Abstract: A compressor includes a motor protector which stops the compressor motor when it senses an out of specification condition. A diagnostic system monitors the status of the motor protector and includes logic circuitry that diagnoses the type of problem the compressor or the system is having based upon the running times and status of the motor in conjunction with the times and status of the tripped motor protector. The diagnostic system also includes either a discharge pressure sensor or a condenser temperature sensor, an ambient air sensor and a voltage sensor. The sensors provide information to the diagnostic system, which enable it to determine where a system fault has occurred.

Abstract: A starting and protection device for refrigerator motors having a thermal protection device and a PTC resistor, includes a common casing containing the protector and the PTC resistor. The casing is formed by two separate bodies designed to house the protector and the PTC resistor respectively. The bodies are separate and distanced to prevent the protector from being affected by the heat developed by resistor.

Abstract: A system and method for diagnosing and protecting a compressor includes a sensor, logic circuitry, a motor protector and an intelligent device. The logic circuitry is associated with the sensor and the motor protector and operable to determine a trip frequency of the motor protector and identify a specific fault cause. The intelligent device communicates with the logic circuitry and indicates the fault cause.

Abstract: A method includes determining base-line operating parameters for a compressor, generating a high-side signal indicative of high-side compressor operating conditions, generating a low-side signal indicative of low-side compressor operating conditions, and comparing the high-side and low-side signals to the base-line operating parameters to determine a system operating condition.

Abstract: A compressor assembly comprises a compressor, a motor protector, and a signaling device. Upon an overload condition, the motor protector activates. The signaling device also activates to serve as an alert that the compressor is not malfunctioning but instead is in an overload condition.

Abstract: A method of operating a climate control system includes generating a signal based upon the operation of the compressor, and controlling the compressor in response to the generated signal. A climate control system implementing the method includes a compressor, and module for generating at least one signal based upon the operation of the compressor, and a thermostat for controlling the compressor, the thermostat controlling the compressor in response to signals generated by the module. A system for controlling a compressor in a climate control system implementing the method includes a module that generates signals relating to the operation of the compressor, and a thermostat, responsive to the module, for controlling the compressor. A thermostat for controlling a climate control system having a compressor implementing the method operates the compressor in response to at least one signal representative of the operation of the compressor.

Abstract: In an apparatus and a method for detecting a phase state capable of improving reliability of an air conditioner by preventing an abnormal operation of the air conditioner by detecting a phase state (antiphase and open-phase) of three phase AC power supplied to the air conditioner and displaying the detected phase state, the apparatus includes a phase detector for detecting first, second and third phases of a three phase current; an interrupt detector for detecting a falling edge of a pulse signal corresponded to the third phase of the detected first, second and third phases, recognizing an interrupt occurrence by the third phase when the falling edge is detected and generating a counting signal; a counter for counting a pulse signal corresponded to the first and second phases on the basis of the interrupt occurred-third phase according to the counting signal; an antiphase/open-phase detector for detecting a state as a normal connection state, an antiphase state on the basis of a pulse signal corresponded to t

Abstract: A protective device includes a signal input intended for connection to a sensor, a signal output intended for connection to an evaluation unit, and an isolation element for galvanically separating the signal input from the signal output. The provision of the protective device prevents a transmission of overvoltages from the sensor to the evaluating unit.

Abstract: In regenerative braking mode, an inverter converts, according to PWMC signal from a control unit, an AC voltage generated by a motor into a DC voltage to supply the converted DC voltage to an up-converter which down-converts the DC voltage to charge a DC power supply. The control unit receives voltage V2 from a voltage sensor to stop the up-converter if voltage V2 is higher than a predetermined value. The control unit further receives voltage Vf from a voltage sensor that is applied to a DC/DC converter and stops the up-converter if voltage Vf is higher than a predetermined value. Moreover, the control unit receives voltage V1 of the DC power supply from a voltage sensor to stop the up-converter if voltage V1 does not match voltage V2.

Abstract: A system for detecting loss of an electrical phase in a compressor system includes a compressor system component having a plurality of phase carrying legs; a sensor for measuring current communicated with one leg of the plurality of phase carrying legs; and a processor unit adapted to receive a signal from the sensor and determine whether loss of phase has occurred in any of the plurality of phase carrying legs.

