Abstract: The present invention discloses methods for determining setpoint information in a HVAC system. Setpoint values are determined using occupant feedback provided by individual occupants over at least one of an Internet or Intranet communications network. According to a first aspect of the invention a setpoint is determined using fuzzy logic. According to a second aspect, historical setpoint data determined using occupant feedback is used to develop a neural network for predicting setpoint values.

Abstract: A controller for heating, ventilating and air-conditioning distribution systems, which includes feedforward and feedback control strategies. The controller has a feedforward control strategy that generates a control signal based on control set points and identified characteristics of the system, and which adaptively adjusts such set points based on changes that are measured with respect to the identified characteristics. The controller is particularly adapted for controlling the temperature during a heating or cooling operation in a controlled space.

Abstract: A controller for heating, ventilating and air-conditioning distribution systems, which includes a feedforward and feedback control strategies. The controller has a feedforward control strategy that generates a control signal based on control set points and identified characteristics of the system, and which adaptively adjusts such set points based on changes that are measured with respect to the identified characteristics. The controller is particularly adapted for controlling the differential air pressure in a controlled space relative to adjacent spaces.

Abstract: A HVAC system automates the process of calibrating the individual branch flows of the system. For each branch of the system, a damper is closed and flow values at the output of the prime mover and at the input of the damper are measured. The damper is then opened 50% and again flow values at the output of the prime mover and at the input of the damper are measured. A flow coefficient, which correlates the flow difference measured at the output of the prime mover with the flow difference measured at the input of the damper, is then determined. The flow through each damper of each branch is calibrated in this manner, resulting in an overall balancing of the HVAC system. The automated process of branch flow calibration eliminates the tedious and time consuming process of both manual steps of measuring the branch flows and determining the flow coefficients as was performed in the prior art.

Abstract: A controller implemented in a heating, ventilation and air-conditioning (HVAC) distribution system provides improved control by implementing a general regression neural network to generate a control signal based on identified characteristics of components utilized within the HVAC system. The general regression neural network utilizes past characteristics and desired (calculated) characteristics to generate an output control signal. The general regression neural network is implemented in a feedforward process, which is combined with a feedback process to generate an improved control signal to control components within the HVAC distribution system. Implementation of the general regression neural network is simple and accurate, requires no input from an operator supervising the controller, and provides adaptive, real-time control of components within the HVAC distribution system.

Abstract: A global control system is implemented in a heating, ventilation and air-conditioning (HVAC) distribution system. The system allows local controllers and a source controller to exchange data between one another so that optimization of control for a local component is not sacrificed for optimization of control for a source component, and vice versa. The controllers have their control process sudivided into an identification process and a control process. The identification process periodically identifies characteristics related to the component to be controlled. The control process continuously generates a control signal to be applied to the component to control the component. The control process is further subdivided into a feedforward process and a feedback process. The feedforward process utilizes the identified characteristics to generate a control signal based on calculated system variables, while the feedback generates a control signal based on measured system variables.

Abstract: A controller controls a prime mover (source component) in a heating, ventilation and air-conditioning (HVAC) distribution system. The controller determines a static pressure setpoint for the source component by first determining the pressure loss of each branch throughout the system. The controller then determines the pressure loss contributed by local components located within each branch of the system. The maximum of the branch pressure losses and the maximum of the component pressure losses are summed to provide the static pressure setpoint for the source component. The method provides control of the prime mover independent of the configuration of the system.

Abstract: Fume hood controller apparatus includes a computing means, together with associated memory, which can be configured for horizontally and/or vertically moveable sash doors by inputting the necessary dimensions of the sash doors and other structural features, such as the upper lip height, frame widths and the like. The apparatus rapidly calculates the size of the uncovered area of the fume hood as a functions of the position of the sash doors.

Abstract: A system whereby the pressure of a room containing one or more fume hoods, such as a laboratory, is to maintained at a predetermined level relative to the pressure of a reference space in the building, which may be the pressure in an adjacent corridor or an adjacent room or the like. The system involves a room controller which is part of the heating, ventilating and air conditioning apparatus of the building. The room controller is of the type which can receive electrical signals from each fume hood controller, which signals are proportional to the volume of air that is being exhausted through each fume hood. The volume indicating signals communicated from each of the fume hood controllers to the room controller enable the system to modulate the volume of air that is being supplied to the room and thereby maintain the differential pressure at the desired level with relatively quick response times.

Abstract: Apparatus for controlling the air flow through a fume hood to maintain a predetermined average face velocity through an uncovered portion of an opening of a fume hood of the type which has at least one movable sash door adapted to cover the opening as the fume hood sash door is moved. The apparatus detects the position of each moveable sash door and calculates the size of the uncovered portion of the opening, measures the actual flow of air through the exhaust duct, and varies the flow of air through the exhaust duct responsive to door position signals and the actual flow signal for controlling a flow modulating means to maintain the predetermined average face velocity through the uncovered portion of the opening.

Abstract: A fume hood controlling apparatus that provides desirable operational safety features for persons who use the fume hoods to perform experiments or other work. The apparatus is adapted for use with fume hoods that have a filtering means lcoated between the fume hood enclosure and the exhaust duct. The apparatus determines if a filter medium is loaded beyond a predetermined amount. The apparatus also provides a visual or audible indication in response to the detected loading. The apparatus also has emergency switches near each fume hood, with the switch controlling the fume hood when actuated so that the fume hood can operate in an emergency mode, and also providing an indication to a central building console of a building supervisory and control system for heating ventilating and air conditioning apparatus.