Open, Interoperable Systems For Energy Control
Michael R. Tennefoss · Strategic Planning for Energy and the Environment · 1998
The advent of solid state technology offered a means of using logic circuits to replace wire and relays. Electrical panels gave way to programmable logic controllers (PLC), which were programmed not with a screw driver but a data terminal. These PLC, first developed for the industrial process control industry, gradually migrated to the environmental control industry in the form of Direct Digital Control (DDC). If one wanted to interconnect DDC from different manufacturers, the incompatibilities between manufacturers led engineers to focus on linking separate systems with relays, custom gateways, and RS-232 ports. The problem is that these interfaces didn`t provide a detailed, seamless view into the different systems. The world of energy control systems has come a long way technologically since the advent of solid state controls. The availability of LonWorks control network technology, and of products like the LonPoint System that use this technology, opens the door to a new generation of energy control systems. Besides offering capabilities not previously available from control systems, open, interoperable systems offer higher reliability, greater vendor choices, and lower life-cycle costs than closed, controlled-based systems. The benefits to be reaped from these systems, both in terms of energy savings and lower system costs,more » are limited only by one`s imagination and vision.« less