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How to schedule

To schedule private education for your group, contact:

Dale Shuter, CMP
Meetings & Expositions Manager

+1 314 993 2220, ext. 3335
dshuter@easa.com

1 hour of training

$300 for EASA Chapters/Regions
$400 for member companies
$800 for non-members

How a webinar works

All EASA private webinars are live events in which the audio and video are streamed to your computer over the Internet. Prior to the program, you will receive a web link to join the meeting. 

The presentation portion of the webinar will last about 45 minutes, followed by about 15 minutes of questions and answers.

Requirements

  • Internet connection
  • Computer with audio input (microphone) and audio output (speakers) appropriate for your size group
  • TV or projector/screen

Zoom logo

The Zoom webinar service EASA uses will ask to install a small plugin. Your computer must be configured to allow this in order to have full functionality. Please check with your IT department or company's security policy prior to scheduling a private webinar.

Private Webinars

EASA's private webinars are an inexpensive way to bring an EASA engineer into your service center, place of business or group meeting without incurring travel expenses or lost production time.

A closer look at accuracy of measuring and test equipment

A closer look at accuracy of measuring and test equipment

Mike Howell
EASA Technical Support Specialist

Inspection and testing are two of the most important activities performed by service centers. These activities involve the collection of two types of data: attribute data (go/no-go information) and variable data (measurement information). When collecting variable data or measurement information, service center technicians obtain data consisting of two components – the actual value of the measured dimension and the error associated with the measurement. The service center should be focused on minimizing measurement error such that the measurement values are as close to actual values as needed to properly evaluate the measured item.

This article covers:

  • Accuracy and precision
  • Calibration
  • Subcontracting calibration
  • In-house calibration
  • Calibration checks
  • What should be calibrated?

Available Downloads

A low-cost core test setup for small stators

A low-cost core test setup for small stators

Mike Howell
EASA Technical Support Specialist

The two primary reasons for performing stator core testing in the service center are (1) to verify that the stator core is acceptable for continued use and in the event of a rewind, (2) to verify that the repair process has not adversely changed the stator core condition. This testing can be done using a commercial core loss tester or a manual loop test using an appropriate AC source, cables and meters. Some typical reasons a manual loop test may be performed are: 

  • Customer or service center preference / specs 
  • Commercial core loss tester not available 
  • Stator size is inappropriate for available commercial core loss tester 

Additionally, some service centers have forgone core loss testing on small stators for various reasons including difficulties with test configuration, calculations, cost or even appearance. The purpose of this article is to explore a low-cost test setup for loop testing small stators.

Available Downloads

AC Motor Verification & Redesign - Ver. 4

AC Motor Verification & Redesign - Ver. 4

EASA's AC Motor Verification & Redesign - Ver. 4 software has been further refined and now contains and is fully integrated with EASA's Motor Rewind Database. This makes it the perfect program to lookup motor data, to verify existing winding data, and to perform motor winding redesigns.

This valuable resource is available only to EASA Members.

The AC Motor Verification and Redesign software provides easy verification of either concentric or lap windings, as well as redesigns with changes in poles/speed, horsepower, frequency or voltage. The redesign report with original and new winding data is output as an Adobe Reader (PDF) file and can be printed or saved. The program also allows you to search EASA’s extensive motor winding database. Choose to use the included database containing more than 250,000 windings or connect to the live, ever-expanding online database. Once found, motors from the database can be automatically imported as a starting point for further redesign.

Key software features include:

  • Improved redesign accuracy and database search options.
  • Includes the EASA Motor Rewind Database with more than 250,000 reported AC and DC windings. Use static built-in rewind database, or choose to use the constantly-updated, online database.
  • Allows multiple simultaneous input cases for comparison of different motors.
  • Users can opt to exclude half-wire sizes from automatic calculations.
  • Automatic conversion from AWG to metric wire and square/rectangular wire to round magnet wire.
  • The user can limit redesigns to only those matching in-stock wire sizes.
  • Standard "one line formula calculations" are available from the Reference menu.
  • Help files provide context-sensitive help. Includes the full EASA AC Motor Redesign book. Spanish translation of Help reference materials is provided.
  • Built-in reference tables for chord factor, coil grouping, distribution factors, flux densities, and more.

System requirements

  • Windows® XP, Windows® Vista, Windows® 7, 8 or 10 (Note: To run on a Mac, you must run a supported Windows OS using virtual machine software such as Parallels or Fusion.) 
  • CD-ROM or DVD drive
  • Approximately 1.25 GB free space on hard drive
  • Screen resolution of at least 1280x768 (with text size set at 100%)
  • Java™ Virtual Machine 1.8 or higher (Version 1.8 included on CD-ROM)
  • Adobe® Reader (for report output/printing; free download from https://get.adobe.com/reader/)
  • Internet access for retrieving future software updates and optional online motor rewind database

AC Motor Verification and Redesign and Motor Rewind Data Version 4 programs work together to offer more capabilities

AC Motor Verification and Redesign and Motor Rewind Data Version 4 programs work together to offer more capabilities

Gene Vogel
EASA Pump & Vibration Specialist

New features in the EASA AC Motor Verification and Redesign – Version 4 (ACRewind) program enhance the ability for members to submit data electronically for inclusion in EASA’s Motor Rewind Data – Version 4 (MotorDB) program. Jump to the section below on “enhancements” if you’re already familiar with these programs and how they work. 

The Version 4 software is a powerful set of tools for members to check the validity of winding data and to redesign windings from concentric-to-lap and for changes in motor performance. A key feature of this latest version of the program is the integration of the MotorDB with the ACRewind program. The availability of both program functions within a common user interface provides more than just convenience. The ability of the programs to share data resources creates new capabilities that the stand-alone version of the program could not.

Available Downloads

Are you in compliance with the OSHA standard regarding forklift training?

Are you in compliance with the OSHA standard regarding forklift training?

Richard Bashore 
Reading Electric 
Reading, Pennsylvania 
Management Services Committee Member 

In 1999, due to the large number of forklift accidents and deaths, U.S. OSHA Standard 29CFR1910.178 changed. The standard requires employers to train and authorize any employee who operates any type of specialized industrial truck powered by electric motor or internal combus­tion engine in the workplace. Mem­bers outside the U.S. likely have similar laws they must comply with. 

In addition, re-training is re­quired every 3 years or if there is a change of equipment, a near miss or accident in the workplace, or if the operator is handling the forklift in an unsafe manner. 

Available Downloads

Boring and sleeving bearing housings in a vertical milling machine

Boring and sleeving bearing housings in a vertical milling machine

Robert Giesen 
B & B Electric Motor Co. 
Wichita, Kansas 
Technical Education Committee Member 

Editor's Note: The procedures outlined in this article exclude explosion proof motor end bracket rebuilding.  

Many motor service centers bore and sleeve end brackets (end bells) in machine lathes. When using a lathe you need one large enough to swing the outside diameter of the end bracket and the large mass is hard to indicate true. Many times it is difficult to clamp onto the lathe chuck or faceplate. 

When rotating a large mass there is always a chance of the part coming loose and causing damage to the end bracket or injury to the machine opera­tor. We have bored and sleeved end brackets for more than 25 years in a vertical milling machine. We find the mill is a more useful machine; it is faster and more accurate to indicate in and set up. 

The boring of the diameters are true and concentric and it is much safer to rotate a cutting tool and not the part. Following is a step-by-step procedure to bore and sleeve end brackets in a verti­cal milling machine. 

Available Downloads

Building a portable variable-voltage AC and DC power supply

Building a portable variable-voltage AC and DC power supply

Constructing your own device with inexpensive, readily available components

Chuck Yung 
EASA Technical Support Specialist 

Rather than moving DC frames, strip heaters, etc. to the test panel for testing, wouldn’t it be convenient to have a portable and variable voltage supply? There are quite a few EASA members who have built a simple voltage supply using readily available components. 

Not only does it save timeless time spent using the crane to handle heavy parts – but such a voltage supply can be useful for field service jobs. This article will describe how to build it, provide a parts list, drawing of the complete unit, wiring diagram, and even suggest economical sources for some of the items. 

Available Downloads

Características y Beneficios del manual: Obteniendo Lo Máximo De Su Motor Eléctrico de EASA

Características y Beneficios del manual: Obteniendo Lo Máximo De Su Motor Eléctrico de EASA

Tom Bishop, P.E.
Especialista Sénior de Soporte Técnico de EASA

Para los centros de servicio, el manual Obteniendo Lo Máximo De Su Motor Eléctrico de EASA es una gran herramienta de mercadeo que pueden suministrar a sus clientes (usuarios finales). Como tal, este valioso documento de 40 páginas, proporciona a los usuarios finales información que les ayudará a obtener una operación más durable, eficiente y rentable de motores trifásicos de propósito general y de propósito definido con las siguientes características:

  • Motores trifásicos de inducción de jaula de ardilla fabricados bajo normas NEMA MG1
  • Potencias entre 1 y 500 hp (1 a 375 kW)
  • Velocidades entre 900 y 3600 rpm (8-2 polos)
  • Voltajes hasta 1000V, 50/60 Hz
  • Todos los tipos de encerramiento estándar (DP, TEFC, WPI, WPII)
  • Rodamientos de bolas y de rodillos y cojinetes de deslizamiento

La siguiente es una descripción general del contenido del manual indicando algunas formas de usarlo que pueden beneficiar a los usuarios finales, Ej. Sus clientes y sus clientes potenciales.

Instalación, arranque e información básica
La primera de las dos sesiones principales trata tres subtemas: Instalación del motor, arranque e información básica y al comienzo recomienda asegurarse de documentar el estado inicial del motor para establecer una base para compararla con resultados futuros. Además, los beneficios para el usuario final al seguir esta práctica, es que a menudo les permite detectar problemas pequeños o en formación, antes de que se conviertan en fallos caros y costosas pérdidas de producción.

El Apéndice A, “Datos básicos del motor y de su instalación” hace referencia a esto (ver Figura 1). Tomar los datos de placa y anotar los parámetros eléctricos y mecánicos al momento de la instalación y arranque del motor, permite que la información quede disponible para consulta, en papel o en formato electrónico, si es escaneada. La revisión de los datos del motor, incluyendo los de placa, puede proporcionar información sobre la idoneidad del motor para la aplicación.

Los puntos específicos a verificar son: Si el motor es adecuado para trabajar con un variador de frecuencia (VFD), si los rodamientos permiten instalarlo en una aplicación que requiere transmisión por correas, la accesibilidad a los puntos de lubricación y comprobar que las protecciones de sobre carga están bien calculadas para la potencia del motor. Los dos últimos puntos pueden resultar críticos si se trata de un motor de repuesto con una potencia nominal diferente a la del motor que está reemplazando.

Las consideraciones de la instalación, así como también la idoneidad de la fundación y de la base son importantes para la confiabilidad del motor. Una base débil o inadecuada puede distorsionar la carcasa, generar vibración o desgastar rápidamente los rodamientos.

El manual no solo proporciona detalles acerca de estos temas, sino que también cubre extensamente el alineamiento de los ejes, incluyendo el problema del pie suave, tolerancias y métodos de alineación para acoplamientos directos y para transmisión por poleas. El usuario final puede encontrar gran cantidad de información en tan solo unas pocas páginas del manual.

La información del manual procede de las consideraciones de instalación y de los procedimientos de arranque. En muchos casos, el motor que se está instalando ha estado almacenado. También se proporcionan detalles para ayudar a asegurarse que el motor funciona correctamente. Además del tema del almacenamiento, se incluyen otros relacionados con la lubricación y los lubricantes y la comprobación de la resistencia de aislamiento del bobinado (ver Tabla 1).

A continuación, se proporcionan recomendaciones para las pruebas de arranque previas a la operación del motor y se recomienda medir y registrar los niveles de vibración. Las pruebas recomendadas con el motor con carga incluyen medir los voltajes línea a línea, las corrientes de línea, la temperatura del bobinado (si es posible), la temperatura de los rodamientos y la temperatura ambiente. El manual sugiere que se registren dichos valores en la hoja de datos del motor para que sirvan como base para analizar las tendencias de futuras mediciones. Se suministran dos ejemplos para ilustrar la importancia de registrar los datos de referencia y sus tendencias.

Esta sección inicial concluye con la gestión total del motor. Generalmente, este tipo de programas rastrean las compras y los repuestos en una base de datos utilizando la información de la placa del motor y los datos de instalación / ubicación y aplicación. Por lo general, también realizan un seguimiento de los datos de referencia, mantenimiento, almacenamiento y reparación. Los principales beneficios para los usuarios finales son que dichos programas bajan los costos al reducir el tiempo de inactividad (los repuestos están disponibles) y el inventario es decreciente (identificación de los repuestos utilizados en múltiples ubicaciones).

Aquí, una consideración clave es determinar si la solución más rentable y confiable consiste en almacenar los motores de repuesto en el sitio o subcontratar el almacenamiento con un centro de servicio u otro proveedor. La gestión del motor y el almacenamiento de sus repuestos (y otros equipos) es una oportunidad adicional que tiene el centro de servicio para añadir valor al servicio prestado a sus clientes. Además, tener el motor de repuesto del cliente en sus instalaciones, brinda al centro de servicio una mejor oportunidad de recibir el motor que ha sido reemplazado para repararlo según sea necesario.

Seguimiento operacional​ y mantenimiento
La segunda de las dos secciones principales se ocupa del seguimiento operacional y el mantenimiento. Los temas principales incluyen condiciones específicas de la aplicación, mantenimiento preventivo y predictivo, inspección y pruebas y la relubricación de los rodamientos. Al utilizar las recomendaciones de esta sección, el usuario final puede prolongar la vida útil de sus motores, así como reducir el tiempo medio entre los fallos que requieren reparación.

Anomalías en el suministro eléctrico, como transitorios de voltaje, pueden dar lugar a transitorios de corriente y torques transitorios que pueden dañar no solo los devanados, sino también los componentes mecánicos del motor o del equipo accionado. Para ayudar al usuario final a evitar estos problemas, se suministra un listado que contiene diferentes apartados que identifican más de media docena de fuentes potenciales. Otra fuente de condiciones transitorias, que no es una anomalía, es el arranque del motor. El manual proporciona al usuario final una guía para manejar el arranque del motor y enfatiza la necesidad de limitar su número de arranques.

La subsección sobre mantenimiento preventivo (PM), mantenimiento predictivo (PdM) y mantenimiento basado en confiabilidad (RBM) define y describe cada uno de ellos. Las técnicas de inspección y pruebas eléctricas y mecánicas y la evaluación de la condición física se identifican para PM, PdM y RBM [también denominado mantenimiento centrado en la confiabilidad (RCM)]. Incluso si un usuario final ya tiene un programa de PM, PdM o RBM, se puede beneficiar al consultar esta subsección ya que podría identificar los elementos que le faltan a su programa. Además, si un usuario final no está familiarizado con ninguno de estos programas, el manual proporciona información sobre el proceso inicial para obtener una operación más confiable del motor. Es decir, brinda una oportunidad para que el usuario final aproveche al máximo sus motores eléctricos y probablemente también el equipo acoplado.

