Motors and Variable Speed Drives

A great deal is spoken and written about energy efficiency. Occasionally something even gets done. There is now a second classification system for the efficiency of electric motors, designed to exploit their full potential. To that end, the new standard also lays down prescriptions for the use of frequency inverters such as Variable Speed Drives (VSDs). This raises questions such as what exactly does such an inverter do and how does it achieve what it achieves? Which motors save energy and which do not? And which must achieve additional energy savings according to the new standards? This Application Note sheds a light on the answers to all of these questions.

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  • Opting for high efficient motor system pays will often pay itself back in less than a year.
  • Technical difficulties to do so are modest.
  • The main obstacle are split budgets: in medium to large companies, the electricity bill is often paid by a different cost centre than that which pays the new motor.