a la resistencia del conductor alrededor del fallo.

Por ejemplo, un cable de cobre de calibre 22 tiene una resistencia de 0,019 ohmios por pie, si la circunferencia de una bobina es de 3 pies, la resistencia de 1 vuelta es de 0,057 Ω. Si cada bobina tiene 70 espiras la resistencia de cada bobina sería de 3,99 Ω. Si el estator trifásico tiene 24 bobinas cada fase tendría 8 bobinas en serie cada fase tendría 31,92 Ω. Por lo tanto, si se cortocircuitaran directamente 2 espiras, la resistencia de la fase sería de 31,863 Ω. Esto no suele estar dentro del rango de precisión de la mayoría de los óhmetros.

Dado que la característica principal de la corriente es que toma el camino de menor resistencia del aislamiento, los conductores deben degradarse hasta que sea < 0,057Ω antes de que la corriente cortocircuite alrededor de la bobina y pueda detectarse mediante la medición de la resistencia. En este ejemplo, 0,057/31,92 es 0,18% para el alambre de calibre 22, independientemente del tamaño del alambre, y los porcentajes seguirán siendo los mismos. Sin embargo, la medición de la resistencia es una indicación muy eficaz de conexiones sueltas, bobinas abiertas o posibles cortocircuitos completos entre fases.

3. Deterioro del aislamiento del bobinado

El ALL-TEST PRO 7™ PROFESIONAL está diseñado para probar todo tipo de equipos eléctricos con el fin de mejorar la productividad, fiabilidad y eficiencia en su planta de fabricación o instalación. La tecnología patentada MCA es compatible con motores de inducción de CA, generadores y transformadores, así como con motores y generadores de CC. La simplificación de los procedimientos de prueba permite a las instalaciones centrarse en las áreas problemáticas antes de que den lugar a costosas reparaciones. Los técnicos de planta comprueban motores de forma rápida y sencilla con dispositivos compactos, portátiles y aptos para instalaciones interiores y exteriores.

Los productos ALL-TEST Pro son lo suficientemente versátiles para todas las industrias. Considere la posibilidad de utilizar el ALL-TEST PRO 7™ PROFESIONAL para identificar desequilibrios sutiles que se extienden más allá de los fallos a tierra. Obtenga la información de diagnóstico que necesita para tomar una decisión informada sobre el mantenimiento preventivo, la supervisión del estado, la solución de problemas y mucho más.

ALL-TEST PRO 7™ y ALL-TEST PRO 7™ PROFESIONAL le ofrecen información sobre los siguientes aspectos:

Solicitar presupuesto

  • Test Value Static™ (TVS™) mide y define el estado general del aislamiento del bobinado y del sistema del rotor en motores de inducción trifásicos
  • La prueba dinámica evalúa rápidamente el estado del rotor o del aislamiento de los bobinados
  • Aislamiento de paredes de tierra; utiliza la resistencia del aislamiento para localizar y definir los puntos débiles del sistema de aislamiento de la pared de tierra, y el factor de disipación (DF) y la capacitancia a tierra (CTG) para determinar el estado general del sistema de aislamiento de la pared de tierra.
  • La impedancia e inductancia del devanado evalúa la orientación del rotor para determinar la validez de las pruebas de equilibrio de fases.
  • Los ángulos de fase y la respuesta en frecuencia de la corriente identifican pequeños cambios en la composición química del sistema de aislamiento del devanado

Más información sobre nuestros productos de comprobación de motores

Facilite sus pruebas de motores revisando los productos ALL-TEST Pro en línea. Distribuimos nuestras innovaciones en todo el mundo, y puede realizar una compra a través de dos canales de venta principales . Si desea más información sobre nuestros productos de comprobación rápida de motores rellene nuestro formulario de contacto para recibir un presupuesto.

Solicitar presupuesto


Buyer’s Guide: Which Multimeter Is Best for Your Next Project?

Despite its small size, a motor testing device is one of your business’s most critical tools. A motor can fail or malfunction at any time, which is why it is important to test for performance issues on a regular basis. The right multimeter is able to help detect certain electrical conditions such as if the motor is ungrounded or condemn a bad motor by testing each winding terminal. However, this tool does not troubleshoot motor issues in a comprehensive way which helps determine what is actually wrong with the motor or the repair that is required.

