Comparison of ANS/NEMA and IEC requirements for low voltage motor control center

If engineering design we are able to apply either IEC or NEMA style products, we need to know the differences between NEMA and IEC designs. Both style designs have features and benefits, designer criteria will be guided in obtain the optimum design for particular cases. The proper motor and motor control center selection required to know many criteria for select them. Effective selections of modern motor control centers (MCC) require a strong working knowledge of rotating machine basics as well as an in-depth awareness of the latest technical developments. When a few motor starters are needed, they are typically installed within a standardized vertical enclosure with all the required relays, instruments, and controls that required of an effective deep knowledge of the standards for the correct installation. This paper present a revision and summarize reflexive of the "state of the art" for proper MCC selection to show the works presented in this area, in way of taking out a practical guide for the correct design of MCC and developing a methodology as tool for the design, establishing for this a comparison of the American standards (ANSI/NEMA) and the international standards (IEC) for particular cases.