Abstract: This disclosure relates to a control system for driving a motor. The motor may include a cut-out circuit. The control system may include a buck-boost circuit to limit the rate of change of an output voltage before the output voltage is applied to operate the motor.

Abstract: A self-magnetizing motor incorporates a control circuit that starts the motor, controls a magnetizing unit, and then operates the motor. The control circuit can include relay, such as a bi-directional conductive power semiconductor device, and one or more PTC (Positive Temperature Coefficient) switches. This control circuit eliminates the need for a separate controller and the implementation costs can be reduced.

Abstract: A starting device and starting method for a single-phase induction motor, housing: a stator having a running coil and a starting coil; a running switch and a starting switch which is conducted to an open condition upon completion of the motor start. The starting device includes: a starting circuit including a control unit which receives, from a current sensor, signals representative of the current level being supplied to the stator, the control unit being connected to the running and the starting switches, for instruction the open and closed conditions thereof; the open condition of the starting switch being defined when the ratio between the present current level supplied to the stator and the starting current level, upon the closing of the starting and the running switches, reaches a predetermined value.

Abstract: An apparatus for controlling an operation of a compressor includes a controller for generating a control signal for selecting an operation mode of a compressor according to an operation load of the compressor; a first switching unit connected to a motor consisting of a main coil and a sub-coil and selecting the main coil or both the main coil and the sub-coil according to the control signal; first and second capacitors electrically connected with the first switching unit; and a second switching unit connected to the first capacitor and selectively connecting the first capacitor in parallel to the second capacitor according to the control signal.

Abstract: A method and system for estimating a temperature of an electric machine comprising obtaining a temperature value responsive to a temperature signal from a temperature sensor, the temperature sensor is operatively connected to and transmitting the temperature signal corresponding to a measured temperature to a controller. The controller executes a temperature estimation process; and is operatively connected to a switching device, where the switching device is operatively connected between the electric machine and a power source, the switching device being responsive to the controller. Also disclosed is a storage medium encoded with a machine-readable computer program code for estimating an operating temperature of an electric machine. The storage medium includes instructions for causing controller to implement method for estimating an operating temperature of an electric machine as described above.

Abstract: A motor starter for use with a motor (20) having a main winding (M) and a start winding (S). The starter has a PTC thermistor (30) connected in series with the start winding (S). A triac (40) is connected between PTC thermistor (30) and a power source line. A control circuit (50) is connected to the power source line for providing a voltage for a gate terminal (G) of triac (40) and an overload relay (60) is connected between the power source (10) and the motor (20). The control circuit (50) preferably includes a current detecting circuit (52) for detecting the inrush current and a voltage generating circuit (54) for generating the voltage in response to the detected inrush current. At the startup of motor (20) the control circuit (50) allows triac (40) to turn on by providing the gate terminal (G) with the voltage based on the inrush current. According to this invention, the power consumption of the start winding S after the startup of the motor (20) can be almost zero thus providing low power consumption.

Abstract: A starting device for electric motors which is designed to be fitted to compressor motors or the like, and includes a PTC resistor in series with a relay inserted between the line and the motor start winding.

Abstract: A motor start switch includes a temperature responsive resistor element and a cutout switch electrically connected in series with a start winding of an electric motor. The cutout switch is in thermal contact with the temperature responsive resistor element so that heat from the temperature responsive resistor element is transferred to a bimetal element in the cutout switch, causing the bimetal element to open the switch. Heat from a motor overload protector provides heat to maintain the bimetal element in an open position. As heat to operate the temperature responsive resistor element is obtained from existing circuit elements, the efficiency rating of the motor is unaffected.

Abstract: A motor starting device (1) has a thermostatic element (14) of a first switch circuit (11), a first resistive heater (13) serially connected to the first switch circuit, a thermostatic element (22) of a second switch circuit (21) and a second resistive heater (23) serially connected to the second switch circuit. The thermostatic element (22) of the second switch circuit is heated by both the first and second resistive heaters and, after actuation, is closer to the first resistive heater (13), thereby bringing the second switch circuit (23) into a de-energized state. When the second switch circuit (21) and the second resistive heater (23) are employed in the motor starting device, it becomes possible to provide a large electric current to the start winding during the start-up phase and to make the electric current that flows to the start winding zero after the start-up phase.