Abstract: A controlling device of a compressor is provided. A noise filter is arranged at an input of the inverter circuit that converts the commercial frequency to a driving frequency to control a motor driving a compressor mechanism, for suppressing a common mode noise of the commercial power source and the inverter circuit, and is connected to a ground through a metal frame used for receiving a compressor main body. The noise filter comprises coils connected between first capacitors and second capacitors that are connected in series between the AC power lines, and further comprises a clamper connected between nodes of the second capacitors and the metal frame for clamping a voltage and a third capacitor connected to the clamper in parallel. even though the new refrigerant, such as R410A, and the three-phase AC power source are used, the leakage current can be reduced by a simple structure and the increase of the noise terminal voltage can be also suppressed.

Abstract: A cooling system includes a compressor having a motor protector which stops the compressor's motor when it senses an out of specification condition. A diagnostic system of the cooling system monitors the status of the motor protector. The diagnostic system includes logic circuitry that diagnoses the type of problem the compressor or the system is having based upon the running times and status of the motor in conjunction with the times and status of the tripped motor protector. The diagnostic system also includes either a discharge pressure sensor or a condenser temperature sensor, an ambient air sensor and a voltage sensor. The sensors provide information to the diagnostic system to enable it to determine and indicate a system fault.

Abstract: A refrigeration/air conditioning system includes a compressor having a motor protector which stops the compressor's motor when it senses an out of specification condition. A diagnostic system of the refrigeration/air conditioning system monitors the status of the motor protector. The diagnostic system includes logic circuitry that diagnoses the type of problem the compressor or the system is having based upon the running times and status of the motor in conjunction with the times and status of the tripped motor protector. The diagnostic system also includes either a discharge pressure sensor or a condenser temperature sensor, an ambient air sensor and a voltage sensor. The sensors provide information to the diagnostic system which enables it to determine where a system fault has occurred.

Abstract: A compressor terminal fault interruption method and interrupter for disconnecting power to a compressor terminal when terminal venting failure is imminent including a current sensing circuit for sensing current provided to the terminal by a power source and outputting a sensed signal representing the current provided to the terminal and a control circuit. The control circuit includes a first circuit for outputting a reference signal representing input current much higher than locked rotor current, a second circuit connected to the current sensing circuit and the first circuit for comparing the sensed signal to the reference signal, and a third circuit connected to the second circuit for disconnecting power to the terminal when the sensed signal exceeds the reference signal, thereby preventing excessive current from reaching the compressor terminal.

Abstract: An inverter apparatus includes an inverter for driving a 3-phase motor, a power supply circuit for applying direct current voltage to the inverter, a switching element mounted above and below an arm of each phase, a smoothing capacitor for protecting a voltage applied to the inverter from reaching a value equal to or larger than a predetermined value, and a control circuit for generating a control signal for control of an ON/OFF switching operation of each switching element. The control signal is generated by the control circuit such that the ON timing of each switching element of each phase can be shifted from each other.

Abstract: A system for detecting loss of an electrical phase in a compressor system includes a compressor system component having a plurality of phase carrying legs; a sensor for measuring current communicated with one leg of the plurality of phase carrying legs; and a processor unit adapted to receive a signal from the sensor and determine whether loss of phase has occurred in any of the plurality of phase carrying legs.

Abstract: A device for control of a compensator (SVC), connected to a polyphase electric transmission network (NW), for reactive electric power in dependence on a voltage (Vabc) sensed in the transmission network has a voltage controller (7, 8) which, in dependence on the difference of a reference value (V, ref) for said voltage and its sensed value, forms a reference value (QCR) for a reactive power flow (QC) through the compensator. The device comprises transformation means (3, 4, 11, 12, 13) which represents the sensed voltage as a voltage vector (Vdq) in a rotating two-phase system of coordinates and form a compensation signal (Sc) in dependence on a sensed change of the angular position of the voltage vector in the two-phase system of coordinates. The device further comprises summation means (9) for forming the reference value for reactive power flow through the compensator in dependence on the compensation signal.

Abstract: A method for detecting compressor or system degradation or malfunction in a multiple circuit compressor system includes the steps of providing a multiple circuit compressor system including at least a first circuit and a second circuit; and comparing a first value corresponding to an operating parameter of the first circuit with a second value corresponding to an operating parameter of the second circuit.

