Abstract: An electric wire protection device includes a voltage adjuster that adjusts voltage on a power source side to be supplied to a load and a controller that includes a temperature calculation part which calculates temperature information of an electric wire based on a current value flowing through the voltage adjuster. The controller sets a first time constant as a time constant used to calculate the temperature information while the voltage adjuster is in the interrupted state, and sets a second time constant as a time constant used to calculate the temperature information while the voltage adjuster supplies power to the load. The first time constant is a value larger than the second time constant and equal to or larger than an actual time constant of the electric wire, and the second time constant is a value smaller than the actual time constant of the electric wire.

Abstract: The present invention provides a direct-current current transformer, or DCCT, yielding bandwidth from DC to several MHz. The DCCT according to this invention is a simple, open-loop, device in which flux densities occur at very low levels, avoiding difficulties occasioned by core saturation.

Abstract: A pump system. The pump system includes a pump, a motor coupled to the pump, a sensor coupled to a power source, and a controller. The motor operates the pump. The sensor detects an electrical characteristic of the power source. The controller executes a fault check, controls the motor, detects a change in the electrical characteristic, and suspends the execution of the fault check for a predetermined period of time when the detected change in the electrical characteristic is outside of a valid characteristic range.

Abstract: An area electric power system includes a number of direct current power sources, and a number of inverters operatively associated with the number of direct current power sources. Each of the number of inverters is structured to provide real power and controlled reactive power injection to detect islanding. An output is powered by the number of inverters. A number of electrical switching apparatus are structured to electrically connect the number of inverters to and electrically disconnect the number of inverters from a utility grid. A number of devices are structured to detect islanding with respect to the utility grid responsive to a number of changes of alternating current frequency or voltage of the output.

Abstract: A driving device includes a motor, a rotatable shaft rotated by the motor, a driven member, a magnetic material spring, and a power source. The driven member sleeves on an end of the rotatable shaft, and includes an end surface with at least one latching groove defined thereon. The magnetic material spring sleeves the rotatable shaft, and includes a first end fixed to the rotatable shaft and an opposite second end capable of inserting into the latching groove of the driven member. The power source includes two electrodes. The motor and the spring are electrically connected in series between the two electrodes of the power source.

Abstract: A modular control assembly is provided for on-machine control of a desired machine. One embodiment has a machine mountable base and a replaceable control unit, wherein the machine mountable base has a machine protection device. In various embodiments of the machine mountable base, the machine protection device may have a short-circuit protective device and a disconnect device. In addition, various embodiments of the replaceable control unit may have a variable frequency drive, a soft start device, or an adjustable overload protection device.

Abstract: A load control apparatus outputs a PWM signal to a switching element to control a load. The switching element is connected between a power supply and a grand in series with the load. An abnormal increase detecting unit outputs an abnormal increase detection signal when detecting abnormal increase in applied voltage, which is applied to the load, relative to target voltage. An abnormal decrease detecting unit outputs an abnormal decrease detection signal when detecting abnormal decrease in the applied voltage relative to the target voltage. An operating state monitoring unit outputs a normally operating signal when the load normally operates. A signal combining unit generates a combined signal by combining the abnormal increase detection signal, the abnormal decrease detection signal, and the normally operating signal and outputs the combined signal via a common signal output terminal.

Abstract: An inverter system having a semiconductor device, and a railway vehicle using this inverter, provide a more accurate determination of whether an abnormal heat generation from the inverter is associated with an error of the inverter system or is due to other causes, by use of a plurality of temperature detecting elements at a plurality of sites associated with the semiconductor device. An error detection section applies inputs from the temperature detecting elements, captures a trend of the differential value based on the plurality of temperature inputs using period sampling wherein an error associated with the semiconductor device, and not from some other condition such as outside environment temperature, is determined based on differences from, or a change in, the initial trend.

Abstract: In response to a system-off instruction, the drive system control technique of the invention controls individual motors of an electric cooling water pump and an electric cooling fan to stop (step S100), waits for elapse of a preset reference time period since start of the control of stopping the motors (step S110), and turns off a relay to disconnect a supply of electric power from a battery to a CPU of a control unit (step S120). Inactivation of the relay after elapse of the preset reference time period since start of the control of stopping the motor disconnects the supply of electric power to the control unit in the state of sufficiently low back emf generated by the motors. This arrangement effectively prevents malfunction of the control unit due to the back emf generated by the motors.