En la siguiente sección sobre inspección y prueba de motores se incluye información adicional sobre PM, PdM y RBM. Muy a menudo escuchamos la frase “no pase por alto lo obvio”. Esto describe la importancia de la inspección física para detectar partes que falten, o que estén rotas o dañadas, trayectorias de circulación de aire bloqueadas y contaminantes. Cualquiera de estas condiciones podría llevar a un fallo prematuro y rápido del motor.

Las pruebas descritas en detalle incluyen la resistencia de aislamiento, la resistencia del devanado y el análisis de firma de corriente del motor (vea la Tabla 2). Cuando están disponibles en las normas industriales, se proporcionan criterios de evaluación para que el usuario final pueda determinar si sus niveles son aceptables o justificar una acción correctiva y se suministra información de seguridad relacionada con las pruebas de hipot y de impulso de los motores instalados. También se proporciona información sobre el análisis de vibraciones empleando un analizador de espectro.

Esta subsección final del cuerpo principal del manual brinda orientación para ayudar a asegurar un funcionamiento prolongado y confiable del motor. Las recomendaciones incluyen no solo relubricar los rodamientos, sino también monitorear los niveles de lubricante y verificar si hay fugas y contaminación. Se proporciona orientación para ayudar al usuario final a determinar el intervalo correcto de relubricación y el tipo y grado de lubricante cuando las instrucciones del fabricante del motor no están disponibles.

Se enfatiza la importancia de la compatibilidad de las grasas y se proporciona un cuadro de incompatibilidad. Un consejo sabio para la relubricación se encuentra en la frase: “La mejor práctica consiste en usar la misma grasa que ya existe en los rodamientos, siempre que sea adecuada para la aplicación.” Se proporciona una fórmula para determinar la cantidad precisa de grasa requerida como también un gráfico que ilustra los intervalos de relubricación en función del tipo y tamaño de rodamiento y la velocidad del mismo.

También se aborda la lubricación de cojinetes de deslizamiento y rodamientos lubricados con aceite, incluidos temas como la compatibilidad y viscosidad del aceite e intervalos de relubricación. También se describen temas específicos, como el tratamiento de las condiciones anormales y cómo reemplazar el aceite.

Apéndices
Los tres apéndices proporcionan información complementaria que puede ayudar al usuario final a obtener más de sus motores en términos de la conservación de los registros, la comprensión de la terminología y el almacenamiento del motor. El Apéndice A contiene un formato de dos páginas (vea la Figura 1) destinado a registrar los datos de placa del motor y los datos de las pruebas eléctricas y mecánicas. Inicialmente, el formato se puede usar para obtener información de referencia y que se puede actualizar posteriormente cuando se realicen trabajos de mantenimiento o reparación. Como tal, puede proporcionar información histórica invaluable para el usuario final y las empresas de servicio cuando sea necesario realizar un análisis simple o un análisis de causa raíz de fallo más completo.

La información en el Apéndice B es una compilación de términos clave asociados con los datos de placa del motor. (Nota: También hay un glosario de términos independiente al final del manual). Sin embargo, el valor real de esta información está en determinar el significado de los términos que a veces se malinterpretan. Conocer el verdadero significado y la importancia de estos términos puede ayudar a un usuario final a evitar un error costoso y a emplear tiempo excesivo en la compra de un motor que no es adecuado para una aplicación específica.

Según las consultas de los miembros de EASA, las recomendaciones de almacenamiento del motor, que son tema del Apéndice C, son una solicitud común de los usuarios finales. Por sí solas, estas recomendaciones de almacenamiento hacen del manual un valioso recurso para los usuarios finales. La última página de este apéndice resume la frecuencia con la que se deben realizar ciertas rutinas de mantenimiento durante el almacenamiento. Es raro encontrar esta información actividad vs tiempo en un solo lugar, que es algo que muchos usuarios finales apreciarán.

Available Downloads

Cast iron component welding repair tips

Cast iron component welding repair tips

Here’s help on working with minor cracks to major reconstruction

Kent Henry 
Former EASA Technical Support Specialist

In the power transmission indus­try, a fair amount of cast iron is used. Whether it’s for motors, pumps, or gear reducers, many use cast iron for the bulk of their structure. This variety of usage results in service opportunities involving the repair of cast iron components. 

Cast iron has a very high carbon content, so much so that the concen­trations of carbon form graphite flakes that result in a high resistance to wear. The drawback of cast iron is that the high carbon content also makes castings brittle. Examples of brittle castings are terminal boxes and fan covers. If a forklift operator rounded a corner a little wider than normal and bumped into the terminal box and fan cover of a Totally Enclosed Fan Cooled (TEFC) motor made from steel, the impact would bend the steel components. Steel is a fairly ductile material. The repair of these parts may Figure 1. Example of crack prepared for welding. and fully weld this side of the be limited to hammering out dents in the terminal box and fan cover. If the same collision happened with cast iron components, the damage would be quite different. They would likely be cracked or even break into pieces due to the brittleness. 

Available Downloads

Cleaning electrical equipment with dry ice

Cleaning electrical equipment with dry ice

Cyndi Nyberg
Former EASA Technical Support Specialist

Dry ice is a relatively new alternative to grit or solvent cleaning of electrical equipment. It is often not feasible to have a motor taken out of service and sent to a shop for cleaning, either due to shear size or difficulty in dismantling the machine.

Transportation to and from the service center can also add considerable downtime that can be very costly. Dry ice is a practical alternative. Dry ice cleaning can be done on site with minimal downtime. It is possible to clean the external parts of a motor with dry ice without any interruption of service.

Available Downloads

Consider this aluminum frame motor burnout method

Consider this aluminum frame motor burnout method

Jacob Snyder
Evans Enterprises, Inc.

When a modern temperature controlled (i.e., controlled pyrolysis) burnout oven is not available, the method described here can be used to process aluminum frame motors.

Available Downloads

Consideraciones Importantes Para Acondicionar la Reparación de Bombas en su Centro de Servicio

Consideraciones Importantes Para Acondicionar la Reparación de Bombas en su Centro de Servicio

Gene Vogel
Especialista de Bombas & Vibraciones de EASA

Esto sucede en casi todos los centros de servicio de EASA, aparece una máquina para reparación, con cables y un motor, pero es una bomba. A menudo es una bomba sumergible o de acoplamiento cerrado. Si su respuesta es: “Aquí no reparamos estos equipos” y está pensando: “Nosotros no sabemos nada sobre reparación de bombas” puede que le esté dando la espalda a un trabajo muy rentable.

Como ya detallé en mi artículo publicado en Febrero en la revista Currents, la reparación de bombas puede ser un área de expansión muy rentable para los centros de servicio especializados solo en la reparación de motores eléctricos. Si usted está de acuerdo en que la reparación de bombas sería una buena opción para su negocio, el próximo paso consiste en evaluar qué cambios necesita en sus instalaciones para incluir la reparación de bombas. Encontrará que ya tiene gran parte del equipo necesario. Las características de los motores y de las bombas centrífugas son muy similares y dependiendo del tipo de bomba, puede que necesite muy poco equipo adicional.

Available Downloads

Consideraciones para la resolución de los equipos de prueba & medida (M&TE)

Consideraciones para la resolución de los equipos de prueba & medida (M&TE)

Mike Howell
EASA Technical Support Specialist

La precisión y exactitud de los equipos de prueba & medida (M&TE) han sido tratadas en artículos previos de Currents (noviembre y diciembre de 2014). Un tema relacionado que no fue cubierto en dichos artículos es la resolución. El documento JCGM 200:2012 del Joint Committee for Guides in Metrology define resolución como: “El cambio más pequeño en una cantidad medida que causa un cambio perceptible en la indicación correspondiente”. Simplificado, es la diferencia más pequeña que puede ser medida por el equipo en cuestión. La exactitud de la M&TE debe ser mayor (menos exacto) o igual a la resolución. Es decir, durante la calibración, el M&TE debe ser capaz de indicar el valor comparado con el estándar.

Precisión y exactitud
Repasemos brevemente la importancia de la precisión y exactitud. Al recoger la información de las medidas, los técnicos del centro de servicio obtienen datos con dos componentes: El valor auténtico de la medida (valor real) y el error asociado a la medida (componentes de precisión y exactitud). Así mismo, entre más pequeño sea el error de medida, más se acerca la indicación o valor medido a la medida real. Como lo muestra la Figura 1, a menudo los términos precisión y exactitud se demuestran y diferencian gráficamente utilizando el ejemplo de la diana.

La precisión se refiere al grado de repetibilidad y reproducibilidad en el sistema de medida, Repetibilidad es la capacidad que tiene un técnico para obtener la misma medida varias veces midiendo el mismo elemento con el mismo M&TE. Reproducibilidad es la capacidad de varios técnicos para obtener la misma medida midiendo el mismo elemento con el mismo M&TE. Normalmente, la precisión del M&TE es evaluada con estudios de repetibilidad & reproducibilidad (R&R).

La exactitud es el grado en el que la medida concuerda con el valor real. La exactitud de un M&TE es evaluada por calibración.

Resolución
De nuevo, podemos simplificar la resolución como la diferencia más pequeña que puede ser medida con nuestro M&TE. Aunque para cualquier medida la exactitud de nuestro M&TE se debe comparar con nuestro rango de tolerancia aceptable.  Tendemos a ver rápidamente la resolución de un indicador o medidor solo por observación. Por esta razón, la resolución es un buen “primer paso” cuando se selecciona un M&TE para una tarea específica. Es decir, si usted tiene una herramienta con una resolución de 1 cm y necesita medir algo con un diámetro nominal de 1 mm+/-0.1mm, ya debería saber que tiene la herramienta incorrecta para el trabajo. 

Existen algunos ejemplos obvios de malas elecciones que podemos identificar en un típico centro de servicio. Nunca pensaríamos utilizar una balanza industrial para pesar los pesos de balanceo o una regla para medir el diámetro de un alambre magneto. En estos dos casos, sabemos que la resolución de un M&TE probablemente es más grande que el valor medido; si la resolución no está ahí, seguramente la exactitud deseada no estará ahí. La selección del M&TE apropiado depende del propósito de la medición. Para balancear, muchos pueden considerar apropiada una balanza con una exactitud de 0.1 gramos que pese hasta 100 gr. Pero, los centros de servicio que balancean rotores de husillos o conjuntos extremadamente largos pueden necesitar algo diferente. 

Para el alambre magneto, la precisión y exactitud requeridas para identificar simplemente un calibre durante la toma de datos pueden ser muy diferentes a las requeridas para determinar si las dimensiones de una muestra de alambre magneto están dentro de la tolerancia de fabricación de las normas NEMA o IEC. Además, una galga para alambres nunca es una buena opción para medir alambres magneto.

Los M&TE escogidos por cada centro de servicio variarán de acuerdo con los requisitos de diferentes fuentes como clientes y entes reguladores o de certificación. Siempre deben evaluarse primero los requisitos de los clientes antes de tomar cualquier decisión sobre el proceso de negocios. Un centro de servicio cuyo cliente más importante es un lavadero de vehículos puede tener requisitos muy diferentes a uno que repara motores relacionados con la seguridad de una central nuclear. Sin embargo, todos los centros de servicio deben escoger los M&TE adecuados para darles una seguridad razonable en las actividades de seguimiento del proceso e inspección y pruebas que realizan.

Cuando se trata del seguimiento de procesos, para la mayoría de parámetros existen muchos medidores y sensores que varían ampliamente por rango, resolución y exactitud. Por ejemplo, si se usa un manómetro en un sistema VPI donde el proceso está calibrado a 80±5 psi (5.5±0.3 bar) y el manómetro tiene un rango de 0-150 psi (0-10.3 bar), es razonable tener una calibración limitada, tal vez de 70-90 psi (4.8-6.2 bar). La Figura 2 muestra un manómetro que puede usarse de esa forma.

Ahora, veamos un parámetro diferente que debe ser controlado durante el ciclo de vacío-VPI. Durante un proceso de impregnación global-VPI, existe una fase de vacío seco y algunas veces también una fase de vacío húmedo. Normalmente, los niveles de vacío seco deben estar por debajo de los 5 Torr (0.007 bar) y es deseable alcanzar un nivel menor o igual a 1 Torr (0.001 bar), especialmente en estatores con bobinas de pletina. El manómetro de la Figura 2 sirve para algún proceso industrial simple pero no es adecuado para las mediciones de vacío en el proceso VPI de un centro de servicio. Examinemos la resolución de la porción de vacío de la escala, desde 0 hasta 30 pul-Hg. La Tabla 1 muestra las unidades para convertir pul-Hg en Torr. Si estamos interesados en niveles de vacío seco menores o iguales a 5 Torr, resulta evidente por que el manómetro de la Figura 2 es inadecuado. No se puede diferenciar un vacío de 0.5 Torr de un vacío de 10 Torr.

Esto no significa que si su centro de servicio tiene un manómetro de vacío inadecuado, no esté logrando niveles de vacío aceptables- esto solo significa que usted no tiene un control de proceso adecuado y no sabe el nivel de vacío que está obteniendo. Una opción más razonable para medir el vacío en un sistema VPI se muestra en la Figura 3. Un manómetro similar a este puede tener un rango de 0.2 a 20 Torr y una exactitud del 20%.

Los centros de servicio deben evaluar cada medida que afecte la calidad del servicio o producto suministrado. Para cada uno, considere el rango de valores posible, así como también la precisión y exactitud de los M&TE necesarios para realizar el trabajo. incluso para los técnicos más calificados y experimentados, contar con los M&TE es crítico para la disposición adecuada de cualquier máquina o componente.

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Consideraciones sobre la fuente de alimentación al construir un gran growler

Consideraciones sobre la fuente de alimentación al construir un gran growler

Tom Bishop
EASA Senior Technical Support Specialist

Cuando se considera la construcción de un gran growler para probar rotores y armaduras, la decisión inicial típica es seleccionar la potencia en kVA. La razón principal para esto es que el growler necesitará ser conectado a una fuente de alimentación que tenga suficiente amperaje. Para ayudar a simplificar el complejo proceso de diseño, en este artículo hemos seleccionado cinco potencias expresadas en kVA. Uno de los valores de potencia seleccionados cumplirá con las necesidades de la mayoría de los centros de servicios.