While there are a variety of multimeters on the market that can meet your testing requirements for many applications, they fail to meet the requirements needed for adequately testing motors. ALL-TEST Pro offers several high-quality testing tools that help you identify more abnormalities and meet higher efficiency standards.

What Kind of Motor Tester Do I Need?

Dozens of industries across the competitive market use motor testing tools to monitor the performance of their electrical equipment. At ALL-TEST Pro, we make instruments that determine the state of health of motors and cables, giving you reliable answers in an easy to understand format (good, bad, warn). We serve various markets and industries, including but not limited to:

Choosing the correct motor testing tool depends on the type of electrical equipment and the level of maintenance program you desire. For example, you may need a certain type of device depending on the power supplied or provided by the specific type of electrical equipment. Other factors to consider when you choose a tool include safety, price, and user frequency. If you’re working with high-power equipment and testing the motor while energized, extreme care should be taken that protects against dangerous voltages. 

Meanwhile, you might create a larger or smaller budget for your device depending on how you plan to use it. We have options that offer full predictive maintenance capabilities that internally store the test results so you can perform as many tests as needed throughout the day. There are also options available for different types of motors, from AC motors and DC motors to traction motors, transformers, generators, single phase coils, and any other electrical equipment with coils.

Choose ALL-TEST Pro Testing Tools

We have several types of motor testing equipment for industrial applications. ALL-TEST Pro instruments are superior to multimeters for electrical coil testing thanks to their speed and specialized range of capabilities. Our products use highly advanced technology and features to fully analyze the condition of your motor, which gives them an advantage over traditional tools for electrical coil testing.

One of our most popular pieces of motor testing equipment is the ALL-TEST PRO 7™ PROFESSIONAL. This product is a deenergized testing tool that’s both versatile and easy to use. It can analyze almost any type of motor, and it serves as an excellent form of prevention against failures and delays.

We also have a range of products in stock, including the ALL-SAFE PRO® and the MOTOR GENIE® Tester. Our options are ideal for both diagnostics and prevention, offering easily readable displays and intuitive controls. The ALL-TEST PRO 34 EV™ can even measure properties like contamination and the winding condition, depending on the test you choose.

Fill Out Our Quote Form

ALL-TEST Pro products give you more control over your projects by offering both convenience and testing accuracy in a small package. If you’re unsure what kind of motor testing equipment to get, we recommend reading more about the features and benefits our devices offer. Request a quote on our website today when you’re ready to buy.


Different Types of Multimeters Explained

Have you ever had a motor fail unexpectedly on the job? If so, you likely understand the importance of predictive maintenance and testing. Testing your motors regularly is a critical part of ensuring they perform at their best every day.

Kinds of Multimeters

There are many different types of motor testing instruments to choose from. The right tool will help you identify performance issues early and reduce downtime — and this could save you money in the long-run. 

One of the most common types of motor testing equipment is the multimeter. This instrument can be used to test several functions of your device. Most multimeters measure voltage, current and resistance, while the other variables require specialized instruments. Types of multimeters include:

  • The clamp digital multimeter
  • The multimeter
  • The autoranging multimeter
  • The analog multimeter

Different Types of Motor Testing Instruments Available From ALL-TEST Pro

Multimeters are used for motor testing due to their availability, but they provide very limited information regarding the condition of the motor and often results in eliminating the motor as the source of the problem. This results in unnecessary and ineffective maintenance or troubleshooting on other parts of the motor system components. ALL-TEST Pro provides the efficient solution to support your applications. We are a top source in the industry for different types of motor testing instruments, and our portable devices exceed the capabilities of any multimeter.

ALL-TEST Pro provides an entire range of motor testing instruments and accessories. These portable testing instruments are convenient and easy to use, and they’re designed to offer accurate instant results for both deenergized and energized motor testing. For example, you can rely on superior performance and technology with the ALL-TEST PRO 7™ PROFESSIONAL tool we have available. This tool is compatible with almost every type of AC and DC motor, as well as a variety of other devices. It’s also enhanced with our patented technology for optimal testing quality and versatility.