Abstract: A compressor is provided with a fluid tight electrical connector. The electrical connector is sealed against the sealed compressor housing, and a cable is attached to a connector housing. Since the cable is separately attached to the connector housing, it is not directly connected to terminal pins in the compressor. This reduces damage to those terminal pins. Further, unique sealing arrangements make the electrical connection fluid tight.

Abstract: A refrigerating compressor control circuit installed in a refrigerator and connected between AC power supply and the compressor motor of the refrigerator and adapted for controlling the operation of the compressor motor, the refrigerating compressor control circuit including a CPU (central processing unit), a current phase detector, a voltage phase detector, a trigger circuit having a TRIAC, a voltage level detector, a high current detector, a low current detector, an input filter, and an output filter. The CPU starts the compressor motor a length of time delay after a sudden shutdown, preventing damage to the compressor motor due to high pressure of cooling agent, and controls the output voltage value subject to the status of the load at the compressor motor.

Abstract: A refrigerating compressor control circuit installed in a refrigerator and connected between AC power supply and the compressor motor of the refrigerator and adapted for controlling the operation of the compressor motor, the refrigerating compressor control circuit including a CPU (central processing unit), a current phase detector, a voltage phase detector, a trigger circuit having a TRIAC, a voltage level detector, a high current detector, a low current detector, an input filter, and an output filter. The CPU starts the compressor motor a length of time delay after a sudden shutdown, preventing damage to the compressor motor due to high pressure of cooling agent, and controls the output voltage value subject to the status of the load at the compressor motor.

Abstract: A protective device (3) for a hermetic type electromotively driven compressor (1a) includes a protector assembly (30) having a housing (32) with an electric current fuse (34) which detects a predetermined over-current. The housing (32) comprises an electrically insulating skirt member (31) formed so as to block a conductive part on the side facing an external connection terminal. By forming the electrically insulating skirt member (31) of housing (32) for a hermetic type electromotively driven compressor, insulation distance between a conductive part such as the electric current fuse (34) and an external conductive part such as a metal wall part (21) is set to be 9.5 mm or more.

Abstract: A compressor assembly comprises a compressor, a motor protector, and a signaling device. Upon an overload condition, the motor protector activates. The signaling device also activates to serve as an alert that the compressor is not malfunctioning but instead is in an overload condition.

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 starting device for compressors has a PTC resistor and a protection device, both of which are inserted in a casing fitted with couplings for connection to the standard coupling pins present on compressors. A start capacitor or a run capacitor is also included in the casing. The device has a box-shaped casing with teeth or the like which is designed to snap onto the compressor structure, which box-shaped casing contains a thermal protection device, a starting device, in particular constituted by a PTC resistor, and a capacitor which may be a start capacitor or a run capacitor, as the case may be. The casing is fitted with a connector for connection to the pins of the standard connectors on compressors so that the assembly can be fitted simply by connecting the device to the compressor connector, the casing being snap-fitted into its seating in such a way as to eliminate the risk of its becoming disconnected even as a result of vibrations transmitted by the compressor motor.

Abstract: An improvement in a starting system for an electric motor, which drives a hermetic compressor of refrigeration and comprises a main winding (1), and an auxiliary winding (2), which are energized by an electric current source (3), through a hermetic terminal (40) affixed to the outside of the compressor shell, the auxiliary winding (2) having a terminal connected to the electric current source (3) through a starting device (10) mounted inside the compressor shell and in series with a fusible element (20) to be opened when submitted to an electric current, in order to definitively interrupt the energization of the auxiliary winding (2) by means of the starting device (10), said hermetic terminal (40) being designed to receive an external starting device (50), in order to promote the selective connection between said other terminal of the auxiliary winding (2) and the electric current source (3) upon the definitive opening of the circuit defined by the fusible element (20) and the starting device (10).

Abstract: A device for control of an electric motor-driven compressor of an air-conditioning circuit has a control circuit and an inverter for applying a variable frequency to the electric motor for motor speed control. The control circuit includes a potentiometer and a controlled switch and enables a normal-operation mode under the control of the potentiometer as well as a degraded-operation mode in which the speed of the electric motor is a minimum, and a safety mode in which the operation of the electric motor is prevented.

