When an AC motor is initially energized at rated voltage (and frequency), the current drawn is many times rated current until the motor attains full operating speed. Consequences of starting current include short time overheating of stator windings and rotors, undesirable operation of overload protective devices and a sag in the supply voltage.

Cuando se energiza inicialmente un motor de CA a su voltaje nominal (y frecuencia), el motor toma varias veces la corriente nominal hasta que alcanza toda la velocidad de operación. Las consecuencias de la corriente de arranque incluyen: Breve sobrecalentamiento de los bobinados del estator y del rotor, disparos no deseados de los dispositivos de protección y caídas de voltaje en el suministro eléctrico.

There are a lot of factors to take into consider when interpreting the bar-bar test or surge test. This articles reviews those factors.

Hay muchos factores a tener en cuenta al interpretar la prueba de barra-barra o la prueba de sobretensión. Este artículo revisa esos factores.

The US Department of Energy (DOE) has issued rulemaking on test procedures for small electric motors for more than a decade. The present “final rule,” effective February 3, 2021, is the culmination of those efforts.

This webinar covers the results and the technical details of the recently completed follow-up to the 2003 EASA/AEMT Rewind Study.

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.

In 2003, EASA and AEMT (Association of Electrical and Mechanical Trades in the UK) issued a report that proved rewinding motors in accordance with prescribed good practices would maintain efficiency and reliability. But in recent years, claims abounded that premium efficient motors could not be rewound without degrading efficiency. This recording discusses the latest EASA/AEMT research that included independent, third-party testing.

This webinar recording looks at several aspects of winding design to prevent increased temperature rise and decreased efficiency.

Is the motor drawing high no-load amps and winding data are correct? Are you experiencing unusual heating of the stator under load? Those common questions can be answered by checking the stator core condition.