Starting a large motor, even with modern soft-start equipment, is frequently problematic. With ever increasing focus on power quality, an electric utility can experience voltage sag problems when an industrial customer installs a large motor (400 - 2500 HP). Other customers can be adversely affected as well as the company with the mo-tor(s). Of course, the utility is generally blamed by both. Solving these problems is not trivial. Capacitor assistance can be a viable and relatively inexpensive solution but it must be done correctly. This paper discusses the benefits (both for customers and for the utility), techniques, problems, relative costs and savings, alternatives, and analysis of capacitor assisted motor starting. Examples of actual installations and case studies will be shown. Index Terms - Motor start, capacitor assistance, soft start, voltage sag, voltage fluctuation, voltage surge, power quality, zero voltage closing.
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