Hussmann Corporation

Parker-hannifin Corporation

Ted Wayne Sunderland

Norman E Street

Doron Shapiro

Charles D Thomas

Michael J D'Anna

Dennis Doerr

Zachary R Wright

Dennis L Wagner

Dennis L Dickerson

Christian D Parker

Craig Steven Reichert

Craig Obermark

Dustin B Searcy

Nicolas G Sparacello

Kevin E Dorton

Patrick W Bundy

Dave P Wrocklage

Craig M Obermark

A fault tolerant interface includes a sensor and a safety control that are electrically connected to each other by a single wire. The sensor is configured to provide various signals to the safety control dependent on environmental parameters. Based on the ignal received by the safety control, the fault tolerant interface may act accordingly and place the overall system in a mitigative state in the event of a fault state or an alarm state. Data and fault or alarm states are detected by determining a first time interval between a first edge and a second edge of a signal, wherein an edge is one of a transition of the signal from a first voltage to a second voltage or a transition of the signal from the second voltage to the first voltage on a single wire. Data values versus fault or alarm states are assigned based on whether a current time interval corresponds to the first time interval or the second time interval, or another time interval associated with alarm or fault states.

Fault tolerant interface for safety controls

A control circuit includes a latching relay, a power loss activation circuit, and a watchdog circuit. A microcontrol unit (MCU) communicates with the watchdog circuit in a normal operation of the control circuit. As an action of a failsafe precaution in the event of a main power loss or a component failure, the MCU stops communicating with the watchdog circuit, at which point the watchdog circuit instructs the power loss activation circuit to continue operation of the control circuit. The control circuit further operates to implement mitigation operations in the event of a main power loss or component failure.

System and method for controlling a latching relay failsafe

A device, method and system is provided for regulating an ambient condition of a space via a heat exchanger that transfers heat energy from a secondary fluid to a primary fluid, and a flow control valve in fluid communication with the heat exchanger to vary a flow of the secondary fluid through the heat exchanger to provide a continuous flow of the secondary fluid between a minimum flow rate and a maximum flow rate. While in a first mode for regulating the ambient condition of the space, the flow control valve is modulated so as to provide variable and continuous flow of the secondary fluid through the heat exchanger to regulate the ambient condition to a desired target ambient condition. While in a pull-down mode for recovering after a defrost cycle of the heat exchanger, the flow control valve is modulated so as to provide variable and continuous flow of the secondary fluid through the heat exchanger to regulate a temperature drop of the secondary fluid across the heat exchanger.

Secondary fluid valve and system

A refrigeration system includes a compressor, a condenser, a receiver, an expansion device, and an evaporator in fluid communication with one another. An electronic condenser pressure control valve is in fluid communication with an outlet of the condenser and operative to control a condition at the outlet of the condenser. A controller is operatively coupled to the electronic condenser pressure control valve, the controller including logic configured to operate the electronic condenser pressure control valve to dynamically float the discharge pressure at the condenser outlet based on at least one of one or more system conditions or one or more ambient condition.

Indoor and outdoor ambient condition driven system

A commercial refrigeration system has a control system which distributes intelligence to increase granularity of the control and simplify wiring, assembly and installation. Compressors of the refrigeration system each have a bus compatible compressor safety and control module including a processor and sensors. All control and safety modules communicate over a single power and communications line with the controller, providing digital transmissions to the controller of measurements taken by the sensors. The information provided may include that the compressor is outside of a specific safety parameter, so that the controller knows not only that a safety parameter has been traversed, but exactly which one. The control and safety modules are capable of executing commands from the controller to cycle the compressors. The control and safety modules preferably contain sufficient intelligence to continue system operation upon failure of the controller. A compressor is also disclosed which has an intelligent control and safety module. The compressor also houses control and safety devices within a hermetically or semi-hermetically sealed shell. A condenser controller is also disclosed that is capable of communicating with the controller to affect intelligent control of one or more compressor fans.

Distributed intelligence control for commercial refrigeration

A display assembly for containing and displaying perishable products includes a case having at least one wall and defining an internal volume, a quantity of gas contained in the case, the gas including ethylene emitted from the perishable products, and an electro hydrodynamic thrust device positioned in the case. The electro hydrodynamic thrust device ionizes a portion of the quantity of gas. The ionized gas includes at least one reactive oxygen species, and the at least one reactive oxygen species reacts with the ethylene to break down the ethylene.

