Building Automation Systems

Modern buildings have progressed from the days when a building engineer would arrive early in the morning to start HVAC systems and then shut down these same systems at the end of the workday. With modern Building Automation Systems (BAS), these HVAC systems now automatically start and stop equipment based on a schedule.

The schedules are created by compiling inputs from many users (typically at the beginning of each semester) and then a facilities staff member enters the appropriate schedule in the BAS.

The reality is that while one zone may be in use 16-hours per day, the adjacent zone might only have 2-3 hours of occupancy per day.

Within a BAS, schedules can be programmed at many levels from the individual zone or room, to the floor level, the building level, and even the campus level. At the lowest level (the individual zone), there are thousands of schedules and managing each zone at this level requires substantial manpower. Given this reality, the zone level schedules are actually inherited from a higher level, predominantly the building level. This means every zone in a building typically works off of the same schedule.

This would be a great approach if every zone in the building operated the same hours each day. The reality is that while one zone may be in use 16-hours per day, the adjacent zone might only have 2-3 hours of occupancy per day.

Automated Systems

Data Systems Analysts (DSA) can develop and deploy a system to improve scheduling and capitalize on this opportunity. By automatically passing the specific schedules for a zone to the HVAC system, HVAC can be activated at the zone level, on an as-needed basis. This is accomplished using the PI SystemTM.

The automated system accounts for warm up and cool down time so each zone is appropriately conditioned for the full period of occupancy. As the system becomes more intelligent, the bookends will be optimized by accounting for the thermal inertia and recovery time for each space.