Este artículo abarca:

  • Un ejemplo de diseño
  • Determinación de las vueltas y el tamaño del cable
  • Construyendo el núcleo
  • Determinación de las dimensiones de la bobina

Available Downloads

Considerations for measuring & test equipment (M&TE) resolution

Considerations for measuring & test equipment (M&TE) resolution

By Mike Howell
EASA Technical Support Specialist

Accuracy and precision of measuring & test equipment (M&TE) have been topics of previous Currents articles (November and December 2014). A related topic that was not covered in the previous articles is resolution. The Joint Committee for Guides in Metrology document JCGM 200:2012 defines resolution as “the smallest change in a quantity being measured that causes a perceptible change in the corresponding indication.” Simplified, it’s the smallest difference that can be measured by the subject equipment. The accuracy of the M&TE must be greater than (less accurate) or equal to the resolution. That is, the M&TE must be able to indicate the value that is compared to the standard during calibration.

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Considere este método para quemar un motor con carcasa de aluminio

Considere este método para quemar un motor con carcasa de aluminio

Jacob Snyder
Evans Enterprises, Inc.

El método aquí descrito se puede utilizar para procesar motores con carcasa de aluminio cuando no se tenga un horno moderno de quemado con temperatura controlada (es decir de pirolisis controlada).

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Controlled Environments and Cleanrooms Prevent Contamination in Service Centers

Controlled Environments and Cleanrooms Prevent Contamination in Service Centers

Tom Bishop
EASA Senior Technical Support Specialist

Occasionally we hear the term “cleanroom” used for a winding area that is physically isolated from the remainder of a service center (Figure 1). The main purpose of such an enclosure is to prevent windings and winding material from being contaminated with any dust and dirt (Figure 2) that may be in other parts of the service center. Some service centers construct these enclosures because they strive to provide the cleanest practical environment for winding work, and some also use the enclosure for the bearing installation process. Cleanroom type enclosures can also benefit facilities by helping minimize quality problems and increase the volume of acceptable product.

Here we will explore the distinction between a controlled environment and a cleanroom, the requirements for both, and provide details to help you determine if you want to add a controlled environment or a cleanroom to your facility.

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Creating User-Friendly Service Center Forms

Creating User-Friendly Service Center Forms

Bret McCormick
Stewart's Electric Motor Works, Inc.

Paperwork.

No one likes it on the shop floor. Nobody wants to fill out forms. 

Like most service centers, we recognize that accurate paperwork is a necessary part of any effective system for achieving product quality. But in our experience, it’s always been difficult to develop easy-to-use forms that will streamline the process of moving jobs through the shop. With those thoughts in mind, we at Stewart's Electric Motor Works set out to find a better way to create user-friendly forms.

We started by cramming a lot of information onto a single sheet of paper and, after much discussion, eventually settled on a template that could be used to expand the paperwork of each department.

To simplify the process of making specific repair forms, we used the Tables function in Microsoft® Word to create more than 60 building blocks for capturing common information like nameplate data, flux densities, accessories, instructions/notes, and so forth. We also developed a small library of generic drawings (e.g., horizontal and vertical motors, rotors, armatures, pump components, etc.) that could be incorporated into forms as needed.

Now whenever we need a new form, we just paste the appropriate building blocks into the department’s template and save the document with a new file name. Then we move the blocks around on the page as needed, modifying the labels, cell sizes, and numbers of rows as necessary before saving the document again. With this procedure, it’s fairly easy to create or revise forms for all aspects of repair–from motor and pump inspection and disassembly to machine work, rewinding, reassembly and final testing.

Since this process works so well for us at Stewart’s Electric, it might be helpful to you, too. You can download and view our building blocks, illustrations and generic PDF forms by downloading the ZIP file below (ZIP is an archive file format that contains multiple files or directories that may have been compressed. If you are not familiar with extracting content from ZIP files, see this Microsoft Support page for instructions.)

To create your own form in MS Word®  or MS Publisher®, simply download the building blocks you need. Then cut, paste, resize and move them around on the page to make a form that best fits your company’s needs. (Tip: Ask your children or grandchildren if you need help learning how to cut and paste. :-)

The generic PDF forms may be what you need, so you may choose to use them “as is.” 

If you need more ideas on what to include on your forms, see Section 2.17 in EASA’s Technical Manual located online in the EASA Resource Library.

Download the file using the link below.

Available Downloads

Creative method to remove blind pinion

Creative method to remove blind pinion

Ron Rapa
Rapa Electric, Inc.

At Rapa Electric, we’ve had a number of “opportunities” to remove a blind pinion from a motor shaft.

Sometimes, if we’re lucky, the pinion may have a push-off bolt to facilitate removal. And at other times, there may be a through-hole in the rotor shaft so that we can use a push-bar to shove the pinion out of its hole. If we’re not so lucky, we have to use a more creative method.

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Dealing with wet/flooded motors

Dealing with wet/flooded motors

Recovering from disaster: Saltwater becomes a major problem

Chuck Yung
EASA Senior Technical Support Specialist

Flooding in the aftermath of tropical storms (hurricanes, monsoons and cyclones) with heavy rainfall will often shut down hundreds of plants along the Gulf Coast from Florida to Texas and other places around the world.

To get them up and running again, maintenance departments and motor repairers face the daunting task of cleaning muck and moisture from many thousands of electric motors and generators. See Figure 1. The process in such situations can take weeks, if not months, and requires special clean-up procedures for motors contaminated by saltwater.

Although the problems are huge, affected plants can get back in production more quickly by working closely with service center professionals and following a few tips that will make the cleanup more manageable. These include prioritizing motors and generators for repair or replacement, storing contaminated machines properly, and using proven methods to flush away saltwater contamination. Constructing temporary ovens on site or at the service center can also add capacity for drying the insulation systems of flooded motors.

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De-reeling round magnet wire for best results

De-reeling round magnet wire for best results

Benny G. Darsey
Tampa Armmature Works, Inc.

There are several reasons that random wound electric motors have premature electrical failures. There have always been concerns of crossovers in the slot section and end turns. Crossovers create unfavorable conditions such as keeping the varnish or resin from bridging the magnet wires and bonding them together. Crossovers also create pressure points. Pressure points, combined with the condition of poor bridging of the varnish and the line frequency vibration, will cause the magnet wire insulation to abrade, causing a short circuit.

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Dos ejemplos de casos que indican la necesidad de tener cuidado con el metalizado

Dos ejemplos de casos que indican la necesidad de tener cuidado con el metalizado

Steve Skenzick
HPS Electrical Apparatus Sales & Service

En mi centro de servicio hemos visto problemas en ejes previamente reparados que fueron metalizados. En estos casos recibimos motores para revisión. Después de la inspección y de medir los ajustes de los rodamientos en el eje, encontramos algo que simplemente no se “sentía” bien. Podríamos decir por la apariencia que los ejes habían sido reparados antes de la revisión actual.

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Dynamometer and test stand considerations

Dynamometer and test stand considerations

Upfront analysis and planning can save time, money on purchase, installation

Kirk Kirkland
Electrical Repair Service Co.
Birmingham, Alabama
Technical Education Committee Member

Progressive end users/motor own­ers these days have a greater apprecia­tion for and understanding of motor reliability.

However, many no longer accept the premise that a quality rebuild is accomplished because experienced, well trained technicians serviced a motor and applied static and/or run testing which resulted in a motor with improved reliability. Many end users have developed stringent motor re­pair specifications to which the motor rebuilder must comply. 

More frequently, end users are requiring that the service center pro­vide proof of compliance. This often equates to a series of qualifying tests that may include having the service provider perform a load test on the serviced motor. The load test can be the “acid test” which validates that the repair services rendered meets with the end user’s specifications and/or the original manufacturer’s design criteria. Some end users are exposed to non-compliant issues when their driven equipment is the “load test.” 

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El cuidado y Uso de los Micrómetros

El cuidado y Uso de los Micrómetros

Frank Conci
Miembro del Comité Técnico de Servicios
A.C. Motor Electric, Ltd.

En este artículo trataremos los micrómetros exteriores. Sin embargo, las ideas y la información aplican a otros dispositivos de medición, tales como: Micrómetros de interiores, calibradores, transportadores, niveles, galgas de profundidad, etc.

En estos tiempos, la importancia de hacer mediciones precisas y exactas es más crítica que nunca. Nuestros clientes nos exigen cada vez más usar las mejores prácticas y obtener los mejores resultados posibles cuando efectuamos el mantenimiento y la reparación de sus máquinas, Para garantizar la disponibilidad de este servicio, EASA se encuentra a la vanguardia con su programa de certificación, normas técnicas y su soporte de ingeniería. Nuestros clientes esperan que los miembros de EASA utilicen instrumentos adecuados de una forma profesional y confiable al reparar y evaluar sus equipos.

El Efecto de la Reparación/Rebobinado en la Eficiencia del Motor

El Efecto de la Reparación/Rebobinado en la Eficiencia del Motor

EASA/AEMT Rewind study cover (Spanish)

El Efecto de la Reparación/Rebobinado en la Eficiencia del Motor: Estudio de rebobinado realizado por EASA/AEMT y la Guía de Buenas Prácticas, ilustran que cuando la reparación/rebobinado de un motor eléctrico se realiza de forma correcta, no se degrada su eficiencia! y que esta tampoco se reduce después de varios reparaciones/rebobinados.

Basado en un estudio realizado en conjunto por EASA y la Association of Electrical and Mechanical Trades (AEMT) del Reino Unido, esta publicación concluye que empleando las mejores prácticas de reparación/rebobinado la eficiencia del motor se conserva. Además de una Síntesis, el informe proporciona todos los datos de prueba, mucha información relacionada con procedimientos de prueba y metodología, información de los procedimientos que utilizan buenas prácticas, lecturas complementarias y un capítulo entero sobre las consideraciones para reparar/reemplazar un motor.

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Encourage (Proper) Use of Mobile Devices in the Service Center

Encourage (Proper) Use of Mobile Devices in the Service Center

Mike Howell
EASA Technical Support Specialist

There are plenty of generic mobile device policies floating around the web. Sadly, many of them focus heavily and narrowly on the disadvantages of team members having personal devices at their workstations. Depending on the particular environment and tools used, it is both reasonable and responsible to evaluate the potential risks to safety and security. Too often, though, organizations take the path of excluding mobile devices from the work area because it’s easy rather than reaping the benefits they offer.

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End Users Offer Perspective on Internet-Enabled Condition Monitoring

End Users Offer Perspective on Internet-Enabled Condition Monitoring

Paul Rossiter
Ad Hoc Committee on Emerging Technologies Member
Energy Management Corp.
Salt Lake City, Utah

In my Currents article last January, I discussed the newly formed Ad Hoc Committee on Emerging Technologies, chaired by Art Anderson, and mentioned that I thought there would be continued movement in the Industrial Internet of Things (IIoT) space. Specifically, I said I believed the discussion would increase around the IIoT topic, more companies would be coming into our space using this technology and that customers would begin to increase their adoption.

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Environmental Audit Questionnaire

Environmental Audit Questionnaire

Tom Barnes
Compliance Specialists, Inc.

This document will help you examine:

  • Facility general information
  • Document control
  • Facility audit history
  • Waste management, waste minimization, hazardous waste and waste reporting
  • Storm water
  • Spill prevention and reporting chemical inventory
  • New chemical acquisition
  • PCBs and asbestos
  • Underground storage tanks
  • Air emissions
  • Risk management plan
  • Employee training
  • Ozone depleting substances
  • Emergency planning

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Environmental update for EASA members in the U.S.

Environmental update for EASA members in the U.S.

Tom Barnes
Compliance Specialists,Inc.

As we enter a new and exciting year of operating EASA businesses, we must remember that almost all service centers in the U.S. with either dip or vacuum pressure impregnation (VPI) tanks will be subject to the SARA Title 3, Tier II, reporting requirements. This requirement is part of the Emergency Planning and Community Right to Know Act (EPCRA). The EPCRA involves notifying the state and local community of any hazardous chemical stored onsite in quantities over 10,000 lbs. A hazard material for the purpose of this regulation is anything hazardous under the Hazard Communication standard. In other words, if it has a Safety Data Sheet and you had more than 10,000 lbs onsite at any time during the previous year (2017), then you are subject to this reporting requirement.  For most EASA centers, this will include the VPI, the dip tank varnish, or, in some cases, both varnishes.

Other Tier II reporting
Additionally, EPCRA requires reporting of any Extremely Hazardous Substance (EHS) on the Tier II report if it exceeds either its Threshold Reporting Quantity (TPQ) or 500 lbs, whichever is less. Therefore, if you have electric forklifts (including walk-behind, pallet jacks), you must calculate the amount of sulfuric acid contained in those large batteries. If the total amount of sulfuric acid exceeds the 500 lbs threshold, then this must be reported on the Tier II reports. Note that an average 3,000-lb battery will contain about 450 lbs of sulfuric acid, so two or more lifts will require such reporting.

Must complete annually
Tier II reports must be completed annually and submitted each year by March 1st to the State Emergency Response Commission (SERC), the Local Emergency Planning Committee (LEPC) and to your local fire department.  As one service center recently found out during an ISO 14001 audit, failure to submit these reports could cost up to $20,000.  Failure to report these chemicals and experiencing an incident involving these chemicals could cost you your entire business, especially if someone was injured or killed in the incident.

Please note that these forms are quite simple to complete and, even though some states will have an annual cost associated with the filing of the reports (typically $100-$300), the cost will be minimal versus the consequences of not reporting. For assistance in determining if reporting is necessary and how to report, please check with your fellow EASA members or an environmental consultant.

Expand your capabilities: Start welding aluminum

Expand your capabilities: Start welding aluminum

Tips and techniques on how to become an expert with this material

Kent Henry 
Former EASA Technical Support Specialist

Editor's Note: Part 1 of this two-part series was published March 2010. Part 2 was published April 2010.

Suppose two motors came in for an emergency repair. One of the mo­tors is a steel frame and the other is an aluminum frame. Both have broken feet that need to be welded back on to frame. Which motor would you prefer to weld? I believe that most would choose steel over aluminum. But that doesn’t have to be the case.

Available Downloads

Features and benefits of EASA's Getting The Most From Your Electric Motors booklet

Features and benefits of EASA's Getting The Most From Your Electric Motors booklet

Tom Bishop, P.E.
EASA Senior Technical Support Specialist
​ EASA’s Getting The Most From Your Electric Motors is a great marketing tool for service centers to provide to customers (end users). As such, this valuable 40-page booklet provides end users with information that will help them obtain the longest, most efficient and cost-effective operation from general and definite purpose electric motors with these characteristics: 

  • Three-phase, squirrel-cage induction motors manufactured to NEMA MG1 standards 
  • Power ratings from 1 to 500 hp (1 to 375 kW) 
  • Speeds of 900 to 3600 rpm (8 to 2 poles) 
  • Voltages up to 1000V, 50/60 Hz 
  • All standard enclosures (i.e., DP, TEFC, WPI, WPII) 
  • Rolling element (ball and roller) and sleeve bearings

The following is an overview of the contents of the booklet indicating some of the ways that using it can benefit end users, i.e., your customers — and potential customers.