Abstract: A two stage reciprocating compressor and associated HVAC systems and methods are disclosed. The reciprocating compressor includes a crankshaft having an eccentric crankpin, a reversible motor for rotating the crankshaft in a forward and a reverse direction, and an eccentric, two position cam rotatably mounted over the crankpin. The crankshaft and cam combine to cause the piston to have a first stroke when the motor operates in the forward direction and a second stroke when the motor operates in the reverse direction. The cam and crankpin also include stabilization means to restrict the relative rotation of the cam about the crankpin. A lubrication system is provided to lubricate the engaging surfaces of the crankshaft and cam and between the cam and the bearing surface of the connecting rod. There is also provided a control for selectively operating the motor either in the forward direction at a first power load or in the reverse direction at a reduced second power load.

Abstract: An assembly of starting elements and protectors for use with electric motors. One of the objectives is to provide an assembly which can be quickly and easily adapted to the housing of a compressor. This objective is achieved by the assembly comprising a capsule having a base (1) and a cover (2) that can be fitted onto the base, a PTC element (80) disposed in the capsule and a motor protector (9) that can be fitted into the capsule in the fitted position of the cover onto the base, the capsule can be received on pins of a terminal connector of a convention compressor.

Abstract: A terminal connector (10, 60, 80, 100, 120, 142) for connecting a lead wire to a terminal which is a component of a current path so that the current path will be established. The terminal connector has a lead wire attachment portion (12, 62, 82, 102, 122, 144) which is fixed to the terminal connector with continuity maintained with respect to the lead wire, a terminal mounting portion (13, 63, 83, 103, 123, 143) mounted on the terminal, a fuse portion (14, 64, 84, 104, 124, 145) which electrically connects the lead wire fixing portion and the terminal mounting portion to each other and which melts at a predetermined overcurrent, and a reinforcement portion (15, 85, 105, 125, 146) which protects the fuse portion against external forces.

Abstract: A compressor control device for a refrigerator and a method thereof sense a momentary power failure by comparing a set revolutions per minute with an operation revolutions per minute, and control an on/off operation of the compressor according to a compressor driving state after a power comeback or during a power failure duration when occurring a momentary power failure, thereby protecting the compressor. The compressor control device includes: a revolutions per minute sensor for sensing an operation revolutions per minute of the compressor; and a controller which determines a momentary power failure by comparing the operation revolutions per minute sensed by the revolutions per minute sensor with a set revolutions per minute, and controls an on/off operation of the compressor according to a compressor driving state after a power comeback or during a power failure duration when occurring a momentary power failure.

Abstract: This invention provides a power conversion apparatus capable of improving the power factor of the power supply and making the harmonic component of the power supply match or very closer to the IEC standard, and an air conditioner using the same.

Abstract: When an air-conditioning is started, a determination is made as to whether a power relay is run so as to keep a compressor in a power-on state. When the power relay is in the power-on state, the running current of the power relay is detected. At this point, if the current value does not reach to a predetermined value, it is determined that the compressor is stopped in an exterior unit for protection.

Abstract: A hermetic electric compressor includes a motor unit having a stator coil and a compressor unit driven by the motor unit for compressing refrigerant gas. A temperature sensor is provided at the stator coil for monitoring a temperature of the stator coil. A control unit is further provided to control a rotational frequency or speed of the motor unit via the stator coil depending on the monitored temperature of the stator coil. The temperature sensor and the control unit are connected via a shielded cable or a twisted pair. The shielded cable or the twisted pair may be grounded via a capacitor. Further, a thermostat may also be provided at the stator coil and connected in series to the temperature sensor.

Abstract: A compressor protective device for a refrigerator including a voltage sensor detecting a voltage applied to a compressor through a shunt resistor; a voltage amplifier amplifying a voltage signal from the voltage sensor; a voltage converter converting the voltage signal, amplified by the voltage amplifier, into a voltage of absolute value; and a controller producing a high signal or low signal in response to the voltage signal out of the voltage converter to control a turn-on or turn-off operation of the compressor, a method of protecting a compressor for a refrigerator having a voltage sensor and a controller, including the steps of determining whether or not the compressor is turned on and an error flag is set; it the error flag is set, determining whether or not an output voltage of the voltage sensor is higher than a reference voltage; if the voltage of the voltage sensor is higher than the reference voltage, determining that an overvoltage is applied to the compressor, and increasing error data in the con

Abstract: A short prevention control apparatus of an air conditioner for electric vehicles comprises a circuit breaker for a high voltage power source used to drive a compressor of the air conditioner, a drive circuit for driving a compressor motor and a short detecting circuit connected between a coupling wire and ground, wherein the wire connects the circuit breaker and the drive circuit. The short detecting circuit detects a short at a position between ground and a polar bus terminal of the drive circuit or an internal terminal of the compressor motor, when supply of a high voltage direct current is interrupted by the circuit breaker. A short in the air compressor side may be detected and determined without affecting the running of the electric vehicle.

