Abstract: 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.

Abstract: A flow control device. The flow control device comprises a valve; an actuator operably connected to and positioning the valve and a controller operably connected to the actuator and providing control signals thereto. An external signal provides control input to the controller. A magnetically actuated sensor is operatively connected to the controller and provides a signal thereto in response to the movement of a magnetic field.

Abstract: A flow control device. The flow control device comprises a valve; an actuator operably connected to and positioning the valve and a controller operably connected to the actuator and providing control signals thereto. An external signal provides control input to the controller. A magnetically actuated sensor is operatively connected to the controller and provides a signal thereto in response to the movement of a magnetic field.

Abstract: 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.

Abstract: A system for electrically connecting electrical components. The system comprises a ribbon cable, a connector cap and a connector base. The connector cap includes a track area adapted to operably engage the ribbon cable, a cap alignment guide, and a cap orientation guide. The connector base has a first ribbon cable receptacle area adapted to electrically engage the first ribbon cable, a second receptacle area adapted to electrically engage a second ribbon cable, electrical interconnection means electrically interconnecting the first and second receptacles, first and second base alignment guides respectively positioned adjacent the first and second receptacle areas for alignment with the cap alignment guide, and a orientation receptacle operably positioned to receive the cap orientation guide.

Abstract: A flow control device. The flow control device comprises a valve; an actuator operably connected to and positioning the valve and a controller operably connected to the actuator and providing control signals thereto. An external signal provides control input to the controller. A magnetically actuated sensor is operatively connected to the controller and provides a signal thereto in response to the movement of a magnetic field.

Abstract: A system for electrically connecting electrical components. The system comprises a ribbon cable, a connector cap and a connector base. The connector cap includes a track area adapted to operably engage the ribbon cable, a cap alignment guide, and a cap orientation guide. The connector base has a first ribbon cable receptacle area adapted to electrically engage the first ribbon cable, a second receptacle area adapted to electrically engage a second ribbon cable, electrical interconnection means electrically interconnecting the first and second receptacles, first and second base alignment guides respectively positioned adjacent the first and second receptacle areas for alignment with the cap alignment guide, and a orientation receptacle operably positioned to receive the cap orientation guide.

Abstract: A method of controlling the operation of a centrifugal compressor in a water chiller system. The compressor's capacity is variable by modulating its speed of rotation or by modulating its inlet guide vane's position. The water chiller includes an evaporator having a leaving water temperature. The method comprises the steps of: monitoring the leaving water temperature; determining if the leaving water temperature is in a steady state; modulating the compressor capacity by modulating speed of rotation if the leaving water temperature is in a steady state; and modulating the compressor capacity by modulating inlet guide vane position if the leaving water temperature is not in a steady state.

Abstract: A method of controlling the operation of a centrifugal compressor in a water chiller system. The compressor's capacity is variable by modulating its speed of rotation or by modulating its inlet guide vane's position. The water chiller includes an evaporator having a leaving water temperature. The method comprises the steps of: monitoring the leaving water temperature; determining if the leaving water temperature is in a steady state; modulating the compressor capacity by modulating speed of rotation if the leaving water temperature is in a steady state; and modulating the compressor capacity by modulating inlet guide vane position if the leaving water temperature is not in a steady state.

Abstract: A controller for controlling the capacity of a centrifugal chiller compressor. The compressor is driven by an electric motor and has variable inlet guide vanes that control the flow of refrigerant to the compressor. The controller establishes a dimensionless plot of possible points of compressor operation relating the pressure coefficient and the capacity coefficient of the compressor. The current operating point of the centrifugal compressor is located on the plot and a dynamic surge boundary control curve is positioned proximate a region of actual surge. Control is exercised responsive to the variations of the region of actual surge and the surge boundary control curve for controlling compressor capacity by varying the opening of the inlet guide vanes and varying the speed of the compressor to move the operating point of the compressor proximate the surge boundary control curve.

Abstract: 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.

Abstract: A method of protecting the compressor motor of a refrigeration system using a multiphase AC power source. The method comprises the steps of monitoring each phase of the power supply to the compressor motor; calculating the average phase for the phases of the AC power supply; determining a maximum phase unbalance deviation from the average phase; determining if a first level of phase unbalance protection is active; setting a system protection level as the first level of phase unbalance protection if the first level is active; setting the system protection level as a second higher level of phase unbalance protection if the first level is not active; and initiating a compressor motor shutdown if the system protection level is exceeded by the maximum unbalanced phase deviation.

Abstract: The determination as to whether an operational compressor in a multiple-screw compressor water chiller is fully loaded is made by sending a relatively long duration test pulse to the load solenoid of the compressor. If the compressor is fully loaded, no measurable change in the current drawn by the compressor motor will be measured since no slide valve movement will have occurred and no additional load will have been placed on the compressor. If, however, the compressor is not fully loaded at the time the test pulse is sent, the compressor slide valve will move to load the compressor to an extent such that a reliably measurable change in compressor motor current draw occurs.

Abstract: 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.

Abstract: A temperature control is disclosed for a variable volume air conditioning system of the type wherein electric motor-operated air valve means are provided for varying the volume of relatively warm or relatively cool conditioned air supplied to a conditioned zone. The control includes zone thermostat means for sensing the temperature within a conditioned zone, determining the deviation between a set-point temperature and the zone temperature, and for producing an electrical error signal having a magnitude which varies in a predetermined relationship with respect to said deviation in temperature. Valve motor control circuit means receive the error signal and are operative to energize electric motor-operated air valve means in response thereto so as to vary the volume of conditioned air being supplied to said conditioned zone in a sense to restore the zone temperature to the set-point temperature.

Abstract: A temperature control is disclosed for a variable volume air conditioning system of the type wherein electric motor-operated air valve means are provided for varying the volume and relatively warm or relatively cool conditioned air supplied to a conditioned zone. The control includes zone thermostat means for producing an electrical error signal having a magnitude which varies in a predetermined relationship with respect to a deviation in zone temperature, and changeover circuit means for varying said predetermined relationship in order to accommodate changeover between heating and cooling, as sensed by duct temperature sensing means. The control further includes flow limit circuit means for imposing limits upon the maximum and minimum desired flow of conditioned air through the air valve means.

Abstract: Apparatus are disclosed for sensing the velocity of a fluid stream, as may be flowing in a duct, pipe, or the like, which fluid stream exhibits variations in its temperature under different operating conditions. The apparatus includes a first probe which is exposed to the fluid stream and includes first temperature sensing means for sensing the temperature of the fluid stream. A second probe is provided which is disposed within the fluid stream and includes at least a portion constructed of a thermally conductive material. Heater means are disposed in thermally conductive relationship with said thermally conductive portion, and second temperature indicative of the temperature of said heater means. Third temperature sensing means are provided for sensing the temperature of the thermally conductive portion of the second probe at a point removed from the heater means, which temperature is a function of the heater means temperature, the fluid temperature, and the velocity of the fluid flowing thereover.