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 [FIGURE 1-2 OMITTED]When irgasaircompressor the magnetic bearings are energized, irgasaircompressor the motor and impellers, which are keyed directly to the magnetic shaft, levitate. Permanent-magnetic bearings do the primary work, while digitally controlled electromagnets provide the fine positioning. Four positioning signals per bearing hold the levitated assembly to a tolerance of 0.00002 in. As the levitated assembly moves from the center point, the electromagnets'' intensity irgasaircompressor is adjusted to correct the position. These adjustments occur 6 million times a minute. The software has been designed to automatically compensate for any out-of-balance condition in the levitated assembly.SHUTDOWNS AND POWER FAILURESWhen the compressor is not running, irgasaircompressor the shaft assembly rests on graphite-lined, radially located touchdown bearings. The magnetic bearings normally position the rotor in the proper location, preventing contact between the rotor and other metallic surfaces. If the magnetic bearings fail, the touchdown bearings (also known as backup bearings) are used to prevent a compressor failure. Efficiency is further enhanced with the use of magnetic bearings, which avoid fire friction of rubbing parts associated with traditional oiled bearings. Conventional bearings can use as much as 10,000 w, while magnetic bearings require only 180 w. That amounts to 500 times less friction loss. Current development projects are expanding the range and duty of the compressor wheels and promise to offer even greater efficiency for water-cooled and air-cooled duties and different capacities.CONTROLSThe new compressor effectively is a computer. It provides diagnostic and performance information through Modbus to the refrigeration system, which then communicates to the building automation system through Modbus, LonWorks, or irgasaircompressor BACnet.CHILLER APPLICATIONThe compressor manufacturer and a major chiller manufacturer teamed up to develop a line of ARI-certified water-cooled chillers, which were expected to be introduced in January 2004. The combination of flooded-evaporator technology and an oil-free system has allowed very close approaches and, subsequently, enhanced performance. The integrated VFD allows excellent part-load performance as power consumption drops off, depending on the head relief, near the cube root of the shaft speed. Buy a gas air compressor with us and save a TON of cash. Our selection of cheap gas air compressors is second to none.
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