Abstract: An integrated HVACR control and protection system includes a modular and reprogrammable design providing a plurality of possible combinations of power detection, voltage detection, run current detection, transient current detection, temperature detection, universal thermostat interface, peripheral or remote control, and local display and control. The control and protection system is capable of evaluating the relationship between real power used by an HVACR system compressor and other system operating parameters to detect problems early in the failure cycle, i.e., before a failure has progressed to requiring a system shutdown or causing damage to other components. Additionally, a control system and method provide sensorless detection of various HVACR system faults, such as, for example, loss of refrigerant or a refrigerant flow restriction, that impact the relationship between real power and current, voltage, temperature, or other operating parameters.

Abstract: The present invention provides a device and method for protecting the motor of a hermetic refrigeration compressor. The device comprises a motor, input power lines, and a motor protector connected to the input power lines to control the power to the motor. The motor protector includes a microprocessor, an input power measurement device, and a switch means for controlling the connection of the power lines to the motor. The input power measurement device includes a motor power input signal to the microprocessor. The microprocessor includes memory having instructions for storing an operating input power limit range based on the torque limits of the motor and for comparing the power input signal to the operating input power limit range of the motor. The microprocessor controls the switch means to open when the input power signal is outside of the operating input power limit range of the motor.

Abstract: A speed regulating governor system is disclosed for a small internal combustion engine having a throttle valve the position of which affects the speed of the engine, wherein the governor system includes a mechanical proportional controller and an electromechanical integral controller. The throttle valve is mechanically linked to and controlled by a governor lever that is acted upon by opposing forces provided by a mechanical speed selector and a centrifugal flyweight apparatus which measures the engine speed. Additonally, a solenoid actuator is operably connected to the governor lever to apply a force thereto in response to a control signal generated by an electronic integral controller. The control signal is proportional to the time integral of the difference between a desired electrical speed input and the actual speed of the engine measured by an electrical signal generated by an alternator driven by the engine.