Abstract: A sensor is provided for monitoring temperatures within a discharge tube on a scroll compressor. If the temperature is too high, this is an indication of the loss of charge situation. When the temperature on the discharge tube exceeds the temperature indicative of a loss of charge, then the motor is stopped. In one embodiment, a heat fusible link melts when the temperature is exceeded and sends a signal to a control to stop the motor. A repair person must then visit the compressor and repair the compressor before it can be restarted. In this way, the system provides a very inexpensive control for eliminating operation of the compressor and its associated refrigeration system in a loss of charge situation.

Abstract: The present invention is a compressor plug with internal thermal overload protection. It simplifies and improves the installataion of, and means of conducting electricity to, a compressor such as is used as a refrigeration compressor. It comprises a housing which contains electrical connections that are molded integral to the housing. The housing further comprises a clearance that accepts a thermal overload protection device. The housing further comprises an insert that serves as a structural member reinforcing said housing. The insert can include a slot which permits mounting of said compressor plug to a top of a shell used to house a refrigeration compressor.

Abstract: Motor protection for air conditioning and refrigeration compressors includes in a first embodiment a cluster block (22) having a seat for a hermetic motor protector (24, 24') and mounting a combination terminal/fusible link (26/26d, 26d') in which the motor protector and combination terminal/fusible link can be exposed to cooling fluid contained in the compressor container and the cluster block is mounted on a lead-through pin (18a) of a header (18) in the container wall. In a second embodiment the cluster block (30) is mounted on all three pins (18a, 18b, 18c) of header (18) with pin connectors received in parallel extending channels (30a, 30b, 30c) of the cluster block. In another embodiment the cluster block (40) is irregular in configuration in order to accommodate available space in certain compressor containers and has a lid (40g) to enclose the motor protector.

Abstract: Problems in shutting down the compressor in a vapor compression air conditioner in response to high pressure, low pressure and frozen refrigerant conditions are eliminated in a protection circuit that includes a contactor coil to control the power supply to the compressor. The use of a semiconductor switching configuration in the protection circuit provides for disconnecting the power to the compressor under fault conditions and for ensuring that the power connection to the compressor remains disabled until the conditions which initially triggered the protection circuit are corrected.

Abstract: A comparison voltage which is stepwise changed by control of a microcomputer through photocouplers is compared with a voltage of a direct-current power supply, and a signal of comparison result is given to the microcomputer through a photocoupler. The voltage of the direct-current power supply is detected on the basis of the comparison voltage when the signal of the comparison result changes.

Abstract: The present invention involves control and protection circuit for a compressor motor which includes an inductively activated contactor for controlling the flow of current to the compressor motor. The circuitry of the present invention includes a plurality of current detectors associated with each phase winding of the compressor motor for sensing the current in each phase winding. The sensed currents are combined in a predetermined manner and used to provide protection against an overcurrent condition, single phase operation and light loading condition. Additional detector circuits are also connected to the present control and protection circuit to provide protection against high temperature in the compressor motor windings, high temperature in various component of the compressor motor, and undervoltage in the power supply.

Abstract: A thermal protector for a hermetic electrically-driven compressor includes a thermal switch and a cluster socket. The protector is mounted inside a compressor housing on a terminal assembly mounted in a wall of the compressor housing. A casing of the thermal switch and a header plate hermetically closing an open end of the casing integrally form a flange on the peripheral edges when the header plate is secured to the casing. The thermal switch has two terminals one of which is provided with a receptacle into which one of terminal pins of the terminal assembly is fitted, and the other terminal is connected to a common lead wire of a compressor motor. The cluster socket has a plurality of terminal cavities for connecting windings of the motor to the terminal assembly. A body of the socket has a face having a pair of holding portions for holding the flange. Each holding portion has a hook-shaped portion at an end.