Installation, startup and baseline information
The first of the two major sections addresses three subtopics: motor installation, startup and baseline information. Early on it recommends making sure to document the motor’s initial condition to establish a baseline for comparison with future results. Among the benefits to the end user by following this practice is that it’s often possible to recognize small or developing problems before they lead to costly motor failures and downtime.

Reference is made to the “Motor and installation baseline data” sheet (see Figure 1) found in Appendix A. Recording the nameplate data and pertinent electrical and mechanical parameters at the time of installation and startup makes that information available for reference in hard copy or, if scanned, electronic format. Review of the motor data, including the nameplate information, can provide insight into the motor’s suitability for the application.

Specific items to check include motor suitability for use with a variable frequency drive (VFD), bearing suitability if the application is a belt drive, lubrication points accessibility, and verifying that the motor control and overload protections are sized properly for the motor rating. The last two points can be critical if the motor is a replacement and of a different power rating than the motor that it replaced.

Installation considerations such as the adequacy of the foundation and base are important for motor reliability. A weak or otherwise inadequate base can result in frame distortion, rapid bearing wear and vibration.

The booklet not only provides details on these topics, it extensively covers shaft alignment, including the issues of soft foot, alignment tolerances, and alignment methods for direct-coupled and for belt-drives. The end user can find a great deal of installation related information in just a few pages of the booklet.

The information in the booklet proceeds from the installation considerations to startup procedures. In many cases the motor being installed had been in storage; details are provided to help assure that the motor functions properly. Among the storage related topics are lubrication and the lubricant, and checking winding insulation resistance (see Table 1).

Next, recommendations are provided for pre-operation startup tests. Measuring and recording vibration levels is recommended. Recommended tests with the motor under load include line to line voltage, line currents, winding temperature (if possible), bearing temperature and ambient temperature. The booklet suggests these baseline values be recorded on the motor data sheet as a basis for future trending measurements. Two examples are provided to show the importance of recording baseline and trending data.

The section on motor installation, startup and baseline information concludes with the topic of total motor management. These programs typically track purchases and spares in a database by nameplate information, facility/location, and application. Usually they also track baseline data, maintenance, storage and repair. The primary benefits for the end users are that such programs lower costs by reducing downtime (spares are readily available) and decreasing inventory (identification of spares used in multiple locations).

A key consideration here is whether the most cost-effective and reliable solution is to store spare motors on site or to outsource storage to a service center or other vendor. Motor management and spare motor (and other equipment) storage is yet another opportunity for a service center to provide a value-added service for their customers. Further, having the customer’s spare motor at your facility provides a better opportunity to receive the replaced motor to perform the needed repairs.

Operational monitoring and maintenance
The second of the two major sections deals with operational monitoring and maintenance. Primary topics include application-specific conditions, preventive and predictive maintenance, inspection and testing, and bearing relubrication. By making use of the advice in this section the end user can extend the useful life of their motors, as well as the mean time between failures requiring repair.

Abnormalities in the electrical supply such as transient voltage can result in transient currents and torques which can damage not only windings but also mechanical components of the motor or driven equipment. To help the end user avoid these abnormalities, a bullet list identifies over a half-dozen potential sources. Another source of transient conditions that is not an abnormality is motor starting. The booklet provides the end user with guidance in dealing with motor starting and emphasizes the need to limit the number of motor starts.

The subsection on preventive maintenance (PM), predictive maintenance (PdM) and reliability-based (RBM) maintenance defines and describes each. Electrical and mechanical test and inspection techniques and physical condition assessments are identified for PM, PdM and RBM [also termed reliability-centered maintenance (RCM)]. Even if an end user already has a PM, PdM or RBM program, they can benefit from review of this subsection as it may identify missing elements in their program. Also, if an end user is not familiar with any of these programs the booklet provides information to get them started on the path to more reliable motor operation. That is, it provides an opportunity for the end user to get the most from their electric motors and probably the connected equipment as well.

Additional information on PM, PdM and RBM is included in the subsequent section on motor inspection and testing. All too often we hear the statement “don’t overlook the obvious.” That describes the importance of physical inspection in detecting missing, broken or damaged parts, blocked airflow paths and contaminants. Any one of these conditions could lead to premature and perhaps rapid motor failure.

Tests that are described in detail include insulation resistance, winding resistance and motor current signature analysis (see Table 2). When available from industry standards, criteria for evaluation are provided so that the end user can determine if their levels are acceptable or warrant corrective action. Cautionary information is provided regarding high-potential and surge testing of installed motors.  Information about vibration analysis using a spectrum analyzer is also provided.

This final subsection of the main body of the booklet provides guidance to help assure long and reliable motor operation. Recommendations include not only relubricating bearings, but also monitoring lubricant levels and checking for leaks and contamination. Guidance is provided to help the end user determine the correct relubrication interval and the lubricant type and grade when the motor manufacturer instructions are not available.

The importance of grease compatibility is stressed, and a grease incompatibility chart is provided.  Sage relubrication advice is given in the statement: “The best practice is to use the same grease that’s already in the bearings–provided it’s suitable for the application." A formula is provided to determine the precise amount of grease required; a graphic illustrates grease relubrication intervals based on bearing type, size and speed.

Oil-lubricated sleeve and rolling element bearing lubrication is also addressed, including topics such as oil compatibility, viscosity, and relubrication intervals.  Specific topics such as dealing with abnormal conditions and how to replace oil are also described.

Appendices
The three appendices provide supplementary information that can help the end user get more from their motors in terms of record-keeping, understanding motor terminology and storage. Appendix A contains a two-page data form (see Figure 1) intended for use in recording motor nameplate data and electrical and mechanical test data. Initially the data form can be used for baseline information, and then updated when maintenance or repairs are made. As such it can provide invaluable historical information for the end user and service firms when it becomes necessary to perform a simple failure analysis or more comprehensive root cause failure analysis.

The information in Appendix B is a compilation of key terms associated with motor nameplate data. (Note: There is also a standalone glossary at the end of the booklet.) However, the real value of this information is in determining the meaning of terms that at times are misunderstood. Knowing the true meaning and importance of these terms can help an end user avoid a costly and time-consuming mistake in purchasing a motor that is not suited for a specific application.

Based on member inquiries, motor storage recommendations, which are the topic of Appendix C, are a common end user request. These storage recommendations alone make the booklet a valuable resource for end users. The last page of this appendix summarizes how often to perform certain storage maintenance routines. It is rare to find this time versus task information all in one place, which is something many end users will appreciate.

Ordering information
Printed copies of Getting The Most From Your Electric Motors booklet can be purchased in EASA’s Online Store or you may download a PDF copy for FREE.

Imprinting available to EASA members
EASA members may also imprint their company name, logo or contact information on the cover of this booklet. This makes for an excellent marketing and educational tool to distribute to you customers. Download the imprinting guidelines and contact customer service to place you order.

 

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Fleet management: Ideas to help operate company vehicles more effectively and efficiently

Fleet management: Ideas to help operate company vehicles more effectively and efficiently

Mike Parsons
Hupp Electric Motor Co.

In any business, whether you have two pickup trucks or 50 semi-trucks, you have a fleet. This fleet is as much a part of your business as any other asset.

Your fleet is an expense and an investment, and managing it is essential. Any business that has a fleet of vehicles should take steps to keep that fleet functioning effectively and efficiently. The right policies, combined with the right technology, can make managing a vehicle fleet much easier on your company's time and budget.

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Fomente el Uso (Adecuado) de Dispositivos Móviles en el Centro de Servicio

Fomente el Uso (Adecuado) de Dispositivos Móviles en el Centro de Servicio

Por Mike Howell
Especialista de Soporte Técnico de EASA

Existen muchas políticas genéricas sobre el uso de los dispositivos móviles flotando en internet. Lamentablemente, muchas de ellas se centran en gran medida y de forma limitada en las desventajas de que los empleados tengan dispositivos personales en sus estaciones de trabajo. Dependiendo del entorno particular y de las herramientas utilizadas, es razonable y responsable evaluar los riesgos potenciales para la seguridad y la protección. Sin embargo, con mucha frecuencia, las organizaciones toman el camino de excluir los dispositivos móviles del área de trabajo porque es una medida fácil, en lugar de aprovechar los beneficios que ofrecen.

Guidelines for Maintaining Motor Efficiency During Rebuilding

Guidelines for Maintaining Motor Efficiency During Rebuilding

The challenge for every motor repair firm is twofold: to repair the equipment properly; and to demonstrate to their customers by means of adequate testing and documenta­tion that rewound motors retain their operating efficiency. Following the guidelines in the “DOs” and “DON’Ts” below will help you accomplish both.

Numerous studies have been done to determine the effect rewinding has on motor efficiency. These studies identified several variables that can impact the efficiency of a rewound motor, including core burnout temperature, winding design, bearing type, air gap and winding resistance. The following guidelines were developed as a result of those studies, which found that the efficiency of both standard and energy efficient electric motors can be maintained during rebuilding and rewinding. 

To ensure that motors retain their efficiencies when rewound, EASA also strongly recommends that electric motor repair centers comply with ANSI/EASA Standard AR100: Recommended Practice For The Repair Of Rotating Electrical Apparatus and strictly adhere to the “DOs” and “DON’Ts” that follow. These guidelines, which contain safe values (based on available data) and correct procedures, apply to both energy efficient and standard motors. Further study of the matter continues, and these guidelines will be revised if additional information warrants.

Available Downloads

Hazard Communication Manual

Hazard Communication Manual

This indispensable, FREE, 93-page manual was developed to help EASA service centers navigate the difficult terrain of the Federal OSHA Hazard Communication Standard. More specifically, it will help you collect and file Material Safety Data Sheets, train your employees, and document your training as required. Included are a summary of the OSHA Hazard Communication Standard, a compliance checklist, a suggested hazard communication program, hints on how to develop a written training program, and a primer on how to read Material Safety Data Sheets. The manual also contains a glossary and samples of various OSHA forms and letters.

Table of Contents

  • Introduction to Hazard Communication
    • Why was this standard put into effect?
    • How will this be done?
    • What should we be doing?
    • How can EASA service centers get this done?
    • Suppose we choose not to do anything?
    • Where can I get further information?
  • Section I: Summary Outline
    • Hazard communication
    • Hazard communication compliance checklist
  • Section II: Suggested Written Program
  • Section III: Hints on Developing Written Training
  • Section IV: How To Read & Understand MSDSs
  • Section V: MSDS Glossary
  • Section VI: Attachments
    • OSHA (Standard 1910.1200)
    • Checmical hazard communication
    • Voluntary training guidelines
    • Substance survey
    • Letters to manufacturers & suppliers
    • Letter re MSDSs to Seller
    • Followup letter re MSDSs to Seller
    • Chemical substance training record

Available Downloads

How to build a VPI system for your service center

How to build a VPI system for your service center

Jim McKee (deceased)
Alabama Electric Motor Service
Sheffield, Alabama 
Technical Education Committee Member 

There seems to be a long and never ending list of equipment and facilities needed by most EASA service centers. But often we are constrained by cost, available space, and more urgent priorities that keep us from fulfilling some of these needs. One such (almost mandatory) need is a vacuum pressure impregnation (VPI) system. 

Normally there are two ways to provide this service. One way is to have another EASA service center do the VPI process for you. Another is to buy your own system at a consider­able capital investment. 

There is also another option. We decided that the way to provide VPI processing was to build our own system. Most EASA service centers have a talented collection of people with numerous skills. Ours is no exception. We felt that we had the skills in house to do the job. All we needed was some hardware and to do a bit of research into how the process works. 

Available Downloads

How to Construct and Operate a Temporary Bake Oven

How to Construct and Operate a Temporary Bake Oven

This presentation demonstrates an easy-to-build temporary oven that can be constructed in the service center or in site. The recording covers:

  • Materials to use and where to obtain
  • Heating: electric, propane, or other?
  • Measuring winding temperature
  • Regulating oven temperature
  • Storage of the parts when not in use
  • Safety concerns and cautions

Target audience: This presentation will benefit service center supervisors and management.

How to strip an armature without degrading the core

How to strip an armature without degrading the core

A simple and efficient method to improve quality and save labor

Chuck Yung
EASA Senior Technical Support Specialist

We all know that stator cores should be burned at a controlled temperature to prevent lamination deterioration that can lead to harmful eddycurrent losses. But what about armatures? While that DC machine is energized by direct current, it is also true that the armature itself sees alternating current as the current in each coil reverses while passing from pole to pole. 

A temperature-controlled burnout oven permits us to cremate a stator without worry, but an armature is another story. Because the commutator is integral to the armature, and cannot be easily removed, some repairers resort to a hand-stripping operation. Careful use of a torch to warm the windings accelerates the stripping job, but controlling the core tempera­ture can be difficult. And stripping a large armature without heat is all but impossible by conventional methods. 

Available Downloads

How to supplement your available voltage supply

How to supplement your available voltage supply

Chuck Yung
EASA Technical Support Specialist 

When a service center’s test panel is designed with a limited number of incrementally stepped voltages, there are times when you need a voltage that is not available. In such cases, when you need a non-standard 3­phase voltage, one workaround is to use a 3-phase motor as an autotrans­former. This works to step down, or to step up, the available voltage. 

There are three key safety consid­erations here: 

  • Never energize part of a winding with more than the voltage that portion of the winding is subject to during normal operation. 
  • Do not exceed the voltage rating of the ground insulation. 
  • Select a motor that can handle the no-load current of the motor to be tested. 

Available Downloads

How To Wind Three-Phase Stators (Version 2)

How To Wind Three-Phase Stators (Version 2)

Self-paced, interactive training for stators 600 volts or less

This EASA software is a valuable interactive training tool ideal for training your novice(s). Even experienced winders will learn from it. The CD teaches how to wind in a richly detailed, step-by-step approach. It includes narrative, animations and video clips, with tests to assess student comprehension. The training, which is divided into 13 lessons, covers data taking, core testing, coil cutoff, burnout, stripping, core preparation, coil making, stator insulation, coil insertion, internal connections, lacing and bracing, inspection and test of untreated and treated windings, and winding treatment. Features include "Pro Tips" and "Drill Downs" that enhance the learning experience and assure that even the most experienced technician will learn from this product. The course is delivered as an interactive Adobe PDF file containing text, audio, video, supporting documents and quizzes.

