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

Computer Networks and Security 305Chapter 8Open Systems andDevice NetworksIn today’s energy management climate, increasing costs and theneed for improved efficiency of building systems forces ownersto take a hard look at their building automation systems.Many industries must comply with new environmental and safetyrequirements. In such a business environment, less of the required dataare control specific. More information of other types is needed to maintain,diagnose and modify the control system.Standard digital networks have additional benefits. Reduced wiringlowers installation and maintenance costs. Open systems allowsusers to select the right equipment for the job, regardless of the systemmanufacturer. The networks also have intelligent instrumentation, inwhich better performing devices provide functions such as advanceddiagnostics.The networks offer distributed control with intelligent devices thatprovide the flexibility to apply control centrally or at local processingpoints for improved performance and reliability. Those available rangefrom low-level systems that gather data from simple discrete sensors tomore sophisticated networks in which intelligent field devices implementdistributed control.Open and Standard ProtocolsThere is some difference between an open protocol and a standardprotocol. Open means that anyone is free to use the protocol. Standardmeans the document that describes the protocol has been through aprocess and been reviewed by a variety of interests which may includeusers, vendors and supporting agencies.©2001 by The Fairmont Press, Inc. All rights reserved.