Abstract: An environmental control system includes a plurality of electronically controlled zone controllers mounted on local VAV boxes for regulating the lighting, temperature and ventilation in a plurality of small zone areas. Each zone controller includes a timer which may be adjusted dynamically to change environmental requirements for zone occupants. A remote master computer is coupled to each local controller to provide three modes of lighting and HVAC equipment control. The inventive method of using the system includes controlling selectively individual ones of the zone controllers to provide three modes of operation an OCCUPIED mode, a STANDBY mode, and an UNOCCUPIED mode where the time period for each mode is adjustable either locally from the zone or remotely from a remote console.

Abstract: A variable air volume ventilating system includes a fan volume modulator, for controlling a series terminal fan. A controller determines the proper fan motor speed, and generates a control signal which is transmitted to the fan modulator for varying the volume of the fan to be at least equal to the volume of the primary air available.

Abstract: The variable air volume ventilating system includes a control device for driving a fan at continuously variable speeds for delivering air to the space for conditioning purposes. A controller monitors various conditioners of the space, to, in turn, cause the control device to drive the fan at different continuously varying speeds. A light conduit, such as a fiber optic link, interconnects the control device and the controller for supplying a control signal to the control device.