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Important Considerations for Accommodating Pump Repair in Your Service Center

Important Considerations for Accommodating Pump Repair in Your Service Center

Gene Vogel
EASA Pump & Vibration Specialist

It happens to just about every EASA service center. A machine shows up for repair; it has leads, and there’s a motor, but the machine is a pump. Most often, it’s a close-coupled pump or a submersible pump. If your response is, “We don’t work on those here,” because you’re thinking, “We don’t know anything about repairing pumps,” you may be turning your back on some very profitable work.

As I detailed in my February Currents article, pump repair can be a very profitable expansion area for service centers that specialize in electric motor repair only. If you agree that pump repair would be a good fit for your business, the next step is to evaluate what changes your facility needs to accommodate repairing pumps. You will find that you have much of the necessary equipment from repairing electric motors. The mechanical characteristics of motors and centrifugal pumps are very similar. Depending on the type of pump, there may be very little additional that you need.

Available Downloads

Improving the Repair Process for Optimum Productivity

Improving the Repair Process for Optimum Productivity

Tom Bishop, P.E., and Chuck Yung
EASA Senior Technical Support Specialists

The typical service center repairs at least 300 motors per technician annually. Saving 8 minutes (0.133 hours) per job equates to: 300 x 0.133 = 40 man-hours per year—a full week of labor per employee. It is not unrealistic to expect twice that much savings, just by implementing some of these timesaving tips.

We all know that seemingly small time savings can significantly improve the bottom line. For a service center with a 12% return on investment (ROI), shaving a few minutes off each job is the equivalent of adding 2 manmonths of billing per productive employee.

For a 10-man service center, with a shop rate of $75 per hour, 20 man-months times 75 = $258,000. To add a quarter-million dollar account usually means adding personnel, sales maintenance, and risk of bad debt/warranty expense. However, steps that streamline efficiency continue to pay dividends.

Topics covered include:

  • Layout and workflow
  • Time killers
  • Time: Is every hour on the job billable?
  • Time-saving equipment
  • Attitude and productivity
  • Communicating effectively
  • Training
  • Lighting
  • Calibration
  • Storage/handling/procurement
  • Parts storage
  • Examples from real service centers

Available Downloads

Inexpensive pump test center provides value-added service

Inexpensive pump test center provides value-added service

Doug Moore
Kentucky Service Co., Inc.

Many EASA members perform service on pumps of some type and have had the customer return the pump or call back to say it leaks or it still will not pump. We solved this by making a very inexpensive test center for all types of pumps: flooded suction, immersion lube, submersible, centrifugal, deep well and many others.

Available Downloads

Infrared Thermography in the Service Center and in the Field

Infrared Thermography in the Service Center and in the Field

Cyndi Nyberg Esau
Former EASA Technical Support Specialist

In today’s economic climate, service centers look for opportunities to expand their services to their customers, and therefore profits. End users are also looking to reduce costs as well as downtime. Predictive and preventative maintenance has become increasingly important in industry.

Infrared thermography (IR) has traditionally been associated with inspection of switchgear and motor control centers (MCCs), a service that has become highly competitive. This paper will focus on niche opportunities for the service center – offering or using IR for more specialized services. 

Monitoring the condition of electric motor systems can detect problems that otherwise would not appear until a catastrophic failure occurs. By using thermography, abnormal heat sources that are invisible to the naked eye can be detected and remedied before a failure. This monitoring is not only limited to the motor. The motor system includes the driven equipment, MCC, cable runs, protective devices and the power supply. 

While IR will be the focus of this paper, there are other tests and technologies that will be necessary to complete the evaluation of a motor system. Although a thermal image may indicate that excessive temperatures are present, more information is usually necessary to fully assess a problem. Tools like vibration analysis, current signature, insulation resistance testing, and even visual inspection, all work in conjunction with thermography to paint a complete picture. 

The use of thermography is not limited to field service. The service center can employ this technology during the repair of rotating machinery. Applications include but are not limited to testing for open rotors and assessing the condition of stator and armature cores, windings, bearings and shop equipment.

 

Available Downloads

Instruments and tools for testing brushless servo motors

Instruments and tools for testing brushless servo motors

Luther (Red) Norris 
Quality Solutions Co. LLC 
Greenwood, Indiana 
Technical Services Committee Member
 
Brushless servo motors ARE electric motors; therefore many of the tools needed to test them are already available in an electric motor service center. In this article, I have listed some instruments and tools that will be needed to service servo motors.

For the purpose of simplifying the instruments and tools needed for brushless servo motor repair, I am going to break them into two groups. 

  • Group 1—those usually found in an electric motor service center.
  • Group 2—those that may not usually be found in an electric motor service center. 

Available Downloads

Lean: Improve Your Shop Efficiency and Productivity

Lean: Improve Your Shop Efficiency and Productivity

Introduction to 5S

This recording will help you get organized using the “5+1 S Series.”

The “5S” program covers these goals:

  • Sort
  • Straighten
  • Shine
  • Standardize
  • Sustain

The additional “S” has been added by EASA and covers safety.

Starting in February 2019, members of the Management Services Committee will also write Currents articles on how each “S” can help you with a path to productivity by becoming more efficient, or lean.

Available Downloads

Lidiando con motores mojados o inundados

Lidiando con motores mojados o inundados

Recuperándose del desastre: El agua salada se convierte en el mayor problema

Chuck Yung
Especialista Sénior de Soporte Técnico de EASA

A menudo, las inundaciones producidas por las intensas lluvias de las tormentas tropicales (huracanes, monzones y ciclones) colapsan cientos de plantas industriales a todo lo largo de la costa del golfo de México, desde la Florida hasta Texas y en otros lugares del mundo.

Para retomar las actividades productivas, los departamentos de mantenimiento y los reparadores enfrentan la difícil tarea de limpiar la suciedad y desalojar la humedad en miles de motores y generadores eléctricos. Ver Figura 1. El proceso en tales situaciones puede tomar semanas o meses y requiere procedimientos especiales para limpiar los motores contaminados con agua salada.

Aunque el problema es enorme, las fábricas pueden volver a producir más rápidamente aunando esfuerzos con centros de servicio profesionales y siguiendo algunos consejos que facilitan las tareas de limpieza. Estos incluyen, priorizar los motores que requieren ser reparados o reemplazados, almacenar adecuadamente las máquinas contaminadas y utilizar métodos contrastados para eliminar la contaminación con agua salada. Fabricar hornos provisionales in situ o en el centro de servicio también puede aumentar la capacidad de secado de los sistemas de aislamiento de los motores inundados.

Available Downloads

Los Ambientes Controlados y los Cuartos Limpios Previenen la Contaminación en los Centros de Servicio

Los Ambientes Controlados y los Cuartos Limpios Previenen la Contaminación en los Centros de Servicio

Tom Bishop, P.E.
Especialista Sénior de Soporte Técnico

De vez en cuando escuchamos el término “cuarto limpio” para nombrar un área de bobinado aislada físicamente de las demás zonas del centro de servicio (Figura 1). La finalidad principal de tal encerramiento (Figura 2) es prevenir que los materiales y los bobinados se contaminen con polvo y suciedad que pueda estar presente en otros sitios del centro de servicio. Algunos centros de servicio construyen estos encerramientos porque se esfuerzan en proporcionar el ambiente práctico más limpio para los trabajos de rebobinado y otros los usan también durante el proceso de instalación de los rodamientos. Los recintos tipo cuarto limpio también pueden beneficiar a las instalaciones ayudando a minimizar problemas de calidad y aumentando el volumen de producto conforme.

Aquí, exploraremos la diferencia entre un ambiente controlado y un cuarto limpio, los requisitos para ambos y proporcionaremos detalles para ayudarle a determinar si quiere añadir a sus instalaciones un ambiente controlado o un cuarto limpio.

Available Downloads

Los programas AC Motor Verification and Redesign y Motor Rewind Data Version 4 trabajan en conjunto para ofrecer más funciones

Los programas AC Motor Verification and Redesign y Motor Rewind Data Version 4 trabajan en conjunto para ofrecer más funciones

Gene Vogel
Especialista de Bombas y Vibraciones de EASA

Las nuevas funciones del programa AC Motor Verification and Redesign – Version 4 (ACRewind) de EASA mejoran la capacidad de los miembros de EASA para enviar datos originales de forma electrónica e incluirlos en la base de datos Motor Rewind Data – Version 4 (MotorDB). Pase directamente a la sección “mejoras” si ya está familiarizado con los programas y cómo funcionan.

El software de la Version 4 es un conjunto de herramientas poderosas que sirve para que los miembros de EASA validen los datos de un bobinado, rediseñen devanados concéntricos a imbricados y efectúen cambios en los parámetros de un motor. Una característica clave de esta última versión del programa es la integración de la base de datos MotorDB con el programa ACRewind. La disponibilidad de ambas funciones del programa dentro de una interfaz de usuario común no es por simple conveniencia. La capacidad de los programas para compartir las fuentes de datos crea nuevas capacidades que la versión de cada programa independiente no podría.

Measurement Best Practices for Troubleshooting Motors and Drives

Measurement Best Practices for Troubleshooting Motors and Drives

Adam Willwerth (deceased)
AEGIS, Electro Static Technology, Mechanic Falls, ME
and
Hilton Hammond
Fluke Corporation, Everett, WA

Get a better understanding of the working principles of motor and drive measurements with test equipment, analysis tools and best practices. This paper presents valuable services you can incorporate to increase services and profits. It also covers:

  • Safety practices related to test equipment
  • Overview of the system drive train covering measurement protocols for:
    • Drive input and output
    • Motor and drive
    • Shaft voltage measurement and assessment

Not only is the measurement protocol explained but also the technology behind the systems under discussion, such as the inverter and motor. Measuring devices discussed will include:

  • ScopeMeter
  • Shaft voltage test kit
  • Vibration analyzer
  • Insulation tester
  • Thermal imager

Available Downloads

Mechanical Repair Fundamentals of Electric Motors (2nd Edition)

Mechanical Repair Fundamentals of Electric Motors (2nd Edition)

Mechanical Repair Fundamentals coverFundamental to every good mechanical repair is the ability to disassemble, repair and reassemble the motor correctly without unnecessary damage to any of the motor parts. This sounds simple, and yet too many costly mistakes are made in this process of taking things apart. If every motor repaired was in “as new” condition, the task would be much simpler. But this would be no guarantee that the reassembly would be correct.

​There is usually an easy way and a hard way to remove and install parts. Brute force is seldom the easiest or the correct way. The old saying of “don’t force it, get a bigger hammer” is seldom the best way.

When a service center is paid to repair equipment, the service center wants it to stay in operation. If the equipment fails again—within the warranty period—the service center pays to repair it again. It makes sense to repair it correctly the first time.

In order to improve equipment, it is important to know how and where it operates. Without understanding why a motor fails, it is impossible to deliberately improve its mean time between failures.

To do this, there must be communication between the service center and the motor user. Not only does this help the repairer decide the best course of action, but it helps the user appreciate the professionalism of the service center.

Repair procedures, like motors themselves, are affected by changes in technology. This book attempts to include the latest proven technologies. Time-honored methods of repair, in many cases, may still be the most practical option. Options presented throughout this book are intended to help the technician select the appropriate repair method, recognizing that the ultimate decision rests with the equipment owner.

Repair methods sometimes fall into disfavor, not because better methods are introduced, but because of poor techniques. Other repair methods are well-suited to some applications but not to others. It is the job of the repairer to decide what is the best method for each case.

This book is divided into sections for basic motor components with repair methods and tips dispersed throughout. Where practical, reasons for failures are also discussed. These will aid the technician in selecting the most appropriate method of repair for each unique application.

The information presented draws from EASA publications, IEEE publications, technical journals and literature supplied by vendors, motor manufacturers and established service centers.

This book contains many suggestions on how to correctly handle the various parts of a motor during the repair process so as to minimize damage. However, it is impossible to develop an all-inclusive list. Instead, the basic principle of taking the time to use the correct tool and correct procedure will usually lead the technician down the right path. Always remember, if it has to be forced beyond reason, it might be that neither the proper tool or procedure is being used or something is wrong with the parts. Step back and ask “What am I overlooking?”

Table of Contents

  1. Motor Nomenclature
  2. Motor Applications and Enclosures
  3. Test and Inspection Procedures
  4. Motor Disassembly Tips
  5. Bearings
  6. Bearing Housing Repair, Shaft Openings, Seals and Fits
  7. Shafts
  8. Rotors
  9. Motor Assembly
  10. Motor Accessories and Terminal Boxes
  11. Motor Dynamics
  12. Vibration and Motor Geometry
  13. Shaft/Bearing Currents
  14. Special Considerations for Explosion-Proof Motors
  15. Failures in Mechanical Components
  16. Miscellaneous Repairs

This book is available as part of EASA's Fundamentals of Mechanical Repair seminar.

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Members find that digital cameras focus on productivity, practicality

Members find that digital cameras focus on productivity, practicality

Chuck Yung    
EASA Technical Support Specialist    

Of all the new technology available to EASA members, one of the most visible is the digital camera. Members from around the globe used them to record specific pieces of equipment for future orders.

More progressive service centers use them to enhance repair reports to increase customer satisfaction. An embedded photograph of an unusual failure adds value for the customer. It also confirms the professionalism of the service center. Large repairs justify a comprehensive repair report, with photos documenting the repair procedures as well as the failure analysis. Electronically transmitted digital photos can save customers a round-trip that is often necessary to inspect a machinery failure.

Available Downloads

Minimizing Calibration Costs

Minimizing Calibration Costs

This webinar covers :

  • Quantities/qualities of measuring and test equipment utilized in the industry
  • How to locate/source qualified calibration suppliers
  • Costs of internal / external calibration for some measuring and test equipment

Motor Rewind Data - Ver. 4

Motor Rewind Data - Ver. 4

This valuable resource is available only to EASA Members.

Active and Allied members can download this software for FREE!

This version of the EASA Motor Rewind Database software takes a large leap forward with the data that it provides members. Most notably, it now has the ability to connect to a live, ever-expanding online database of more than 250,000 windings. This live database will be continuously monitored, updated and corrected as needed by EASA’s Technical Support Staff. Using the online database guarantees you’ll have the most up-to-date information available at all times. If your computer does not have an Internet connection, the software will automatically switch to the static, local database that was included and loaded during installation. (Note: The local database does not receive updates.)

The database includes:

  • Three-phase, single-speed AC motors
  • Three-phase, multi-speed AC motors
  • Single-phase AC motors
  • DC motors & generators

Power supply considerations when building a large growler

Power supply considerations when building a large growler

Tom Bishop
EASA Senior Technical Support Specialist

When considering building a large growler for testing armatures and rotors, the initial decision typically is to select a kVA rating. A primary reason for this is that the growler will need to be connected to a power supply of sufficient ampacity at the supply voltage. To help simplify a complex design process, four kVA ratings have been selected for this article. One of the selected ratings should fit the needs of most service centers.