Abstract: A system, method, and device for protecting an induction motor are disclosed. The exemplary system may have a module for determining the current drawn by the motor and a module for determining the state of the motor. The system may calculate a used thermal capacity based on a first formula when the motor is in an active state. The system also calculates the used thermal capacity based on a second formula when the motor is in an inactive state. When the used thermal capacity attains a threshold, the relay is tripped thus removing current to the motor and preventing motor from overheating. A method to derive thermal time constants from desired trip time limits (such as those defined by IEC standards or the thermal limit curves provided by motor manufacturers) is also presented. For example, the thermal time constants can then be used in tacking motor used thermal capacity throughout various motor states.

Abstract: A thermal trip device in which a bimetal (2) is heated by overcurrent and performs trip operation of a circuit by curvature of the heated bimetal (2), wherein at least one part of the surface of the bimetal (2) is made to be black or matte black (7). Thereby, temperature of the bimetal (2) can be highly accurately measured using a no-contact thermometer. Furthermore, a temperature measurement part (8) of the bimetal is provided with a bending part (11), and the surface of the bending part is made to be matte black.

Abstract: A hermetic compressor is disclosed having an electric motor, a compressor unit, and an overload protector within a hermetically sealed housing. The overload protector includes a thermally activated switching device for selectively providing current to the electric motor, a heater element thermally coupled to the switching device, and a control circuit controlling the heater element. The overload protector allows the disconnection of power to the motor due to factors and conditions specified in the remotely located control circuit.

Abstract: A pair of spring mounted masses have sufficient inertia to remain stationary in response to a shock force applied to the housing of a trip assembly in a circuit breaker to block movement of the trip bar and thereby prevent a nuisance trip.

Abstract: A hermetic compressor is disclosed having an electric motor, a compressor unit, and an overload protector within a hermetically sealed housing. The overload protector includes a thermally activated switching device for selectively providing current to the electric motor, a heater element thermally coupled to the switching device, and a control circuit controlling the heater element. The overload protector allows the disconnection of power to the motor due to factors and conditions specified in the remotely located control circuit.

Abstract: An electric power supply device 13, combining an overload protector device 3 and a starter device 4 each other, and an equipment using thereof comprises a socket terminal 5 connected to an electric part of the overload protector device 3, and a convex portion 10c opposing to a tip opening portion 5a of the socket terminal 5, which is nearly in conformity with the shape of that tip opening portion and has a little gap therebetween, wherein while keeping superiority in work of assembling external apparatuses onto the terminal pins, prying force caused onto the tip opening portion when the socket terminals of the starter device are fitted onto terminal pins of an external equipment is suppressed, thereby to improve reliability.

Abstract: The invention eliminates light leakage in liquid crystal panel caused by burrs, i.e., protrusions, on a light waveguide plate causing misalignment when the light waveguide plate is seated in the main frame of a LCD module. The invention includes a a first frame located on the liquid crystal panel, and a second frame assembled with the first frame interposing the liquid crystal panel and the back light. The second frame has a recessed portion formed at a location corresponding to the protrusions of the light waveguide plate, wherein a distance from the fixed side wall of the light waveguide plate to the protrusions is sufficiently short so that dimensional variations between the protruding portion of the light waveguide plate and the recessed portion of the second frame are insignificant.

Abstract: The present invention provides an inter-layer structure between a power layer and a ground layer. The inter-layer structure comprises an insulative magnetic layered structure which comprises at least two insulative magnetic substances which are different in frequency characteristic of complex magnetic permeability.

Abstract: An electric power supply device 13, combining an overload protector device 3 and a starter device 4 each other, and an equipment using thereof comprises a socket terminal 5 connected to an electric part of the overload protector device 3, and a convex portion 10c opposing to a tip opening portion 5a of the socket terminal 5, which is nearly in conformity with the shape of that tip opening portion and has a little gap therebetween, wherein while keeping superiority in work of assembling external apparatuses onto the terminal pins, prying force caused onto the tip opening portion when the socket terminals of the starter device are fitted onto terminal pins of an external equipment is suppressed, thereby to improve reliability.

Abstract: Embodiments of a combination motor starting device and protector module including a motor start winding cut-out switch for an electric motor are described. In the one embodiment, the motor protector includes a heater element and a bimetallic protector switch, electrically connected in series and configured to be coupled between a power source and the motor windings. The bimetallic protector switch includes a stationary contact, a movable contact, and a bimetal element, responsive to current flow through the protector, controls movements of the movable contact. The heater element is positioned in heat transfer relationship with the protector bimetal element. The motor starting device, in one form, is a positive temperature coefficient resistor (PTCR) element configured to be connected in circuit with the motor start winding. A bimetallic cut-out switch is connected in series with the PTCR.

