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.

Abstract: A pneumatic controller for use in controlling airflow in a conditioned air distribution system is adjustable to accommodate different types of damper actuation and thermostats in different systems. The four-function controller can be manually reconfigured to be a direct acting/direct reset controller, a reverse acting/reverse reset controller, a direct action/reverse reset controller or a reverse acting/directing resent controller, all using a single diaphragm valve responsive to differential pressure between total air and static air inputs. A reset unit on one end of the controller can be mounted in four different positions, two upright and two inverted, to provide the four functions, with total air and static air inputs being reversed in position when the controller is in a reverse acting mode. A differential pressure responsive valve at the heart of the system is controlled by a spring which can act as either a tension spring, for direct acting, or as a compression spring, for reverse acting.