This article covers:

  • A design example
  • Determining turns and wire size
  • Building the core
  • Determining coil dimensions

Available Downloads

Procedure helps remove uncertainty from drying time for windings

Procedure helps remove uncertainty from drying time for windings

Chuck Yung 
EASA Technical Support Specialist 

We've all faced those rush jobs, where a cus­tomer is desperate to get his motor back faster than humanly possible. It is our nature to try to do the impossible that's why we are in this business.

We enjoy a challenge and the opportunity to help people. Turning a motor around quickly, when a customer is in need, is rewarding. One of the most time-consuming steps drying the windings after they have been cleaned Ð can be frustratingly slow when an anxious customer is calling. How long does that motor need to bake to be safe? 

Most service centers have built in a safety factor, based on some long-forgotten problem we had (or heard about) with a winding that was not properly dried. "Joe" opened the oven door right before lunch and left it open, then someone pulled a stator out a couple of hours later and it megged low. Maybe it failed on the test panel. Of course, "Joe" didn't fess up to what happened.  So you told everyone: "From now on, all windings bake 2 hours longer than we used to."

Available Downloads

Projectos simplificados por una mejor comprensión de los ratios y proporciones

Projectos simplificados por una mejor comprensión de los ratios y proporciones

Gene Vogel
EASA Pump & Vibration Specialist

Si un tercio de dólar es 33.33 centavos, entonces ¿Cuanto sería la tercera parte de un dólar y medio? Si usted se encuentra sumando 33.33 centavos con 16.66 centavos antes de darse cuenta que un tercio de $1.50 es $ 0.50, obviamente usted sufre un caso serio de “Calculitis” Afortunadamente, la cura es una dosis de ratios y proporciones.

La terminología técnica para los ratios es “números racionales”, números que literalmente son ratios. La capacidad de trabajar con números racionales es una herramienta poderosa para evaluar opciones, calcular resultados y representar valores. Este artículo es una introducción de algunos conceptos básicos y un estudio más profundo revelará características fascinantes y la parte íntima que juegan en las matemáticas, las ciencias y en cada aspecto tecnológico.

Available Downloads

Projects simplified with better understanding of ratios and proportions

Projects simplified with better understanding of ratios and proportions

Gene Vogel
EASA Pump & Vibration Specialist

If a third of a dollar is 33.33 cents, what is a third of dollar and a half? If you find yourself adding 33.33 cents to 16.66 cents before you realize that obviously a third of $1.50 is $ 0.50, you have a serious case of “calculatoritis.” Fortunately, the cure is a healthy dose of ratios and proportions.

The technical term for ratios is “rational numbers,” literally numbers that are ratios. The ability to work with rational numbers is a powerful tool for evaluating options, calculating results and representing values. This article is an introduction of some basics; a more in depth study will reveal fascinating characteristics and the intimate part they play in math, science and every aspect of technology.

 

Available Downloads

Proper Motor Cleaning: Avoiding Damage to the Motor and the Environment

Proper Motor Cleaning: Avoiding Damage to the Motor and the Environment

This presentation examines features, benefits and drawbacks of both conventional and alternative methods of cleaning electric motors.

Methods covered include:

  • Immersion tanks
  • Steam cleaning
  • Parts-washing machines
  • Pressure washers
  • Abrasives
  • Ultrasonic devices

Environmental options for handling waste by-products are also addressed. If you are considering changing your cleaning methods, this webinar is for you.

Proper use of the core tester

Proper use of the core tester

Tom Bishop, P.E.
EASA Technical Support Specialist
 
Prior to rewinding it is advisable to assess the condition of the core iron of stators, armatures and wound rotors. The assessment is performed by a core test, which magnetizes the core to a pre­scribed magnetic flux density. The predominant tests used to determine core condition are the hot spot test and the core loss watts test. The hot spot test compares the hottest spot in the core to either ambient temperature or core average temperature. The watts loss test compares the core loss test watts prior to winding removal to the same test af­ter the windings have been removed and the core prepared for rewind. 

Core testing traditionally was performed by the use of the loop (ring) test. That required multiple turns of wire to be passed through a core in order to magnetize the core and test for shorted laminations. Mag­netic strength is related to the ampere-turns (amperes x turns) of the magnetizing coil. Mod­ern core testers make it possible to test a core with a single turn of wire, by using high current. Thus the core tester uses one turn and many amperes, whereas the loop test typically uses many turns and a relatively low current. 

Available Downloads

Prueba simple para comprobar si un encoder es funcional

Prueba simple para comprobar si un encoder es funcional

Pat Douglas
Kirby Risk-Mechanical Solutions & Service

Un encoder es un tipo de dispositivo de retroalimentación que a menudo se instala en un motor para monitorizar el movimiento (óptico sencillo). Un encoder de cuadratura indica tanto el movimiento como la dirección del eje de salida del motor.

La Figura 1 muestra una forma de onda digital buena y la Figura 2 una forma de onda digital con ruido. Ambas han sido escaneadas desde un osciloscopio utilizado en un centro de servicio.

Available Downloads

Purpose built tools for the service center

Purpose built tools for the service center

Jasper Fisher 
Rexel Motor Repair 
Alton, Illinois 
Technical Education Committee Member 

Though it is unlikely a typical EASA member firm can achieve OEM (Original Equipment Manufacturer) economies of scale, we can strive to improve safety and working conditions, improve quality and increase labor efficiency thereby enhancing earnings. 

This article shares tips for building several special tools and fixtures, and it identifies one commercially avail­able tool to help us achieve safety and quality goals while improving our productivity. 
After hearing complaints about the purchase cost for the last two sets of custom heat-treated long taper pinion removal wedges, our ma­chine shop staff designed and built a fixture for tapering “brake die” rectangular steel (Figure 1).

Available Downloads

Repair Best Practices to Maintain Efficiency

Repair Best Practices to Maintain Efficiency

There are certain repair processes, such as winding removal and replacement, that can impact the efficiency and reliability of electric motors. Prudent repair practices must not increase overall losses, and preferably should maintain or reduce them.

This presentation explains how those repair processes affect efficiency and reliability, and gives the best repair practices in order to maintain or improve efficiency.

Target audience: This presentation is most useful for service center inside and outside sales representatives, customer service personnel, engineers, supervisors and managers. The content will be beneficial for beginners through highly experienced persons.

Rewind 2021

Rewind 2021

Recordings and Handouts from the 2021 EASA Convention - Fort Worth, TX

Revisit EASA's 2021 Convention & Solutions Expo by buying access to recordings of the general sessions and education events streamed from EASA's website!

These recordings provide just over 22 hours of training. Downloadable PDFs of slides and technical papers are included!

Technical presentations include:

  • Overview, Operation, Troubleshooting, Testing & Repair of Synchronous Motors - Javier Portos, Integrated Power Services, LLC, La Porte, TX
  • Understanding Corrosion in Pumps - Gene Vogel, EASA Pump & Vibration Specialist
  • Tips & Tricks for Submersible Pump Repair - Gene Vogel, EASA Pump & Vibration Specialist
  • Proper Field Installation of Vertical Turbine Pump Motors - Gene Vogel, EASA Pump & Vibration Specialist
  • Carbon Brush Applications, Tip & Tricks - Matthew Conville, EASA Technical Support Specialist
  • Generator Repair Tips - Wayne Hall, Jenkins Electric, Charlotte, NC
  • Repair Best Practices to Maintain Motor Efficiency & Reliability - Tom Bishop, P.E., EASA Senior Technical Support Specialist
  • Failure Modes, Troubleshooting & Maintenance Best Practices - Calvin Earp & Ron Widup, Shermco Industries, Irving, TX
  • Estimating Performance of Small Induction Motors Without a Dyno - Mike Howell, EASA Technical Support Specialist
  • Use the Latest Tools of the Trade for Field Testing of Electric Motors - Calvin Earp & Ron Widup, Shermco Industries, Irving, TX

En Español

  • Construcción del Estator (de Principios de Motores C.A. Medianos y Grandes) - Carlos Ramirez, EASA Especialista de Soporte Técnico
  • Lo Qué Necesita Saber para Comprar, Instalar, Operar & Reparar Motores Eléctricos - Carlos Ramriez, Especialista de Soporte Técnico de EASA

Sales presentations include:

  • 5 Fundamentals for a Successful Sales Attack! - Mike Weinberg Speaker, Consultant, Best-Selling Author
  • Getting The Meeting - Mike Weinberg Speaker, Consultant, Best-Selling Author
  • Every Sales YES Begins with a KNOW - Sam Richter, SBR Worldwide, LLC, Minnetonka, MN

Management presentations include:

  • EASA Research on Growing Your Business: Key Info from the Manufacturer/Supplier Community - Jerry Peerbolte, J. Peerbolte & Associates, Fort Smith, AR
  • EASA 2021 and Beyond - Brian Beaulieu, ITR Economics, Manchester, NH
  • Global Update: Marketplace Trends on Motor-Driven Systems (and IIoT) - Ivan Campos, Analyst, Manufacturing Technology, OMDIA (formerly IHS Markit)
  • Engaged Leadership - Clint Swindall, Verbalocity, Inc., San Antonio, TX
  • Connecting Generations - Clint Swindall, Verbalocity, Inc., San Antonio, TX
  • Optimizing Service Center & Management Efficiency - Chuck Yung, EASA Senior Technical Support Specialist

How do I access this content?
After purchasing, you can access the streaming content by going to the Convention or Training menus at easa.com and looking for "Past Convention Presentations" ... or you may go to https://easa.com/convention/past-convention-presentations/easa-rewind-2021.

NOTE: Access to the streaming content will be granted only to the person making the purchase.


 

Safety Cautions You Can't Afford to Miss

Safety Cautions You Can't Afford to Miss

Ron Widup
Shermco Industries
Irving, TX

Learn from an industry veteran about safety topics you may think you know but that can cost your firm substantially if you’re not diligent.

  • Fall protection
  • Fork lift hazards and relevant regulations
  • Material handling/lifting
  • Cranes and hoists
  • Machine shop hazards
  • Cautions regarding abrasive blasting
  • Painting irritants

Available Downloads

Safety Concerns: Electrical Safety, Lockout/Tagout, Arc Flash

Safety Concerns: Electrical Safety, Lockout/Tagout, Arc Flash

Industry expert Tom Barnes of Compliance Specialists, Inc. focuses on electrical safety, arc flash and lockout/tagout – defining the regulations for each and what your service center needs to do to protect your workers AND your pocketbook.

Available Downloads

Safety Module #1: Personal protective equipment (PPE)

Safety Module #1: Personal protective equipment (PPE)

Safety Module 1Purpose of the PPE Module To develop a written procedure that clearly defines the organization’s goal of determining what hazards exist at the facility and to assist the facility in either eliminating, if possible, or minimizing the hazards where they cannot be eliminated. This will be completed by identifying potential hazards, understanding and implementing the hierarchy of controls and, when necessary, selecting the proper PPE to be utilized, providing such PPE whenever necessary, and teaching affected personnel in the proper use and maintenance and care of the PPE selected.

The organization has three main objectives it wishes to accomplish in regard to its PPE program:

  • To protect its employees against injuries incurred at the facility
  • To protect the organization’s employees against both short-term and long-term illnesses relating to chemical exposures, noise exposure, injurious light radiation, temperature variations and other related hazards.
  • To protect the organization against the legal exposure created by allowing and/or requiring its human resources to be exposed (noted in the first two goals)

BUY THE WEBINAR RECORDINGS
(Both Management & Employee presentations are included)

Available Downloads

Safety Module #10: Machine guarding, hand tools

Safety Module #10: Machine guarding, hand tools

Safety Module 10Thousands of workers are injured every year due to non-existent, or improperly installed machine guards. Death, serious injury, crushed hands and arms, severed fingers, blindness and a host of other types of injuries can be the result of improper machine guarding. The Occupational Safety and Health Administration (OSHA) estimates that most of these accidents can be prevented if proper safety precautions at job sites are initiated. This poses a serious problem for exposed workers and their employer. The OSHA Machine Guarding Standards establishes uniform requirements to ensure that the hazards of non-existent or improper machine guarding in U.S. workplaces are evaluated, safety procedures implemented, and that the proper hazard information is transmitted to all affected workers.

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(Both Management & Employee presentations are included)

Available Downloads

Safety Module #11: Respirator program

Safety Module #11: Respirator program

Safety Module 11Millions of workers are potentially exposed to one or more chemical hazards on a daily basis. There are an estimated 575,000 existing chemical products; hundreds of new ones are introduced annually. In the U.S., the Occupational Safety and Health Administration (OSHA) establishes uniform requirements to make sure that the respiratory hazards of workplaces are evaluated and that engineering and work practice controls are implemented along with a respiratory protection program.

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(Both Management & Employee presentations are included)

Available Downloads

Safety Module #12: Welding, hot work, compressed gasses

Safety Module #12: Welding, hot work, compressed gasses

The welding, cutting and brazing processes expose workers to a variety of hazards including: burns, fire, eye damage, possible lung irritation and damage, electric shock, slips and falls. Numerous injuries and deaths occur each year from the hazards associated with welding, cutting and brazing operations in the American workplace. Most of these injuries and deaths are preventable.

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(Both Management & Employee presentations are included)

Available Downloads

Safety Module #16: DOT, hazardous material shipping

Safety Module #16: DOT, hazardous material shipping

Tom Barnes
Compliance Specialists, Inc.

The purpose of the DOT, Hazardous Material Shipping module is to assist service center personnel in the important rules and regulations related to the safe transportation of hazardous materials. Among the documents included are tests; a hazmat training brochure; an emergency response guidebook; a guide for hazardous materials marking, labeling and placarding; frequently asked questions related to hazmat training; a brochure on how to use hazardous materials regulations; and a loading and unloading certificate of completion.

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(Both Management & Employee presentations are included)

Safety Module #3: Cranes and slings

Safety Module #3: Cranes and slings

Safety Module 3Studies have shown that more than 25% of all occupational injuries are related to material handling. These injuries not only bring hardships to the employees injured and to their families, but the impact on productivity and profitability can be tremendous. The operation of cranes and slings have been responsible for incidents involving death, serious injury, damage to buildings, damage to stock, and damage to the forklifts themselves.  Since considerable risk is involved in the use of cranes and slings, OSHA has required that all workers using these types of trucks be properly trained in the use and maintenance of such equipment.

