The widespread use of electronics in everything from equipment in the home to the control of huge and costly industrial processes has raised the awareness of power quality issues a.nd concerns over the last few years. The definition of'power quality or more specifically, a power quality disturbance, is generally accepted as: any change in the power (voltage, current, or frequency) thi3t interferes with normal operation of electrical equipment. It is the susceptibility of the end-use equipment that defines the necessary level of Dower quality.The intent of this paper is to present information on power quality issues as they affect end-use equipment. The goal of industrial customers is, of course, to stay competitive in the production of their particular product or service. One effective way of accomplishing this is to reduce downtime and thus production loss by limiting the effects of power disturbances. The goal of electric utilities is to maintain a healthy and effective relationship with customers while also promoting the use of electrical energy. It is essential that industrial customers and the utility work together to provide solutions to power quality problems. This paper will define power disturbances in industryaccepted terms, examine the sources and effects of these disturbances (for both the utility and the industry), and explore economical s'olutions based on the compatibility of the equipment and the electrical environment.

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When chilled water refrigeration loops and air handling units are operated manually, the resulting inefficiencies cause higher electrical power requirements than necessary.Installation of an automatic air conditioning control system maximizes chiller efficiency, minimizes the number of chilled water pumps operating while maintaining adequate capacity, and controls the air volume by varying fan speed to move only the air required to maintain desired room conditions. Project payback may be less than three years, depending on energy cost6. with the space conditions actually improving by providing a more even control of temperature and humidity. Details provided include selection of control equipment, calculation of savings, motor load reading techniques, and adjustable speed drive fundamentals involving selection of equipment,

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