Abstract: A minimum off-time device according to the present invention that delays the restart of a compressor motor of a refrigeration system after power provided to the motor has been interrupted. The minimum off-time device is a standalone unit that is located outside the refrigeration system. The device is retrofitted to the refrigeration system by simply plugging the power line of the system into the device, which is then plugged into an AC wall receptacle, or alternatively, the device can be connected between the power line of the refrigeration system and an electrical circuit breaker panel. The minimum off-time device normally allows power from the AC power source to reach the refrigeration system. However, when a power interruption occurs at the AC power source, and subsequently, power is reapplied, the minimum off-time delay device immediately disconnects the refrigeration system from the AC power source and begins a timing sequence.

Abstract: A thermal protector for a hermetic electrically-driven compressor including a hermetically sealed housing in which a power-supply terminal, an electric motor and a compressor are enclosed with a predetermined amount of refrigerant gas is disclosed. The thermal protector includes a thermally responsive switch having first and second lead terminal pins for securing first and second connecting terminals respectively and a holder formed from an electrically insulating material and including first, second and third cavities. Each of the first and second cavities has an opening in its one side. The first cavity accommodates the thermally responsive switch while the second cavity accommodates a secured portion between the lead terminal and the connecting terminal with a hardenable electrically insulating filler filling up the second cavity. Alternatively, the second connecting terminal is secured to a wall of the holder by an insert molding so as to extend through the wall, instead of use of the filler.

Abstract: In air conditioner having a power-variable compressor, an inverter for varying the driving frequency of the compressor through V/f control, a controller for supplying a variable-frequency control instruction in accordance with the air conditioning load to the inverter, and an input voltage detector for detecting a source voltage input to the inverter, the controller includes reference means for beforehand storing V/f value data corresponding to plural voltage sections to which a predetermined range of the input voltage to the inverter is divided at a predetermined voltage interval, and selects data representing the ratio (V/f) of the output voltage (V) corresponding to the detected input voltage and the driving frequency (f) from the reference means to output the variable frequency control instruction to the inverter so that an air conditioning operation is carried out in accordance with the air conditioning load.

Abstract: A system which drives a compressor of a refrigeration system at one or more speeds. The system includes a motor having a stationary assembly and a rotatable assembly. The stationary assembly includes windings adapted to be commutated in at least one preselected sequence. The rotatable assembly is in magnetic coupling relation to the stationary assembly and in driving relation to the compressor. The motor drives the compressor at a desired speed corresponding to a speed select signal representative of one of the speeds. The system further includes an application specific integrated circuit (ASIC) connected to the motor. The ASIC receives the speed select signal and is responsive to it for generating a commutation reference signal. The commutation reference signal in combination with the commutation signal generates a peak current demand signal and thereby cause the motor to operate at the desired speed.

Abstract: Control circuit for a refrigerating system, used in hermetic compressors, comprising first and second temperature sensors (61,62) and a current sensor (63) for the current drawn by the motor, said control circuit including a central processing unit (30), which instructs at least the selective closing of first and second driving switches (40,50), which are respectively connected with a main winding (11) and with a starting winding (12) of an electric motor (10), when the first temperature sensor (61) detects a temperature inside the refrigerating cabinet corresponding to a maximum value of an ideal temperature interval, previously informed to the central processing unit (30), the temperature of the motor (10) and the current drawn by said motor (10) being within their respective ideal operative values, previously informed to said central processing unit (30).

Abstract: The present invention involves an inductively activated silicon switch for a control and protection circuit for motors and compressors. The circuit includes a logic gate for combining both motor control and protection functions. The logic gate has inputs from a thermostat, a compressor shell temperature circuit, a fan overheat detection circuit, a motor start relay circuit, and motor load sensing circuits. The logic gate output is connected to an oscillator for inductively activating the power output stage, as well as a start relay, a compressor shell temperature hysteresis circuit, and a fan timer circuit connected to the fan control circuit. The control circuitry further includes an over-ride circuit for manually allowing a limited number of immediate restart attempts.

Abstract: A delay-on-break circuit adaptable for A.C. or D.C. applications utilizes a timer and a pair of comparators to prevent a load from being re-energized until at least a predetermined period of time has elapsed since the most recent deenergization of the load. A feedback element, such as a zener diode, connected between the output of one of the comparators and a feedback input thereof provides reliable latching of the load through zero crossings of the line in A.C. applications without use of a latching capacitor while simultaneously providing brownout protection capable of rapidly deenergizing the load in the event of an undesired decrease in line voltage.