ABSTRACT
Systems Engineering Activities________ Perhaps the most important engineering activity during the design/development phase of the project, with the greatest impact on the performance of the envi ronmental control system, is the DDC systems engineering and generating of application software. This phase is the least understood (and appreciated) out side of the controls systems engineering community. However, DDC systems engineering and related application software (such as controls logic, automa tion programs, report generation, Person Machine Interface, communications, and other relevant programs) determine:
a. The future operation of the environmental controls system, and conse quently the quality of the building environment
b. The level (degree) of automation for the facility c. Energy savings for the controlled building(s) d. Reduction of operating and maintenance costs due to
• Designed hardware and application software • On-line detection of related environmental control systems and build
ing problems • On-line analysis of problems, and assignment of appropriate trades • On-line transfer of information to a job scheduling or maintenance
management system • Generation of energy, problem (alarm), and management reports • Reduced number of nuisance calls • Generation of trends and history data for situation analysis
e. Reporting of fire, safety, and security alarms from the connected build ings
f. The volume (and value) of information exchange with other facilities automation systems
Many traditional project teams are still hardware oriented, and have limited un derstanding and appreciation for the discipline so important for the operation of modern facilities. This may have its roots in years of specifying single loop pneumatic controllers for building HVAC controls. Some engineers on the de sign team perceive DDC systems as if they were “solid state” single loop pneu matic controllers. This perception prevents full utilization of the system’s avail able features in facilities automation. The limited vision, along with the desire to select the lowest cost DDC system, have adverse effects on the design of the environmental controls system, its future performance, and on the degree of au tomation of the facility. Limited understanding most likely leads to underuti lization, whereas full understanding of the DDC system’s capabilities, and de velopment of its applications software, provides true “building automation.”
