Abstract:
Fan coil thermostats can provide energy savings by, for example, operating a fan coil system more efficiently. Fan coil systems employing such a fan coil thermostat may be more energy efficient. A fan coil system may include a fan coil that is configured for fluid communication with a source of heated fluid and/or a source of cooled fluid, a valve that controls fluid flow through the fan coil and a fan that blows air across the fan coil. The fan coil thermostat may include a controller that implements a control algorithm that calculates an error percentage value relating to a temperature difference between the current temperature and the temperature set point. The error percentage value may include a proportional term related to the temperature difference and an integral term related to the temperature difference. The controller may regulate the fan speed in accordance with the calculated error percentage.
Abstract:
An electronic device such as an HVAC controller that accounts for internal heating in determining an environmental condition such as temperature or humidity in the space surrounding the HVAC controller. The HVAC controller may calculate a transient heat rise value that is based upon a powered time period and a first order time lag, especially during a time period before which the HVAC controller reaches a steady state temperature condition.
Abstract:
An actuator system which may incorporate a motor, a motor controller connected to the motor, a processor connected to the motor controller, and a switch connected to the processor for engaging the motor to open and close an actuator shaft. The switch may have a position which is a test mode. Selecting the position of test mode may cause the motor to move the actuator shaft to a certain position to verify operation of the actuator shaft. The actuator shaft may stay in the certain position while the switch is in a position of test mode. The system may also incorporate a spring attached to the actuator shaft. If power fails to the motor, then the actuator spring or another mechanism may return the actuator shaft to a fail safe position. The test mode may alternatively be selected at a controller via the communications bus to the processor.
Abstract:
An approach to automatically encode application enumeration values to enable reuse of applications across controller of different protocols. Protocols may use different sets of enumerations to denote various application values and states. The present approach may permit defining a common set of enumerations which can be encoded automatically by a tool that enables reuse. Application designers may define enumerations to be used by the control application and the tool will automatically encode them into communication protocol specific enumeration values.
Abstract:
An actuator system which may incorporate a motor, a motor controller connected to the motor, a processor connected to the motor controller, and a switch connected to the processor for engaging the motor to open and close an actuator shaft. The switch may have a position which is a test mode. Selecting the position of test mode may cause the motor to move the actuator shaft to a certain position to verify operation of the actuator shaft. The actuator shaft may stay in the certain position while the switch is in a position of test mode. The system may also incorporate a spring attached to the actuator shaft. If power fails to the motor, then the actuator spring or another mechanism may return the actuator shaft to a fail safe position. The test mode may alternatively be selected at a controller via the communications bus to the processor.
Abstract:
A system having a function block execution framework. Function blocks may be for use in a control system design. These blocks may be selected from a library of a function block engine. Selected function blocks may be executed for operational purposes. They may be continuously executed by a processor to maintain operational status. However, since a function block engine and a resulting system of function blocks may be operated with battery power, executions of function blocks may be reduced by scheduling the executions of function blocks to times only when they are needed. That means that the processor would not necessarily have to operate continuously to maintain continual execution of the function blocks and thus could significantly reduce consumption of battery power.
Abstract:
A function block engine, a block execution list and a parameter and/or variable storage space being resident in a memory supporting the engine. The function block engine may execute a program according to a list of function blocks identified in the block execution list to design and construct and circuit or system. Also, the engine may provide simulation of the resultant circuit or system. The circuit or system may be transferred to a memory of another device for implementation and use as, for example, a controller. In some cases, the program may be executed from the memory. The engine may permit field programmability, configuration and simulation of the function blocks and resulting circuit or system.
Abstract:
Methods and apparatus for more effectively managing humidity of an inside space using an air conditioner are provided. In one illustrative embodiment, the system determines whether the humidity level in an inside space is above a predetermined humidity threshold, and if so, changes a control parameter such as a minimum “on” time for the air conditioner. If the humidity level in the inside space is not above the predetermined humidity threshold, the control parameter is not changed, or changed less than when the humidity level is above the predetermined humidity threshold. Rather than changing (i.e. increasing) the minimum “on” time, it is contemplated that any control parameter that increases the “on” time of the air conditioner may be used including, for example, changing (i.e. decreasing) the maximum cycle rate allowed for the air conditioner.
Abstract:
Methods and systems for automatically calibrating one or more damper positions of a demand control ventilation system are disclosed. In one illustrative embodiment, a demand control ventilation system includes a damper for controlling a flow of outside air into a building. A controller may be programmed to automatically execute a calibration algorithm from time to time to calibrate one or more calibration damper positions such that a predetermined flow of outside air is drawn through the damper and into the building at each of the one or more calibration damper positions. This calibration can, in some instances, help increase the efficiency and/or utility of the demand control ventilation system.
Abstract:
The present disclosure provides a method for operating an HVAC system for conditioning air of an inside space. The HVAC system has an economizer configured to control the intake of outside air into an HVAC air stream of the HVAC system. The method includes determining at least two parameters of the air of the inside space, where the at least two parameters are selected from a set of parameters from which an inside air dry bulb temperature, an inside air dew point, an inside air relative humidity, and an inside air enthalpy can be determined, either directly or indirectly. The method also includes determining at least two parameters of the outside air, where the at least two parameters being selected from a set of parameters from which an outside air dry bulb temperature, an outside air dew point, and an outside air enthalpy can be determined, either directly or indirectly. Based on one or more of the inside air dry bulb temperature, the inside air dew point, the inside air relative humidity, and the inside air enthalpy, a determination is made of whether dehumidification of the inside space is needed, and if dehumidification is not needed, the economizer is commanded to increase the intake of outside air into the HVAC air stream if the outside air dry bulb temperature is less than a dry bulb temperature reference, and if the outside air enthalpy is less than an enthalpy reference. If, alternatively, dehumidification is needed, the economizer is commanded to increase the intake of outside air into the HVAC air stream if the outside air enthalpy is less than the enthalpy reference, and if the outside air dew point is less than a dew point reference.