Other testing solutions we offer include:

Deenergized instruments:

Energized Instruments & Accessories:

You can use our testing options to identify motor abnormalities and address them before they start to impact your operations. They stand out among the different types of motor testing equipment thanks to their incredible precision and efficiency. Instead of detecting issues while they are occurring, these instruments help you predict failures from happening in the first place.

If you need a tool that can measure and troubleshoot from a distance, the ALL-TEST PRO 34™ could be the solution you’re looking for. Other options such as the MOTOR GENIE® Tester and the ALL-SAFE PRO® offer quick results so you can test as many devices as needed. Our testers go above and beyond, allowing you to analyze the full condition of the motor before taking on new projects.

Contact ALL-TEST Pro to Learn More

If you’re considering different types of motor testers for your latest applications, we have multiple energized and de-energized products in our inventory. While there are several kinds of multimeters available, you can benefit more from using a motor testing instrument from ALL-TEST Pro. We help you take control of your operations by providing a simple, accurate testing method that meets your exact requirements. Read more about our options today or contact us online for a quote.


AC vs. DC Motors

For those who have experience working with motors, you are likely quite familiar with the difference between AC and DC motors. If you are new to electrical motors or would like a refresher, we will explain. AC (alternating current) and DC (direct current) motors are fundamentally different. Each is comprised of different parts and components, and both produce power through directed electron flow.

The Difference Between DC and AC Motors

At the simplest level, the difference between DC and AC motors is they use different flows of electrons for sending power across lines. We will break down some of the primary differences:

  • DC motors: In a DC motor, electrons are pushed forward in a single direction. These motors are capable of producing high output and are an excellent source for conversion into AC power. DC power is more efficiently stored in batteries and is often used for storing energy.
  • AC motors: AC motors produce alternating current, which means electrons can move forward or backward. AC is the safer of the two for transmitting power over longer distances, as it retains more power when converted through transformers and distributed through a network.

Testing AC and DC Motors

Even with the best maintenance practices, the components in electrical motors have lifespans and will eventually fail. Testing AC and DC motors is a crucial step in ongoing maintenance to ensure their continued operation and optimal output. Even if the motor appears to be working well, an undetected fault could lead to component or system failure if left unaddressed. Typical motor tests include measuring:

  • Shaft and housing vibration
  • Temperatures of components
  • Torque and winding conditions
  • Component position and speed
  • Current and voltage generation

AC Versus DC Motor Tests

While tests for these motors are essentially looking for the same readings, the methods for testing will vary.

Using modern equipment, you can test motors while in an energized or deenergized state. These each have their advantages:

  • Energized testing: Energized testing occurs when equipment is under load to simulate normal operating conditions. This method helps uncover undiscovered or intermittent flaws by generating the heat and vibration standard to motor operation. Energized testing monitors all component performance, checking for wear and abnormal conditions that may require attention.
  • Deenergized testing: Deenergized testing runs diagnostics while machines are powered down. You can use deenergized testing equipment to test a new motor or system before powering on, or as an integral part of your preventive maintenance program. Our advanced testing can perform MCA™ (Motor Circuit Analysis), running complete checks on the entire electrical system.

Testing AC and DC Motors

A complete diagnostic check of your AC or DC motor typically involves multiple tests. Regardless of the type of test performed, always be sure to exercise safety precautions whenever working around electrical equipment. In most cases, testing AC and DC motors includes checking:

  • Current: Measure pull-in current by the shape of the arc and your peak amplitude.
  • Vibration: Look for any excessive vibration from your electrical motor components.
  • Temperature: Take readings of component temperature to check for abnormalities.
  • Alignment: If you have a rotating motor, check the shaft to ensure proper alignment.
  • Windings: Check the condition of your windings to locate damage and electrical shorts.
  • CDT: Track your CDT, or Coast Down Time, to monitor motor performance and degradation.

Advanced Diagnostic Equipment for Testing AC and DC Motors

Testing results will only ever be as good as the equipment used to read them. Visit ALL-TEST Pro for an incredible range of testing tools you can fit in the palm of your hand. We offer an extensive range of equipment for performing energized and deenergized testing. Our products deliver fast results you can rely on for testing the complex electrical systems found in the auto, steel, energy and utility sectors.

For information about purchasing ALL-TEST Pro testing equipment, please visit our online store.

Get A Quote