Abstract: A motor control having mechanical switching and pressure reponsive components for connecting and intercepting a circuit between an A.C. source and an A.C. motor in response to pressure changes in a pressure system. The control includes a microcomputer chip and components that detect a voltage across the motor and a current through the motor and provide signals indicative of the level of the motor voltage and current. The control in response to the signals determines the power factor of the current and in response to the detected signals protects the motor from operating malfunctions when the voltage is too high or low, the current is too high or too low, the time of operation of the motor is too long or too short and in response to the character of the malfunction provides a visual coded lamp indication of the cause of the malfunction.

Abstract: A monitor for an electric motor, the monitor capable of connection to a supply of electrical energy for the motor, has a microcomputer for measuring the power factor of a voltage applied to the motor and a current flowing to the motor, for storing a desired value of power factor, for comparing a measured value of power factor with the desired value of power factor, and for disconnecting the motor from the supply of electrical energy if the measured value of the power factor differs from the desired value of power factor by an amount that exceeds a predetermined amount. Further, the monitor has means for operating the motor while driving a desired load; means for commanding the microcomputer to measure a power factor of the voltage applied to the motor and the current flowing to the motor while the motor is driving the desired load; and, means for storing the measured value of the power factor, measured while the motor is driving the desired load, as the desired power factor.