HVAC Control in the New Millennium.pdf - HVAC.Amickracing

HVAC Control in the New Millenniumcontrol in the same system.SERCOS can lessen wiring costs. An analog-motor drive can have16 wires. Simplified wiring means less wiring errors. Networking drivesand controls through the SERCOS interface is a straightforward matter.With the ability to manipulate every variable in a drive system, SERCOSdigital drives have brought drive setup and optimization into thegraphical environment of Windows.Although the standard allows a maximum of 254 programmabledriveconnections in each fiber-optic ring, the actual drive limit can beless depending on the communications cycle time and how much datamust be passed for the application. The cycle time is also a factor if thesesystems are used in building applications.SERCOS was designed for synchronous applications. The actualvalues are detected and commanded values acted on by all drives simultaneously.The drives work synchronously, so beat frequencies or harmonicsare eliminated.Suppliers of SERCOS motion-control cards and equipment includeIndramat, Motion Engineering, and Pacific Scientific. New SERCOS systemsmay be capable of 10-Mbps rates. Digital technology means motion-controlsystems can be more precise and easier to use and SERCOSrepresents a future away from proprietary systems.ReferencesAnderson, Edwin P., Air Conditioning: Home and Commercial, MacmillionPublishing Company: New York, New York, 1985.Brumbaugh, James E., Heating, Ventilating and Air Conditioning Library,Vol. 1, Theodore Audel and Company: Indianapolis, Indiana, 1986.©2001 by The Fairmont Press, Inc. All rights reserved.