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

HVAC Control in the New Millenniumronmental-impact program. The Seriplex system links 200 panel-boardsto a central PC which controls the entire lighting system. Replacing thepoint-to-point wiring, Seriplex made it possible to retrofit this 1952-eraplant with PC lighting control with minimal wiring and installation time.Seriplex was developed by Automated Process Control (APC), in1987. Square D bought APC in 1995 and created the nonprofit SeriplexTechnology Organization. This device-level control network has beenused in North America, Asia, and Australia with more than 3 million I/O points installed at more than 3,000 locations. Besides Square D,Seriplex manufacturers include Turck, Pepperl+Fuch, ABB Flexible Automation,Banner Engineering, Delta Automation, GE Fanuc Automation,MAC Valves, and Wonderware.Seriplex technology was designed mainly for sensors, actuators,and simple on/off devices. It is deterministic, with speeds in the lowmilliseconds.A single network can accommodate several thousand I/O devicesand extend more than 5,000 feet. The network allows for the control andmonitoring of analog and digital devices.Seriplex chips are embedded in sensor and actuator devices. Thisprovides the connection to the bus. The bus is a serial, multiplexed,intelligent, distributed I/O system with master/slave and peer-to-peerI/O control and logic. Seriplex technology can replace large bundles ofpoint-to-point wiring with a single thin cable.Seriplex can reduce downtime and improve safety. It allows operatorsin a central control station to quickly locate the source of breakdowns.Seriplex and EthernetSeriplex may be able to be paired with Ethernet. This would replacemultiple levels of proprietary and often incompatible networks with asystem of open technology. Several trends could make this possible.One is the emergence of Ethernet and TCP/IP as de facto standards.Most intelligent devices are compatible with Ethernet. TCP/IP isthe technology that makes it possible for computers to view data overthe Internet.As Ethernet moves from a shared to a switched design, it canparticipate in time-critical functions for automation and control. The©2001 by The Fairmont Press, Inc. All rights reserved.