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

HVAC Control in the New MillenniumIt uses desktop computer technology to associate control system iconswith a programming scheme to form objects. These objects haveprewritten, generic code that provide the sequence of control operations.This allows standardized coding and forms an object library. It clarifiesthe sequence of operations and displays how to achieve it. This providesa framework for standard programming across many vendors as well asbetter comprehension of the program from various levels. Graphic realtimediagnostics are possible in a graphic environment, using objectflowcharts as a diagnostic real-time graphic.The newer software is engineered for exception entry and requiresless work to maintain operations. Audio and video enhancements in thefuture will make it easy to catalog equipment and describe maintenanceprocedures. The trend in maintenance management will be towardsproducts that are easily modified.Open Protocol IssuesNatural forces will define the future of open protocols. The termopen protocol refers to a standard communication format based on theexchange of specific modular decisions, which are also called objects,between control systems manufactured by unrelated companies.Ideally, this could allow open competitive bidding even on largeprojects that may occur over several years. The concept of open systemsoriginated in the mid-1980s, due to the financial and operational impactsof evolving building automation systems (BAS). Advances in microprocessortechnology and the new applications of terminal unit controllersfor small HVAC systems, chillers, unit ventilators, and VAV systems,defined rapid advancements and new products that rarely communicatedwith previous controllers.GatewaysThe need to support existing systems lead to expensive approachesto close the communication gaps with communication gateway devices.These are communication translators and multi-vendor protocol hostsoftware systems. They provide central host software functions whilecommunicating with controller networks using dedicated communica-©2001 by The Fairmont Press, Inc. All rights reserved.