Variable frequency drives are a system for controlling the revolutions per minute in an electric motor. It is a type of adjustable speed drive that can be added to any in industrial, OEM, and HVAC motor driven system. They can be used in conjunction with control pumps, fans, Condenser fans, air handler motors, HVAC fans, and cooling towers.
Traditional heating and cooling systems often run at a higher speed then necessary which wastes considerable energy. Also frequent starting and stopping of motors and quick accelerations can lead to short life spans for equipment. VFD’s allows for gradual acceleration and less wear and tear on equipment. They work by alternating applied voltage by converting the fixed-frequency supply voltage to a continuously variable frequency, thereby allowing for adjustable motor speed. With variable frequency drives, motors can run at pre-determined speeds to optimize system requirements and energy efficiency performance on fans and pumps. Annual chiller energy consumption and carbon dioxide emissions can be reduced by as much as 30% since lower compressor speed causes reduced wear. Systems can also be programmed to run at times that take advantage of off-peak energy rates.
VFD’s are programmable, quiet, have high motor efficiency and smooth performance. They come in a range of Horsepower and supply voltages. VFD’s are most effective when they are the ideal size and voltage for a specific motor. Digital displays and keypads make programming a breeze and the display can also monitor and show diagnostic information. Many models offer a remote display when the VFD is mounted interior of the equipment, as with many Rooftop air conditioners.
VFD can have an ROI of one year in the right application. They also are available for rebates and incentives the Connecticut and the local utilities. Incentives include the Energy Efficiency Fund Small Business Energy Advantage Program through the UI for a 0% interest rate for amounts between $500 – 100,000; as well as Energy Efficiency Fund Commercial and Industrial Energy Efficiency Program for varying Incentives that incorporate two electric end-uses with at least 15% of project energy savings.
Controlled Air, Inc. uses Eaton Variable Frequency Drives under the Johnson Controls label and we can provide a 3-year warranty when one of our trained techs start and test them. Often ABB VFD’s are used because they are better known. We feel that the Eaton VFD’s offer a competitive solution in cost, quality, easy of operation, support, and warranty.