Electro hydrodynamic thruster for decontaminating a display case

A refrigerated merchandiser including a case that has a product display area for supporting food product, an opening for providing customer access to the product display area, and an air passageway in fluid communication with the product display area to direct an airflow into the product display area. The merchandiser also includes a door coupled to the case over the opening and including a charged glass pane, and a charge device in fluid communication with the air passageway to alter the polarity of the airflow to create a charged airflow. The charged glass pane and the charged airflow have the same polarity such that the glass pane is insulated from the charged airflow.

Refrigerated merchandiser with door having boundary layer

A merchandiser communication system including a first plurality of merchandisers arranged in a first row and a second plurality of merchandisers arranged in a second row. Each of the merchandisers includes a light assembly coupled to a case to illuminate a product display area, a light sensor coupled to the case to detect light pulses, and a microcontroller. The light sensor is in visual proximity with one or more of the adjacent merchandisers located across the aisle. The microcontroller is in electrical communication with the light assembly and the light sensor to operate the light assembly to encode the signal in light pulses of the light assembly that are not detectable by a human eye. The communication system also includes a visible light-based communication network in communication with the merchandisers and is operable to communicate the encoded light pulses among the merchandisers via the light assemblies and the light sensors.

Data communication for refrigerated merchandisers

An air sanitization system including a reactive oxygen species generator, a variable speed fan, a pathogen sensor and a controller. The reactive oxygen species generator generates reactive oxygen species from an oxygen-containing gas and discharges the reactive oxygen species to a conditioned space. The variable speed fan directs the oxygen-containing gas to the reactive oxygen species generator at a controlled speed. The pathogen sensor senses a level of airborne pathogens in the conditioned space and generates a signal indicative of the level of pathogens sensed. The controller receives the signal from the pathogen sensor and varies the speed of the variable speed fan in response to the signal to decrease a speed of the variable speed fan in response to an increase in the level of airborne pathogens sensed by the pathogen sensor.

Air sanitization system with variable speed fan

A method of operating a refrigerated merchandiser. The refrigerated merchandiser includes a case that defines a product display area, and at least one door that provides access to the product display area. The method includes sensing a parameter of an ambient environment adjacent the case, delivering a signal indicative of the sensed parameter to a controller, and determining a duty cycle using the controller based on the signal indicative of the sensed parameter. The method also includes detecting a change in the sensed parameter using the controller, interrupting the duty cycle by initiating a clearing interval using the controller in response to the controller receiving the signal indicative of the change in the sensed parameter, and clearing condensation from the door during the clearing interval.

Refrigerated merchandiser with glass door heat control

Methods, systems, and apparatus for linearizing control of a commercial refrigeration system. In an embodiment of the invention, a controller is configured to receive a non-linear sensed suction pressure and convert the suction pressure to a linear temperature equivalent. The linear temperature equivalent is used by the controller to achieve efficient system operation over an entire range of operating temperatures.

Methods and apparatus for linearized temperature control of commercial refrigeration systems

A system and method in a commercial refrigeration system for compensating for events. A commercial refrigeration system includes a controller that predicts a first change in cooling capacity required based on at least one anticipated system event. The controller also predicts a second change in cooling capacity required based on at least one anticipated system event during a period of time. The controller compares the first and second changes in cooling capacity and implements a change in cooling capacity based on a relationship between the first and second changes in cooling capacity.

Predictive capacity systems and methods for commercial refrigeration

A refrigeration system including a compressor, condenser, valve, and refrigeration branch, all of which is in fluid communication. The refrigeration branch includes an evaporator coil. The refrigeration system further includes a case adapted to be cooled by the evaporator coil, and a system controller operable to control one or more aspects of the refrigeration system, and a subsystem controller in communication with the system controller. The subsystem controller is operable to control a subsystem having one of the compressor, condenser, valve, refrigeration branch, and case. The method of operating the refrigeration system includes at the subsystem controller, monitoring a parameter of the subsystem, comparing the monitored parameter with a parameter limit, generating an alarm when the parameter is not within the parameter limit, and communicating the alarm to the system controller.

Refrigeration system and method of operating the same

A refrigeration system including an evaporator, a suction header in fluid communication with the evaporator, a compressor in fluid communication with the suction header, and a condenser in fluid communication with the compressor and the evaporator. The refrigeration system further including a controller operable to control the compressor and a sensor coupled to the compressor. The sensor is operable to acquire a parameter for the compressor. The method of operating the refrigeration system includes acquiring a value for the parameter with the sensor, and determining if the sensor is faulty.

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Troy, MO, United States of America

Ted Wayne Sunderland