Abstract: Device for indicating the state of a single-phase asynchronous motor (MO) with a phase-shift capacitor, including an automatic stop switch (FC1, FC2) on each live conductor and a thermal switch (TH) on the return conductor, and the direction of rotation of which can be reversed by means of a changeover switch (CM). The indicator device consists of a current detector (DC), of a voltage detector (DT) and of processing logic (LT) respectively delivering information on the direction of rotation of the motor, the state of the live conductor switches and of the thermal switch.

Abstract: A split-phase starter for an electric motor having a casing made up of a casing body and a lid secured to the casing body, the casing body having a first casing and a second casing, a relay contact mechanism being arranged in the casing body, and a positive temperature coefficient thermistor being arranged in the second casing.

Abstract: A start circuit for a single phase AC induction motor employs an impedance in series with the run winding to develop a voltage drop proportional to the current through the run winding, and a pair of LEDs or another light emitting device across this impedance to produce a light output whose intensity varies with the field current, and hence in a generally inverse relation with motor speed. A solid-state AC current switch, which can be a triac or a pair of back-to-back SCRs, is gated by a photosensitive circuit that includes a photosensitive element. A light conduit, which can be a light pipe or light dome, for example, carries the light output from the light emitting element to the photosensitive element. The device of this circuit is highly reliable, has no mechanical contacts, and is relatively insensitive to temperature and voltage fluctuation.

Abstract: A shaded pole induction motor includes a plurality of series-connected running windings and a plurality of series-connected shaded pole coils (windings). A normally closed, centrifugal-force-responsive switch is provided in series with the shaded pole coils to effect an interruption in current therethrough when the motor reaches a predetermined speed. As a replacement to the normally closed switch, a switch constituted by a relay winding and normally open relay contacts may be provided, the contacts being in series with the shaded pole coils, these normally open contacts being closed in response to high initial starting current in the running windings flowing through a relay winding and being opened again when the motor gets up to a predetermined speed; less current flows in the relay winding and in the running windings under this condition. A heat-responsive circuit breaker may be placed in series with the normally open contacts or centrifugal-force responsive switch.

Abstract: This disclosure deals with a time delay cut-out circuit for the start winding of an AC electric motor. The circuit includes an electronic switch which is connected in series with the start winding and which may be selectively closed to energize the start winding. Time delay means is provided which, in response to current flow therethrough, provides a timing period. An auxiliary coil is inductively coupled to the motor windings and supplies current to operate the time delay means. The time delay means operates the electronic switch to energize the start winding during the timing period. The components of the circuit, except for the coil, are mounted in a capsule which may be plugged into the motor from the exterior of the stator. The time delay means includes a self heating, heat responsive device, and the components are sized and arranged to optimize the heat generation and dissipation properties and thereby obtain the desired operating characteristics.

Abstract: A combination relay-starter electrical device is adapted for connection in circuit relation with a winding circuit of a prime mover. The electrical device has a pair of terminal means adapted for the connection in the circuit relation with the prime mover winding circuit, and coil means adapted for electrical energization. Means arranged in magnetic coupling relation with the coil means is operable generally for switching between a circuit completing position and a circuit interrupting position upon the energization of the coil means, and means is provided for housing the terminal means, the coil means and the switching means. A solid state device associated with the housing means is connected in circuit relation between the switching means and one of the terminal means so as to be de-energized when the switching means is in its circuit interrupting position.Another electrical device is also disclosed.

Abstract: A combination starting and protecting device particularly useful with split phase motors such as those used with refrigeration compressors is disclosed in which an element of material having a positive temperature coefficient (PTC) of resistivity characteristic and a thermally responsive switch are disposed in the same housing. A thermal coupling of a preselected value between the PTC element and the thermally responsive switch is provided so that a desired reset or "off" time is obtained for the thermally responsive switch without affecting the "on" time.