Abstract:
Methods and Systems for controlling boiler systems are disclosed. In one illustrative embodiment, a derivative action control is used reduce the likelihood of overshoot from a newly activated boiler. When a newly activated boiler becomes active, the boiler is held at a low firing rate for a predetermined period of time. The predetermined period of time may be cut short or even entirely eliminated under certain conditions. The methods and devices are further adapted for use in multi-stage boiler systems. In one embodiment, only the first stage of a multi-stage boiler system that becomes active is held at the low firing rate.
Abstract:
An interoperable controller operation system having a command module or processor, and input and output interfaces. The command module may have an application that is fixed, configurable or programmable. The module may be changeable on the fly. The input and/or output interfaces may be changeable on the fly. The module or processor may have a memory or be connected to one. The processor and/or memory may contain a function block engine.
Abstract:
A variable velocity calibration and balancing system having a basis in a function block engine. It pertains to variable air volume systems and particularly to balancing systems as they relate to heating, ventilation and air conditioning (HVAC) systems. Balancing may be addressed using functional blocks to represent actual control and connections in an HVAC application for a variable air volume application.
Abstract:
An interoperable controller operation system having a command module or processor, and input and output interfaces. The command module may have an application that is fixed, configurable or programmable. The module may be changeable on the fly. The input and/or output interfaces may be changeable on the fly. The module or processor may have a memory or be connected to one. The processor and/or memory may contain a function block engine.
Abstract:
A system for optimizing usage of energy converting stages. It may have a stage driver, and stage driver adds as needed. The system may control the on-times of the stages according to a pattern that optimizes energy usage, processing and memory. The pattern may control the stages according to lead lag, rotating or runtime. The pattern may incorporate modulating. The system may be scalable and have a small memory footprint. The system may be implemented with function blocks of a function block engine. Network variables may be incorporated for input and output connections of the system.
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:
A method for controlling energy systems such as multiple boiler systems to meet an energy need includes a controller configured as a sequencer with the remaining controllers act as individual boiler controllers which periodically send status messages to the sequencer. The energy need is determined by measurements at the sequencer which maintains runtimes of the boilers. The sequencer periodically sends control commands to the boiler controllers to add or delete boilers. The control commands give consideration to the run times of the boilers.
Abstract:
A method for controlling a variable airflow apparatus to prevent processor overflow and underflow, with the variable airflow apparatus including an airflow sensor for providing an airflow sensor signal, a stored relationship between the airflow sensor signal and an airflow value, a damper for varying airflow, and an actuator for positioning the damper. The method includes energizing the airflow controller, determining either a minimum allowed airflow value based on the stored relationship between the airflow signal and an airflow value, or determining a maximum allowed airflow value based on the stored relationship, and periodically positioning the damper to provide an airflow value within a range limited by the minimum allowed airflow value or the maximum allowed airflow value in response to a signal from the airflow controller.
Abstract:
A method for operating a boiler including sensing a demand for heat and generating and ignition request to a flame safety controller. An ordered succession of evaluation modes compares normal operation to actual operation of control devices through the step of controlled ignition and transitions to a failure mode if an evaluation mode is not successfully completed. In addition, a series of status modes with each status mode being represented as an input condition are tested. A relative priority structure is established among the status modes and a unique message is associated with each status mode having an input condition that is true. Testing of the individual status modes proceeds in a predefined order until a status mode in a true condition is found and the unique message is displayed. In multiple boiler installations, a sequencer maintains a record of run times, determines an energy need and issues control commands to vary a firing rate or add or delete boilers giving consideration to the runtimes of the boilers.
Abstract:
Methods and devices for controlling multi-stage boiler systems. In one illustrative embodiment, the number of stages to be used is determined in a staging control sequence in response to a heating load, and in some cases, the individual stages are modulated to meet a heating load. In some embodiments, the staging control sequence may include observation of both heating load and the rate of change of the heating load. In another illustrative embodiment, the staging control compares a measured temperature to a setpoint and monitors changes in the measured temperature to make staging decisions. Various control methods are also provided to help achieve improved stability and efficiency, as desired.