Spectrum analysis is the primary tool for analyzing vibration problems. Yet, a lot of useful information can be acquired by tracking the vibration characteristics as power is disconnected from the machine.

Simple diagnostic tests—such as bump tests and speed‑variation checks—can be used to identify resonance as the cause of high vibration in rotating machinery. By recognizing when vibration frequencies align with natural frequencies, technicians can diagnose resonance issues early and avoid unnecessary corrective actions.

Este artículo explica cómo pruebas diagnósticas simples —como las pruebas de impacto (bump tests) y las verificaciones mediante variación de velocidad— pueden utilizarse para identificar la resonancia como causa de alta vibración en maquinaria rotativa. Al reconocer cuándo las frecuencias de vibración coinciden con las frecuencias naturales, los técnicos pueden diagnosticar problemas de resonancia tempranamente y evitar acciones correctivas innecesarias.

Like many EASA member service centers, Good Fruit Electric, LLC has learned that growth and sustainability depend on one thing: finding good people and helping them become productive quickly. Over the years, we’ve refined how we recruit and train new team members, but the process became far more effective when EASA introduced its learning management system.

Emotional intelligence is simply the ability to recognize, understand and manage your own emotions— and to recognize and respond to the emotions of others. When leaders grasp this side of their teams, performance improves—but more importantly, people grow. They become problem-solvers instead of task-doers. They become the next generation of leaders.

This webinar recording shares practical solutions for mechanics and winders to overcome common challenges and streamline their daily work.

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.

La norma ANSI/EASA AR100 es una guía indispensable para la reparación de máquinas eléctricas rotativas. Su objetivo es establecer las prácticas recomendadas en cada etapa de los procesos de rebobinado y reconstrucción de aparatos eléctricos rotativos.

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.