Overload for ASD applications - how much is required?

The paper lists various factors that define the continuous rating of an adjustable speed drive. Operating scenarios are discussed that lead to requirements for temporary overload capability. Specification of adjustable speed drive overloads is addressed along with methods that can be employed to avoid overloads. Common industrial machines are categorized according to their overload requirements, and application exception examples are provided. General requirements for adjustable speed drive overload capability, as defined in NEMA and IEC standards, are reviewed and compared, and recommendations are given for additional user specifications that are appropriate for AC motor drive applications.