Abstract: A liquid refrigerant drainage mechanism is described for use in a flooded evaporator to mitigate liquid carryover. The drainage mechanism can trap liquid refrigerant droplets, create a liquid column to overcome a pressure difference across the mechanism and drain liquid back to the pool in the evaporator. The drainage mechanism is disposed in a suction baffle, and has a mesh pad and a tapered pipe secured to the bottom of the baffle. The pipe has a drainage aperture at one end to allow the accumulated liquid refrigerant to return to the refrigerant pool below. The mesh pad helps to separate liquid droplets that coalesce and fall into the tapered pipe. By using this liquid drainage mechanism in conjunction with a suction baffle, liquid carryover can be reduced and chiller performance improved.

Abstract: A vehicle electrical system for supplying a first load with a first direct current voltage and for supplying a second load with a second direct current voltage lower than the first direct current voltage is disclosed.

Abstract: The flow air from a hot air duct and a cold air duct into a zone of a building is controlled in based upon performing a thermal energy balance calculation for the zone. That calculation produces a heat transfer setpoint from which a hot air flow setpoint and a cold air flow setpoint are derived. The hot and cold air flow setpoints respectively control the flow of air through the hot and cold air ducts.

Abstract: A method for controlling non-synchronous actuators using a first and second estimate of the position of the actuator to create a variable position estimate window between which the actual position of the actuator is always bound. The first and second estimates of position are calculated based on the maximum and minimum speeds at which the actuator could be moving in each of first and second directions, and further wherein motion of the actuator in a saturated direction is disabled for as long as the first and second estimates converge at one of two final positions.

Abstract: A computer-implemented building automation operating system for supporting applications that interact with building automation devices in different locations. A computer-human interface is provided for viewing data related to the applications. A master name data structure stores global identifiers and location specific names for each of the applications that interact with the building automation devices. The global identifiers uniquely identify the applications. A building automation master name processor is connected to the master name data structure and to the computer-human interface for providing to the computer-human interface a location specific name based upon its associated global identifier. These features significantly enhance the global distribution and use of new building automation software applications.

Abstract: A humidity detector has a sensor with an electrical characteristic that varies as a function of humidity and a transmitter circuit which produces an output signal in response to the capacitance of the sensor. The humidity detector is calibrated by alternately connecting devices in place of the sensor which simulate performance of the sensor at two reference humidity levels. While each device is present, the transmitter circuit is adjusted so that the output signal indicates the respective reference humidity level. Next, the sensor is connected to the transmitter circuit and exposed to a known humidity level. Then the transmitter circuit is adjusted so that the output signal indicates the known humidity level.

Abstract: The present method defines a plurality of individual temperature sensor cells on a single printed circuit board with a separate temperature detector mounted in each cell. The temperature response of each detector is characterized substantially simultaneously and the values for series and parallel trimmer resistors for each cell are determined from the temperature response of the detector for the cell. Then an automated machine attaches properly valued resistors in parallel and in series with each detector on the printed circuit board.

Abstract: Fault detection is implemented on a finite state machine controller for an air handling system. The method employs data, regarding the system performance in the current state and upon a transition occurring, to determine whether a fault condition exists. The fault detection may be based on saturation of the system control or on a comparison of actual performance to a mathematical model of the air handling system. As a consequence, the control does not have to be in steady-state operation to perform fault detection.

Abstract: The present invention provides a sequencing control strategy for environmental system controllers that takes better advantage of the capabilities of the system elements to enhance performance and reduce operating costs. A state machine controller is implemented by employing digital technology which enables greater accuracy in monitoring system performance and performing diagnostics. This control modality also provides greater tolerance of faults by permitting automatic reconfiguration of the control strategy so as to be independent of malfunctioning components.

Abstract: An actuator is operated to move a mechanical device between two extreme positions of travel. While that motion is occurring, the system quantifies the amount of movement that occurs between those positions. The quantification may involve counting the number of steps of a stepper motor. The number of steps may be used directly as a quantification. Alternatively, the number of steps can be multiplied by the time period of each step to derive the time of the movement between the extreme positions. In addition to being used to setup the actuator upon installation, this automatic ranging method can be performed periodically to compensate for effects of wear on the mechanical device.

Abstract: A computer-implemented building automation system is provided with an asynchronous communication architecture for supporting object-oriented applications that interact with distributed building automation devices. Standard application objects which need to be informed of changes to the value of another object's attributes use a connection object to establish an asynchronous link between standard objects. A source object has a control attribute that changes based upon the execution of this object's control method which in turn is linked to a second control attribute of a destination object. By linking these attributes, a connection object is defined to manage information being passed between these two objects. Upon instantiation of the connection object, it registers the second control attribute with the source object to receive "significant" changes in the value of its control attribute.

Abstract: An improved vent cap system for use in an electrochemical battery is provided which includes a ring flange for forming a ring seal between the vent cap assembly and the fill tube. When the vent cap assembly is positioned in the battery housing, the ring flange and the fill tube deform to create a seal therebetween to provide a fluid tight seal.

Abstract: An electrical switch has a snap action blade with a contact pad. The snap action blade toggles between a first configuration at which the contact pad abuts a stationary contact and a second configuration at which the contact pad is remote from the stationary contact. An actuator moves the snap action blade between the first and second configurations. A reset spring has a first position which biases the movable contact into one of the first and second configurations, and has a second position at which that biasing does not occur. A reset selector acts to determine whether the reset spring is in the first or second position. A manual reset actuator is provided to move the snap action blade into the one of the first and second configurations when the reset spring is in the second position. Operation of the reset selector selects whether the switch is in an automatic reset mode or a manual reset mode.

Abstract: An thermal storage system controller implements a near optimal control strategy for minimizing energy and demand costs. A system performance variable is determined and evaluated under a given set of environmental conditions for selecting one of a plurality of control strategies.