ANSI/EASA AR100 is a must-have guide to the repair of rotating electrical machines. Its purpose is to establish recommended practices in each step of the rotating electrical apparatus rewinding and rebuilding processes.

Many service centers are unable to perform full-load testing of large DC machines. The good news is that there are specific tests that can be performed on a DC motor to verify the integrity of windings, the correct relative polarity of armature to interpoles, and proper running performance. This article explains specific tests that can help ensure a motor operates properly when the motor is installed. 

Does your electric motor service center have prescribed standard operating procedures? When we hire a new team member, we load them up with policy, safety and procedural manuals, often including resources like ANSI/ EASA Standard AR100-2020. Yet, many service center owners and managers have a disconnect when it comes to formal skill development programs.

The purpose of this article is to explain the basis and application of rules used to “estimate” fan performance for a fan installed in a duct system moving air when the speed of the fan is changed.

Muchos centros de servicio no pueden realizar pruebas a plena carga en máquinas de corriente continua grandes, sin embargo, la buena noticia es que existen pruebas específicas que permiten verificar la integridad de los devanados, la polaridad relativa correcta entre la armadura y los interpolos, y el adecuado funcionamiento del motor. Este artículo explica pruebas específicas que pueden ayudar a garantizar que el motor funcione correctamente una vez instalado.

El propósito de este artículo es explicar los fundamentos y la aplicación de las reglas utilizadas para estimar el rendimiento de un ventilador instalado en un sistema de conductos que mueve aire al variar su velocidad. Con un conocimiento básico de estas reglas, es posible calcular rápidamente el rendimiento de un ventilador para diversas condiciones de velocidad.

This presentation covers the important details for a properly converting a 3 phase winding from concentric to lap.

Identificar los cables sin marcar en los motores trifásicos es una tarea habitual para los técnicos de los centros de servicio. Este artículo presenta un método para asignar números a los cables de una máquina de 12 cables con los terminales sin marcar.

En el mundo de la maquinaria rotativa, términos como balanceo, holgura y alineación son habituales para ingenieros y técnicos. Pero hay un concepto que a menudo se esconde a simple vista, crucial para el rendimiento, la longevidad y la seguridad: la alineación del centro magnético.

No importa donde opere en el mundo, la respuesta más común a los desafíos parece ser redactar una nueva norma, directriz o marco regulatorio. El resultado suele ser un sistema de calidad que se convierte en una montaña de documentos, procedimientos y procesos, cada uno concebido para garantizar la calidad, pero que en conjunto amenaza con agobiar tanto a los tall-eres como a los ingenieros.

Identifying unmarked leads in three-phase motors is a common task for service center technicians. This article provides one way to assign lead numbers for a 12-lead machine with unmarked leads.

Have you ever been out at a restaurant or sports bar to meet up with some friends and colleagues to have an adult beverage or two when suddenly someone leans on the table ever so slightly and liquid spills everywhere? What just happened? The small space between the table leg and the floor has just created a big consequence. While it’s not too difficult to solve if you have some napkins and a few coasters, it does, however, illustrate the results of a soft foot and how a very small space can lead to a much larger consequence.

No matter where you operate in the world, the most common response to challenges seems to be drafting a new standard, guideline or regulatory framework. The outcome is often a quality system that grows into mountains of documents, procedures and processes—each one intended to ensure quality, but collectively threatening to overwhelm both workshops and engineers.

In the world of rotating machinery, terms like balance, clearance and alignment are second nature to engineers and technicians. But one concept often hides in plain sight—critical to performance, longevity and safety—magnetic center alignment.

This presentation focuses on the proper clearances, materials and installation process for centrifugal pump wear rings.

Equipping a pump test facility for variable speed operation can provide greater flexibility and expand opportunities to evaluate pump performance.

Emplear velocidad variable durante las pruebas puede brindar mayor flexibilidad y ampliar las oportunidades para evaluar el rendimiento de las bombas.

While highly effective for control, pulse width modulation introduces high-frequency transients that can compromise motor reliability if left unchecked.

A tilted or improperly sized oil standpipe can allow oil to migrate upward along the pipe’s wall when the motor is in operation, leading to leakage, loss of lubrication and potential bearing damage. This issue can be overlooked during assembly or inspection, but a few simple checks can prevent costly problems. 

A thoughtful succession plan—such as hiring a new manager one year before the retirement of the veteran employee—can turn the process of leadership transition into a positive, future-focused evolution.

Si bien es muy eficaz para el control, la PWM introduce transitorios de alta frecuencia que, si no se controlan, pueden comprometer la confiabilidad del motor.

This presentation provides a practical overview of applying both NFPA 70E (electrical safety) and 70B (electrical maintenance) standards to field and shop operations.

Often when we are dealing with three-phase squirrel cage motors we ask ourselves “Is there a standard or a rule of thumb for this motor characteristic?” The 10 characteristics that follow apply to conditions associated with motor starting as well as steady state operation. Examples are provided for each of the characteristics.

We all need friends, right? Isn’t the world a better place when you have someone to share it with? Electric motor shop leaders are no different. Peer groups have long been known as a means by which to advance collective goals and performance. EASA’s Roving Chief Executive (RCE) groups are exactly that - tailored to the executive, owner or general manager of electromechanical repair facilities.

A menudo, cuando trabajamos con motores trifásicos jaula de ardilla, nos preguntamos: "¿Existe una norma o regla general para esta característica del motor?". Las siguientes 10 características aplican tanto al arranque del motor como al funcionamiento en estado estacionario.

This presentation covers induction motor basics for squirrel-cage and wound rotor motors.

There is now a much-needed DC repair standard, created through the participation of EASA members and industry motor users.

Existe ahora una norma para las reparaciones de CC muy necesaria, creada gracias a la participación de miembros de EASA y usuarios de motores de la industria.

When repairing electrical apparatus of any type, a common task is to ensure that machined fits are within acceptable limits of Geometric Dimensioning and Tolerancing (GD&T). The complexity of the task, of course, adds time, and time is never in surplus at a motor service center. Skipping these GD&T checks to save time can lead to mistakes and failures, with costs ranging from a few days of additional work to complete motor replacement and possibly lost production time for both the customer and the service center.

Al reparar aparatos eléctricos de cualquier tipo, una tarea común consiste en asegurar que los ajustes mecanizados se encuentren dentro de los límites aceptables del Dimensionamiento y Tolerancia Geométrica (GD&T).  La complejidad de la tarea, por supuesto, implica tiempo adicional, y el tiempo nunca sobra en un taller mecánico. Omitir estas comprobaciones GD&T para ahorrar tiempo puede provocar errores y fallos, con costos que van desde unos pocos días adicionales de trabajo hasta completar el reemplazo del motor y la posible pérdida de tiempo de producción tanto para el cliente como para el taller.