BUY THE WEBINAR RECORDINGS
(Both Management & Employee presentations are included)

Available Downloads

Safety Module #4: Lockout/Tagout

Safety Module #4: Lockout/Tagout

Safety Module 4Approximately three million workers in the United States on a daily basis, face extreme risk from uncontrolled energy when servicing machinery.  Serious injury or death can be the result. Typical non-lethal injuries include fractures, lacerations, contusions, amputations, puncture wounds, electric shock, and falls. The average lost time for injuries runs approximately 24 days. The Occupational Safety and Health Administration (OSHA) estimates that approximately 120 fatalities and approximately 28,000 serious and 32,000 minor injuries each could be prevented if proper lockout/tagout procedures at job sites are initiated. This poses a serious problem for exposed workers and their employer. The OSHA Control of Hazardous Energy Sources Standard establishes uniform requirements to ensure that the hazards of uncontrolled energy in U.S. workplaces are evaluated, safety procedures implemented, and that the proper hazard information is transmitted to all affected workers.

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(Both Management & Employee presentations are included)

Available Downloads

Safety Module #5: Fall protection

Safety Module #5: Fall protection

Safety Module 5Thousands of workers are injured every year due to slips, trips, or falls generated by improper walking and working surfaces. This poses a serious problem for exposed workers and their employers. The Occupational Safety and Health Administration (OSHA) estimates that most of these accidents can be prevented if proper safety precautions at job sites are initiated. The OSHA Walking and Working Standards establish uniform requirements to ensure that the associated hazards in U.S. workplaces are evaluated, safety procedures implemented, and that the proper hazard information is transmitted to all affected workers.

BUY THE WEBINAR RECORDINGS
(Both Management & Employee presentations are included)

Available Downloads

Safety Module #7: Industrial lift trucks

Safety Module #7: Industrial lift trucks

Safety Module 7Studies have shown that more than 25% of all occupational injuries are related to material handling. These injuries not only bring hardships to the employees injured and to their families, but the impact on productivity and profitability can be tremendous. The operation of industrial lift trucks has been responsible for incidents involving death, serious injury, damage to buildings, damage to stock, and damage to the forklifts themselves. Since considerable risk is involved in the use of industrial lift trucks, OSHA has required that all workers using these types of trucks be properly trained in the use and maintenance of such equipment.

BUY THE WEBINAR RECORDINGS
(Both Management & Employee presentations are included)

Available Downloads

Safety Module #9: Fire prevention, emergency preparedness program

Safety Module #9: Fire prevention, emergency preparedness program

Safety Module 9This safety module will help companies identify and prepare for potential fire hazards. This fire prevention, emergency preparedness program is intended to address comprehensively the issues of: evaluating and identifying potential fire hazards, providing proper exits, fire fighting equipment, along with emergency plans for inclement weather, bomb threats, medical emergencies, and chemical spills. Written procedures and communication of information concerning these hazards to employees are also addressed as part of this plan.

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(Both Management & Employee presentations are included)

Available Downloads

Safety: What is unique about an electric motor service facility?

Safety: What is unique about an electric motor service facility?

Chuck Yung
EASA Senior Technical Support Specialist

As anyone who is familiar with insurance inspectors, the U.S. Occupational Safety and Health Administration (OSHA) and other regulatory bodies knows, there are rather unique dangers in the electromechanical repair industry. Balancing machines and test panels are high on the list.

Both require easy access – and both pose significant risk to personnel. In most circumstances, unguarded rotating machinery and temporary electrical connections are cause for great concern.

Available Downloads

Seguridad: ¿Qué tiene de especial un centro de servicio de motores eléctricos?

Seguridad: ¿Qué tiene de especial un centro de servicio de motores eléctricos?

Chuck Yung
EASA Senior Technical Support Specialist

Como cualquiera que esté familiarizado con inspectores de seguridad, la Administración de Salud y Seguridad Ocupacional de los Estados Unidos (OSHA) y otros entes reguladores conocidos, existen peligros únicos en la industria de reparación electro-mecánica. Las máquinas balanceadoras y los tableros de prueba ocupan un lugar destacado dentro de la lista.

Ambos requieren fácil acceso e implican un riesgo importante para el personal. En la mayoría de los casos, la maquinaria rotativa sin guardas de protección y las conexiones eléctricas temporales son motivo de gran preocupación.

Available Downloads

Selección y uso de un Variador de Frecuencia Electrónico para hacer pruebas en un centro de servicios

Selección y uso de un Variador de Frecuencia Electrónico para hacer pruebas en un centro de servicios

Con el aumento de la popularidad de los variadores de frecuencia electrónicos (VFDs o drives), es probable que casi todos los centros de servicio miembros de EASA hayan reparado algún motor que funcione con un variador de frecuencia en las instalaciones de un cliente. Lo más conveniente después de reparar estos motores es probarlos, generalmente en vacio, utilizando un drive. Esto nos permite simular la aplicación real del cliente variando la velocidad así como también tener la certeza que el motor funciona bien mecánicamente dentro de un rango de velocidades. Esto incluye descubrir problemas de vibraciones, identificar alguna velocidad de resonancia dentro del rango de operación y otros problemas. Además, si el motor está trabajando por arriba de la frecuencia de red (ej. 50 ó 60 Hz), deberá funcionar hasta alcanzar su velocidad máxima para comprobar sus niveles de vibración y que los rodamientos puedan expulsar el exceso de lubricación y se asienten por sí mismos en su posición de trabajo (break-in).

Los temas cubiertos incluyen:

  • desafíos de selección
  • Tensión, potencia y frecuencia
  • VFD nuevos o usados para las pruebas?
  • Parámetros de operación

Available Downloads

Selection and use of a VFD for service center testing

Selection and use of a VFD for service center testing

Art Godfrey (retired)
Birclar Electric & Electronics
Romulus, Michigan
Technical Services Committee Member

With the growing popularity of variable frequency drives (VFDs), it is likely almost every EASA service center has repaired motors powered by one in a customer’s installation. For these motors, it is best that after repair they are tested using a VFD, typically at no-load. This will provide operation mimicking the actual customer applica­tion, at varying speeds, and will help ensure proper mechanical operation throughout the speed range. This will include detecting vibration problems, identifying any resonant speeds within the operating range, and more. Also, if the motor is used above utility line fre­quency (i.e., 50 Hz or 60 Hz), it should be operated up to top speed for vibra­tion measurement and a good break-in of the bearings.

Available Downloads

Service center hazards: Training, preparation and best practices to avoid risks, danger, accidents

Service center hazards: Training, preparation and best practices to avoid risks, danger, accidents

Kent Henry 
EASA Technical Support Specialist 

To repair electrical apparatus, obviously we need to use certain spe­cialized machinery. These machines have some common safety hazards as well as unique potential dangers. This article will review a few of the more common machines and their safety risks with examples of how to address them. The main objective is to get everyone to stop, take a step back, and find ways to address potential safety issues. 

If questioned, most experienced machine operators could quickly point out the dangers of a certain machine he or she uses. For some hazards, safety devices are not available. The only protection is knowing the danger points and training your staff to stay clear of dangerous areas. 

Available Downloads

Simple test to show if encoder is functional

Simple test to show if encoder is functional

Pat Douglas
Kirby Risk-Mechanical Solutions & Service

An encoder is a type of feedback device that is often installed on a motor to monitor the motion (simple optical). A quadrature encoder indicates both motion and direction of the motor output shaft. 

Figure 1 indicates a good digital waveform.  Figure 2 indicates a noisy digital waveform. Both are scans from an oscilloscope used in a service center.

Available Downloads

Special insulation helps create larger oven when motor is too big to fit

Special insulation helps create larger oven when motor is too big to fit

Chuck Yung
EASA Technical Support Specialist

 We are cleaning a motor that is too large for our bake oven. In the past, we have placed the motor in front of the oven with the doors open, and draped a tarp over the frame to trap the heat. Is there a better way to dry it out?

Most readers in our industry have used variations on that method to dry the windings of a motor that simply won’t fit in the bake oven. There is a better way. Use Energy Shield®, the insulation home builders install between the exterior frame and siding or brick. It is a stock item in most lumber yards and construction-supply superstores.

Available Downloads

Strive for “lean service” with a focus on the “sort” activity

Strive for “lean service” with a focus on the “sort” activity

5S + 1 series on lean service

By Paul Idziak
Shermco Industries, Inc.

Last fall, the Management Services Committee discussed findings from the most recent Member Needs Assessment Survey. “Lean service” was the number one area where members want EASA to focus its management education resources over the next three years.

For those who may not be familiar with this concept, lean service is an approach to eliminating waste and disorganization with a goal of improving efficiency and productivity. 
To meet this desire for additional resources on lean service, the committee agreed to develop and publish a series of Currents articles on the “5S” program (which you may have heard about), and modifying it to add safety. The traditional “5S” program covers these goals:  sort, straighten, shine, standardize and sustain. We’ve added safety to make it the “5+1 S Series.”

A VIDEO INTRODUCTION TO 5S

Members of the committee will write articles on how each “S” can help you with a path to productivity by becoming more efficient, or lean. I volunteered to write the first article, focusing on the first S: Sort.

Sort activity
The sort activity allows your team to “clean house” to get the essentials for completing future activities effectively and safely.

Start by setting up the criteria to help determine needed and unneeded items in your service center. Factors can include:  frequency of usage, location in facility, whether defective/obsolete, and many other factors. 

After determining the criteria, the team will need to go through the area of interest and “red tag” items considered for purge. As a team, everyone will review red tagged items and make a final judgment as to whether they need to be discarded. 

Before removing the materials from your service center,  investigate if your company has any accounted value for them. The item could be considered an asset and may be in inventory. Also, check with other departments, divisions, or areas of the company that could use the red tagged items. You may even be able to sell the items to help fund your 5+1 S endeavors.

You may find that your team has a strong buy in for the sort step. They may have wanted to get rid of the items for a while and appreciate the clean workspace. 

Next month:  Focus on straighten
Once you complete this step and eliminate the appropriate items,  you’re ready to move on to the next “S” goal:  Straighten. It will be covered in next month’s article.

Strive for “lean service” with a focus on the “standardize” activity

Strive for “lean service” with a focus on the “standardize” activity

5 + 1 S Series

By Tim Hebert
A&W Electric, Inc.

Editor’s Note:  This is the fourth in the “5+1 S Series” of articles written by EASA’s Management Services Committee to provide “lean service” resources to members. The traditional “5S” program covers these goals: sort, straighten, shine, standardize and sustain. We’ve added safety to make it the “5+1 S Series.” 

Standardize refers to identifying specifically what products, inventory, equipment and procedures we use to guarantee a consistently successful outcome for our customers. With proper standardization, we can ensure better product quality and workmanship, more effective training and onboarding programs for new associates, more consistent communications back to our customers and ultimately greater profitability.

But there are challenges, aren’t there? Don’t we feel like our customers are unique? And doesn’t it seem that every piece of their equipment is just a bit different? All those things generally are true. Part of our customer promise is the ability to customize and tailor solutions to meet their needs. However, there is much to be gained by standardizing as much of our processes as possible. And that doesn’t just apply to the repair shop!

Available Downloads

Strive for “lean service” with a focus on the “straighten” activity

Strive for “lean service” with a focus on the “straighten” activity

5S + 1 series on lean service

Ron Collins
Tennessee Associated Electric
Management Services Committee Member

Editor’s Note: This is the second in the “5+1 S Series” of articles written by EASA’s Management Services Committee to provide “lean service” resources to members. The traditional “5S” program covers these goals:  sort, straighten, shine, standardize and sustain. We’ve added safety to make it the “5+1 S Series.”

Last month, Paul Idziak, a fellow member of the Management Services Committee, explained the sort activity and how to use it to determine needed and unneeded items in your service center. This month, I’ll cover the second S:  Straighten.

Available Downloads

The Basics: Motor Repair Burnout Procedures

The Basics: Motor Repair Burnout Procedures

This webinar will cover burnout procedures for AC stators: 

  • Interlaminar insulation materials / properties
  • Core testing before and after
  • Processing equipment, controls and records

The Care & Use of Micrometers

The Care & Use of Micrometers

Frank Conci
Technical Services Committee Member
A.C. Motor Electric, Ltd.

Editor’s note: This is a 2-part article that appeared published in June/July 2021.

The focus of this article is on outside micrometers. The ideas and information are applicable to other mechanical measuring devices such as inside micrometers, calipers, protractors, levels, depth gauges and such.

The importance of precise and accurate measurements is more critical today than ever. Our customers are increasingly demanding of best possible practices and outcomes when having their machinery serviced and repaired. EASA is at the forefront of ensuring that this service level is available through its Accreditation program, technical standards and engineering support. Our customers expect EASA members to use appropriate instruments professionally and dependably to repair and assess their equipment.

Available Downloads

The importance of calibration in the service center

The importance of calibration in the service center

Pat Douglas
Kirby Risk-Mechanical Solutions and Service

Motor repair businesses rely upon the quality of their company’s employees and equipment. Documentation is required more often by customers to satisfy their reliability engineers. Supplying erroneous data, even if it is unintentional, can be very disappointing to a customer.

Instrumentation that is not providing correct information can result in inaccurate diagnosis. This could mean returning a motor that still needs work, or putting unnecessary labor into a customer’s product. Neither of these is desirable and could result in customer dissatisfaction. With more of today’s equipment designed to run at full current and many times into the service factor, the margin for error is drastically reduced.

Available Downloads

The importance of stator core loss testing before and after burn-off process

The importance of stator core loss testing before and after burn-off process

Steve Skenzick
HPS Electrical Apparatus Sales & Service

By this time we should all know that stator core loss testing is a required part of a quality rewind.  A core loss test before and after burn-off is speci­fied in the EASA Recommended Practice for the Repair of Rotating Electrical Ap­paratus (ANSI/EASA AR100-2010) and The Effect of Repair/Rewinding on Motor Efficiency; EASA/AEMT Rewind Study and Good Practice Guide to Maintain Mo­tor Efficiency. I would like to share some core loss testing experiences we have had over the years in our service center.

Available Downloads

The importance, benefits of preheating motor windings prior to impregnation

The importance, benefits of preheating motor windings prior to impregnation

Tom Bishop
EASA Technical Support Specialist 

Did you ever wonder if the preheating instruc­tions from solvent varnish and solventless resin (hereafter we’ll use the term “resin” when it ap­plies to both) manufacturers were really all that important? The short answer is, yes, they are. Here we’ll expand on some of the reasons that preheating is a key step in the winding process. 

