A Gameplan for Building Automation Systems and Energy Efficiencytest

By Scott Lance

April 2015

Typically, maintenance and engineering departments use a building automation system (BAS) front end for alarming, trending and viewing. In reality, a BAS front end is more than just a graphical interface that gives operators of buildings and systems a place to visually monitor mechanicals.

By optimizing the front end of a BAS, managers can give their staffs a powerful tool to uncover minor issues before they become major issues, as well as to assist in the maintenance of systems.

New-Generation BAS

No two BAS front ends are alike, but they all have the same base functionality. About 10-15 years ago, BAS front ends were just a means to view the operation of a building's control systems. Now, operators can add advanced links to graphics. These links can access other systems related to the one being viewed, or to information about the systems. The front end can be a one-stop shop for most information about individual systems.

Graphics typically are built by individual systems, including air-handling units (AHU), chilled water, hot water, and variable-air-volume (VAV) units. But graphics rarely give a complete overview of the entire system. Consider an AHU serving 50 VAVs. Each room has an individual graphic, and the AHU has its own separate graphic.

For instance, an AHU modulates a fan to maintain static pressure. If all systems are within temperature setpoint and there are no complaints from occupants, operators can assume all systems are operating correctly. This might not be true, though. A simple graphic showing all damper positions or valve positions for all VAVs served by an individual AHU can report a great deal of information about a system's current status very quickly.

Unless a system is operating on a day where the outside air temperature is above or below a design day, or the controls logic is operating a morning warm-up scenario, there should be no reason for VAV valves or dampers to be 100 percent open. A simple graphic with this information can help operators quickly locate the issue while it is still minor.