This article provides practical rules of thumb for evaluating the performance and health of three-phase squirrel-cage induction motors in industrial environments. Rather than requiring detailed engineering calculations, these guidelines help maintenance professionals quickly identify operating conditions that may lead to reduced reliability, overheating, nuisance trips, or premature motor failures.

Performance curves are among the most crucial and frequently requested documents from fan manufacturers, second only to dimensional prints. While many request these documents, not everyone fully understands their significance or maximizes their potential.

Las curvas de rendimiento se encuentran entre los documentos más importantes y solicitados a los fabricantes de ventiladores, superadas únicamente por los planos dimensionales. Si bien muchos solicitan esta documentación, no todos comprenden plenamente su importancia ni aprovechan al máximo su potencial.

Few things are less exciting in the motor world than a large synchronous motor that refuses to start—and all too often, the root cause is excitation. This article provides an overview of what synchronous motor excitation is, how it works, and the common issues you are likely to encounter.

Pocas cosas resultan menos estimulantes en el mundo de los motores que un gran motor sincrónico que se niega a arrancar; y, con demasiada frecuencia, la causa raíz reside en la excitación. Este artículo ofrece un panorama general de qué es la excitación de un motor síncrono, cómo funciona y los problemas habituales que es probable que encuentre. 

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This article explains the key considerations when replacing a failed motor with one built to a different standard. As IEC motors become more common in North America, maintenance professionals increasingly face situations where an IEC motor may need to be replaced with a NEMA motor, or vice versa. While this is often possible, the two standards contain important differences that must be evaluated carefully to avoid performance, reliability, and installation problems.

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.

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.