American Standard Inc.

Trane International Inc.

Merle A Renaud

Paul C Rentmeester

Joe M Baldwin

Doyoung Han

Dennis R Dorman

Thomas J Clanin

Robert E Krocker

Robert M Swanson

Richard A Bishop

Terence D Baier

Robert L Oltman

James A Davis

Brian S Junk

Paul F Haley

Alan G Metcalfe

Patrick J Wilson

Kirk W Johnson

A system for servicing a computer controlled machine comprising: a computer controlled machine including a device operable to perform a function, a controller controlling the operation of that device, and a data access port for transferring data and commands from the controller; and a service tool operably connected to the data access port, the service tool including a remote communications capability, a computer, and diagnostics and graphing software; and an expert observer system operably linked to the remote communications capability of the service tool and including historical machine data, machine sales information, software revisions for the controller, additional diagnostics software, and an expert observer capable of providing a mentor capability to the operator of a service tool.

HVAC service tool with internet capability

A method of configuring a controller of an HVAC system comprising the step of configuring the HVAC system based upon components which are indicated by a wiring harness to be physically connected to the HVAC system.

Configuration wiring harness for HVAC controller

A method of controlling a multiplicity of condenser fans in a refrigeration system comprising the steps of: calculating a first difference in state between a high pressure side and a low pressure side of the refrigeration system; determining an optimum state for the refrigeration system; determining a second difference in state between the first difference and the optimum difference; and controlling the multiplicity of condenser fans if the second difference exceeds a predetermined value.

Condenser fan control system for use with variable capacity compressor

An interface for use between a thermostat and a controller for an HVAC system comprising: means for receiving a plurality of parallel commands from a thermostat where each command represents one of two possible states; means for coverting each of the plurality of parallel commands into a plurality of predetermined values; means for combining the predetermined values in a predetermined manner; and means for transmitting the combined predetermined values to the controller.

Thermostat interface for a refrigeration system controller

A control and method for varying the capacity of a centrifugal chiller system used to cool a liquid to a setpoint temperature. The control permits the user to select the setpoint, the control gain, and two variables that determine a first deadband and a second relatively wider deadband about the setpoint. If the absolute value of the difference (error) between the actual fluid temperature and the septoint is increasing, the control uses the first deadband, and conversely, if the error is decreasing, it uses the second deadband to vary chiller capacity. The control also permits the user to select a limit for various operating parameters associated with protective shutdown of the system to avoid catastrophic failure, and adjusts the chiller capacity according to one of two predefined functions of the deviation of the operating parameter from its limit, dependent on whether that deviation is greater or less than a predefined deadband.

Control and method for modulating the capacity of a temperature

A control and method for varying the capacity of a centrifugal chiller system used to cool a liquid to a setpoint temperature. The control permits the user to select the setpoint, the control gain, and two variables that determine a first deadband and a second relatively wider deadband about the setpoint. If the absolute value of the difference (error) between the actual fluid temperature and the setpoint is increasing, the control uses the first deadband, and conversely, if the error is decreasing, it uses the second deadband to vary chiller capacity. The control also permits the user to select a limit for various operating parameters associated with protective shutdown of the system to avoid catastrophic failure, and adjusts the chiller capacity according to one of two predefined functions of the deviation of the operating parameter from its limit, dependent on whether that deviation is greater or less than a predefined deadband.

This controller is used for controlling a centrifugal compressor along its path of minimum power consumption while avoiding a surge condition. It is especially useful in a refrigeration system having a variable speed centrifugal compressor with adjustable inlet guide vanes. In such an application, the controller opens the inlet guide vanes enough to satisfy the cooling demand and then, to minimize power consumption, reduces the speed of the compressor while further opening the vanes (compensating for the reduced speed) until either the inlet guide vanes are fully open or an impending surge condition is detected. The onset of a surge condition is detected by monitoring motor current fluctuations. When fluctuations above a predetermined amplitude occur in excess of a predetermined frequency, the controller determines that a surge is impending. The controller continues to control the compressor in this manner, providing a capacity that is minimally above a level that would cause a surge yet is sufficient to satisfy the cooling demand.

Growing community of inventors

Onalaska, WI, United States of America

Merle A Renaud