One of the first benefits of preheating is that it drives out moisture that may have settled on sur­faces, or been absorbed by insulation material. A little known aspect of pre­heating is that it relieves the mechanical stress cracks, termed “crazing,” on the magnet wire insulation coat­ing that occur during coil winding and insertion. Epoxy B-stage materials can be set by preheating, provided the preheating time and tempera­ture meet the epoxy’s curing requirements. Random wind­ings typically don’t use many B-stage materials; however, many of the lacing products for endturns are thermoset­ting. Form coil windings often have B-stage surge ropes, and some felt packings used for endturn coil bracing are B-stage epoxy loaded. 

Available Downloads

Time-saving features included in updated AC Motor Verification & Redesign program

Time-saving features included in updated AC Motor Verification & Redesign program

By Gene Vogel
EASA Pump & Vibration Specialist

EASA’s AC Motor Verification & Redesign – Version 4 program, released in May, is an easy-to-use update to the prior Version 3, and older Version 2 program. The layout and function of the new program is mimicked from the older Version 2 program, so users can move up to the new program with an easy learning curve. Also there are features in the Version 4 program that will aid in recognizing aspects of the redesign process that can be overlooked. If you have the program running, follow along to learn about these features.

When entering a new design, the Version 4 program provides a field to identify the Customer by name and/or number. A “New” button lets the user enter customer data on the fly, but it is helpful to have the data already entered for your regular customers. The Database -> Customer menu items let you manage your Customer list ahead of time. Then customers can be easily entered by number or selected from the Customer Name dropdown list.

Use keyboard or mouse
When entering the Original Winding Data, some users prefer using the keyboard while others are more comfortable moving through the fields with the mouse. The program supports both methods. The Tab key steps through the data fields (shift-Tab for reverse). Any field with scroll arrows can be set with the Up – Down cursor key, or values can be typed in. Radio button and check boxes can be set with the Space Bar. With the mouse, just operate the scroll arrows or click in any field and type the value. Also, hover the cursor on an icon to see the icon description (see Figure 1).

When the data has been entered, the Calculate button displays a selection grid of possible redesign options. The selection grid is flexible and can be expanded to include additional columns (right click), and columns can be sorted by clicking the column heading. Several options are available to display various numbers of circuits (see Figure 2).  There is a good video tutorial on using the selection grid available from the program Help or though the EASA website. Often, the choice of redesign parameters involves comparing various options. The program allows the user to select and display multiple selections from the selection grid – just hold down the CTRL key and click the desired rows. The various redesign options can then be selected with the Tabs at the bottom of the display. For a columnar comparison of critical parameters, select the Side-by-Side option from the Redesign menu.

Also, there are Round Turns buttons for Integer or Half-Turn settings just above the Calculate button on the Original Motor page. Selecting Half Turns includes those options in the selection grid. An example of half turns is 7.5 turns for a 48-slot, 4-pole machine with 12 groups of 4 which might be wound as 7-7-8-8 with a pitch of 1-11 or 7-8-7-8 with a pitch of 1-12.
Integrated rewind data

In some cases, a “bare core” design is needed when winding data may be unavailable or suspect. The EASA Motor Rewind Data – Version 4, integrated with the redesign program, can help in these cases. By finding a motor in the database with similar parameters, that winding data can be used as the basis for the bare core design. When a suitable motor is found from the database, the MotorDb -> Send to ACR menu item converts the data from that motor into a new redesign case. There is no need to re-enter the data. A video tutorial on this simple process is also available on the EASA website.

It is common to experiment with various winding parameters such as turns, pitch and connections. The best approach is to use the Calculate button to display the selection grid and choose the desired option; the resulting redesign will be opened on a new Rewind option # tab (see Figure 3). The Manual Rewind option provides an input dialog box to adjust these values. Use caution when manually redesigning windings. It is possible to enter “impossible” values such as 4 circuits with 6 poles, which the program would not ordinarily allow. 

Wire size adjustments
One of the most common adjustments is wire size. A winding slot may be too full or too loose, or the chosen wire size may not be available in enough in-hand quantity. The program provides a powerful wire-size calculator to choose combinations of two wire sizes with the calculated percent change. The new wire size values from the calculator are automatically entered into the redesign with new CM/A (A/mm2) values (Figure 4).

There are a number of convenience options available in the redesign program. Core dimensions can be entered as fractions such as 3 11/16, or use simple math to convert values; 3.5 x 25.4 (convert inches to mm). On the Tools menu is an option to Set Available Wire Sizes so that only the wire sizes in your inventory appear. This list works in conjunction with the Wire Sizes Only Available checkbox on the Original Motor page just above the Calculate button. There are Default Value settings for Original Motor data. Select Motor Defaults from the Tools menu and enter whatever data you might commonly use. Common entries are hp – kW and AWG or Metric wire. Save and close the Default Motor and those values will be pre-set for new redesigns. The Reference menu has an array of simple calculators and various commonly used tables, such as Round Magnet Wire data and Three-Phase Full Load Currents. Also on the Reference menu is a PDF version of the AC Motor Redesign manual that has many of the base formulas used to calculate redesigns. The Concentric-to-Lap conversion charts are there also, which some members use for reverse conversions of Lap-to-Concentric. Contact EASA Technical Support for more information on converting to concentric windings.

Once a redesign has been calculated for an Original Motor, the Original Motor data is locked and can’t be edited without deleting the redesigns. This is to prevent a redesign being present that does not match the Original Motor. The Editor -> Allow Edits menu item has options to Delete all Redesigns or Clone Motor. Selecting Clone Motor will create a new Original Motor where the data can be edited. This is helpful for “what if” scenarios, and for multi-winding motors where most of the physical data is the same for each winding. 

In the course of looking up similar motor data in the winding database and redesigning multiple motors, there may be a number of motors open at any time. The tabs at the top of the editor show the motor ID with an Icon for the type of data. When several tabs are present, right clicking any tab will display options for closing unneeded tabs: Close Others, Close Tabs to the Left, Close All.
The program Help has useful information on winding redesign in the Concepts and Tasks sections. The video tutorials available on the EASA website may also be accessed from the program Welcome screen on the Help menu. The tutorial and Help are handy resources when questions arise. Of course EASA Technical Support can also answer questions about features and functions of the program or help with redesign questions.

LEARN MORE ABOUT THIS SOFTWARE

Editor’s Note:  Those who had purchased Version 3 automatically received Version 4 in May 2016. Otherwise, the program may be purchased. 

Available Downloads

Time-Saving Repair Tips

Time-Saving Repair Tips

This webinar shares:

  • The secrets used by other service centers to gain a competitive edge in the repair process.
  • Mechanical, winding and machining tips reduce repair time, help avoid unnecessary rework, and decrease turn-around time.

Target audience: This webinar will be useful to supervisors, machinists, mechanics, winders, and sales personnel who interact with the end user.

Two case history examples point to need for caution with metal spray

Two case history examples point to need for caution with metal spray

Steve Skenzick
HPS Electrical Apparatus Sales & Service

At my service center, we have seen problems with previously repaired shafts that were metal sprayed. In these cases we received motors for overhaul. Upon inspection and measuring the bearing shaft fits, we found something that just didn’t “feel” right. We could tell from the appearance that the shafts had been repaired prior to the current overhaul.

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Una configuración económica para la prueba de núcleos de estatores pequeños

Una configuración económica para la prueba de núcleos de estatores pequeños

Mike Howell
EASA Technical Support Specialist

Las dos razones principales para probar el núcleo de un estator son (1) comprobar que es apto para continuar en servicio y en el evento de un rebobinado, (2) verificar que el proceso de reparación no ha afectado negativamente su estado. Esta prueba se puede efectuar con un probador de núcleo comercial o de forma manual, utilizando una fuente de C.A. adecuada, cables e instrumentos de prueba. Algunas de las razones para realizar la prueba manualmente son:

  • El cliente o el centro de servicio la prefieren / especificaciones 
  • No hay un probador de núcleo comercial disponible 
  • El tamaño del estator es inapropiado para el probador de núcleo comercial disponible 

Además, algunos centros de servicio se abstienen de realizar las pruebas de núcleo en estatores pequeños por diferentes razones. Estas incluyen, dificultades con la configuración de la prueba, cálculos, costos e incluso imagen. El propósito de este artículo es el de explorar una configuración de bajo coste para probar los núcleos de estatores pequeños.

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Using a cost-efficient regenerative dynamometer

Using a cost-efficient regenerative dynamometer

Bill Colton 
Baldor Electric Co. 
Commerce, California 
Technical Services Committee Member 

Today’s cost of energy has become a major consideration in most businesses. This is certainly true of EASA service centers as it is with most industry. We are all trying to find ways to make our facilities more efficient to either become more competitive, or gain greater profits – perhaps both. 

One of the tools that may make an EASA facility more attractive to potential customers is the ability to put a motor under load or even tested to a specified load. 
This is often done with a dyna­mometer. A dynamometer is defined as a device for measuring mechani­cal power, especially one that measures the output or driving torque of a rotating machine. 

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Vibration for Service Centers (12-part webinar series)

Vibration for Service Centers (12-part webinar series)

This 12-part recording (15 hours) covers a wide range of topics on vibration.

Members rely on EASA to provide technical assistance and training in all areas related to machinery repair. In the area of machinery vibration, there are training providers that offer general classes in vibration analysis and balancing, but the content is geared to plant maintenance personnel who would be conducting in-plant predictive maintenance services. Some key areas important to EASA service center technicians is not covered adequately, and much of the content does not apply to vibration testing conducted in the service center. This course is designed to address those shortcomings and provide fundamental training in vibration analysis and balancing that directly applies to technicians working in the service center.

Main goals of the series
This webinar series was designed to:

  • Provide EASA service center technicians with the technical knowledge they need to effectively measure and diagnose vibration on machines being tested in the service center.
  • Provide the foundation understanding necessary to use vibration data as an indicator of machinery condition
  • Provide the fundamental knowledge of dynamic balancing necessary to use common balancing instruments in the service center

LEARN MORE ABOUT THE COMPANION BOOK

Who would benefit from watching this series?
Service center technicians who measure and analyze machinery vibration, and those who must evaluate the vibration data will benefit greatly from the fundamental understanding and knowledge provided by this training series. Service center engineers who may be involved in writing, interpreting and applying vibration and balancing specifications and tolerances will gain a practical understanding of the terms, definitions and parameters encountered in those specifications.

As with any technical subject, fundamental math skills will allow attendees to quickly comprehend concepts and apply techniques. Vibration results from the mechanical and electrical forces at work in machinery, and a fundamental understanding of those forces, and machine components that cause them, will aid in the understanding and application of the subject matter.

Price
Downloadable version - $745 for members, $1,885 for non-members
DVD-ROM version (for viewing on a computer) - $795 for members, $1,985 for non-members

Part 1

Introduction and Overview

  • Vibration – a key indicator of machine condition
  • A complex measurement of amplitude, frequency & phase
  • Historical perspective of machinery vibration measurement
  • How it is applied to new and repaired motor
  • Broader applications of vibration measurement
Part 2

Amplitude, Frequency and Phase

  • Vibration parameter units (mil, in/sec, etc.)
  • Basics of the spectrum
  • Basic vectors
Part 3

Vibration Tolerances

  • NEMA vibration specifications for new motors
  • IEC / ISO vibration specifications

Part 4

Basic Vibration Analysis (Part 1)

  • Recording and reading vibration spectra
Part 5

Basic Vibration Analysis (Part 2)

  • Using the time-waveform display with the spectrum
  • The time-waveform and spectrum relationship
Part 6

Dynamic Balancing Basics

  • Single-plane balancing
  • Understanding phase angle
  • Two-plane balancing
  • Balance tolerances
Part 7

Resonance

  • Natural frequencies and structural resonance
  • Bode plots
  • Flexible rotor and critical speeds
Part 8

Time and Speed Transient Analysis

  • Waterfall spectra display
  • Identifying resonance
  • Data acquisition techniques
Part 9

Rolling Element Bearing Vibration

  • Characteristics of vibration from bearing faults
  • Calculating bearing fault frequencies
  • Assessing bearing condition
Part 10

Demodulation and High Frequency Band Measurements

  • Overview of various high frequency direction schemes
  • Demodulation basics
Part 11

Field Analysis Techniques

  • Setting up PdM programs
  • Tips on field vibration troubleshooting
Part 12

Field Balancing—Problems and Solutions

  • Tips on field balancing

 

Vibration Instrumentation Overview

Vibration Instrumentation Overview

Gene Vogel
EASA Pump & Vibration Specialist

The ability to measure machinery vibration is essential to machinery repair. But vibration is a complex phenomenon, with multiple parameters; specifically, amplitude, frequency and phase. So unlike temperature, pressure or other single parameter indicators, to use vibration as an effective machine condition indicator, technicians need more than simple meter and 5 minutes of instruction. The most common vibration related task for EASA service centers is acceptance testing for repaired machines. Even this basic task requires:

  • Knowledge of vibration fundamentals
  • Adequate vibration instrumentation
  • Documented acceptance criteria
  • Proper mounting methods
  • An awareness of advance analysis techniques

This paper addresses the concerns related to insuring the service center has adequate vibration instrumentation. While needs vary among service centers, the basic instrument required is a portable vibration analyzer. In order to qualify as a vibration analyzer, the most basic instrument functions are the ability to measure vibration amplitude and frequency, and common tools for analyzing a vibration spectrum. There are a number of instruments that meet these basic requirements, and most offer additional useful capabilities. Choosing an instrument that meets a specific service center’s needs should involve all of the stakeholders, which includes owners, managers, engineers and technicians. For smaller service centers, it may be one person who wears all those hats, and the decision process is simplified. For larger service centers, input from a dozen people may be needed, and there will be trade-offs on costs vs. benefits. In either case, and those in between, it’s important that considerations include:

  • Features and capabilities
  • Cost
  • Convenience
  • Durability
  • Support
  • Training

This paper focuses on features and capabilities. Not to diminish the importance of the other components, but those are best left to discussion between the service center and the various instrument vendors.

This paper covers:

  • Heritage instruments
  • Spectrum analyzers
  • Balancing instruments
  • Online monitors
  • Portable vibration level meters
  • Proximity probes and instruments
  • Accelerometer transducers

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Volatile organic compounds (VOCs): How to reduce or eliminate them in your service center

Volatile organic compounds (VOCs): How to reduce or eliminate them in your service center

Tom Bishop, P.E. 
EASA Technical Support Specialist 

Volatile organic compounds (VOCs) are found in our homes, in stores, in our offices and service centers. VOCs allow paints to dry quickly and cleaners to quickly loosen and remove dirt and debris. But VOCs do have a downside in that they bring serious health and environmental risks into our workplaces. Many service centers feel that these negatives far outweigh the benefits. 

In simple terms, any organic compound that evaporates into the air is, by default, a VOC unless it is listed by the applicable environmental compliance agency as an “exempt compound.” We want to minimize the use of VOCs because they contribute to air pollution.

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