Abstract: A direct current (DC) electric motor is shifted between higher and lower operating speeds in response to motor operating conditions to prevent motor stalling, overheating and burnout. Switches are performed between two or among more than two operating curves defined for the DC motor with switches preferably taking place approximately at points of intersection of the operating curves. The high or higher speed curve typically results from inducing inefficiency into the motor such that continued operation along the high or higher speed curve can lead to motor stalling and even burnout. At or near the intersection points of motor operating curves, operation is switched from the high or higher speed operating curve to a lower speed, higher efficiency operating curve such that motor current is immediately reduced for the same motor speed and torque. If the motor is able to once again operate along the high or higher speed curve, a switch-back is made at or near the point of intersection.

Abstract: A temperature-sensitive switch (10) for protecting electrical parts against excess temperature and/or excess current comprises a bimetallic switching device (14) which opens or closes its contacts in response to an excess temperature. Said switching device (14) is contained in a casing (17) having a pot-like bottom part (18) and cover (19). A first heating resistor (15) is connected in circuit with the switching device (14) such that it locks the switching device (14) in a self-holding manner when said switching device (14) is actuated in response to an excess temperature. A second heating resistor (16) is connected in circuit with said switching device (14) and produces heat in response to a current flow therethrough. When an excess current flows through the second heating resistor (16) the switching device (14) is actuated. Both, the first and second heating resistors (15, 16) are integrated in said cover (19) of said casing (17).

Abstract: An overcurrent protection device for a motor M with an overheat prevention function having a housing 10 with fixed contacts 16, 18 and movable contacts 24, 26. A first snap acting bimetallic element 20 in the device is responsive to heat from overcurrent conditions and a second snap acting bimetallic element 40 is responsive to heat from the temperature for the motor M. The movable contacts 24, 26 are controlled by the first bimetallic element to cause engagement or nonengagement with the stationary contacts 16,18. Coupling members 42, 44 contained in the housing engage both bimetallic elements 20, 40 and allow the first overcurrent bimetallic element 20 to snap independently of the second bimetallic element 40 while providing for snap action of the second bimetallic element 40 to also cause the first bimetallic 20 to snap.

Abstract: A starting device for a single phase induction motor can reduce the power consumption and restart in a short time. The starting device for the single phase induction motor having a main winding and a starting winding comprises a starting positive temperature coefficient thermistor connected in series with the starting winding, a bidirectional current control device connected in series with the starting winding and the starting positive temperature coefficient thermistor, and an auxiliary positive characteristic thermistor having a heat capacity smaller than that of the starting positive temperature coefficient thermistor connected in parallel with the starting positive temperature coefficient thermistor, a terminal of the auxiliary positive temperature coefficient thermistor being connected to a gate of the bidirectional current control device.

Abstract: An overcurrent protection device 10 has a fixed 26 and a movable 32 contact electrically connected to a pair of terminals 14, 16 and a snap acting bimetallic member 34 which is responsive to a thermally resistive element 28, connected in series with the contacts between the terminals to cause the contacts to move from an engaged position to a disengaged position. The device further includes a current bypass path 24 adapted to be connected in parallel with the thermally resistive element 28 and a second thermally responsive bimetal member 24 b to cause the electrical connection. Additionally, a heater block 18 can be provided between the terminals 14, 16 which has a resistance significantly higher than that of the thermal resistive element 28.

Abstract: An air conditioner has a refrigeration system with a compressor, a motor for air-circulating fans, indoor and outdoor heat exchangers and a four-way valve connected through refrigerant conduits such that it can be operated selectably both for cooling and for heating. An electric heater is also provided for heating. An electrical circuit for the air conditioner has a series connection of (1) a first temperature switch which opens when the temperature of the motor becomes too high, (2) a thermostat of an ordinary kind which places its connector piece in an open or closed position by comparing room temperature with a user-set temperature level, (3) a relay which controls the switching of the compressor of the air conditioner on and off, and (4) a second temperature switch which opens when the temperature of the electric heater becomes too high.

Abstract: A method of assembling an overload protector for use in a combination starter-protector device adapted to be associated in circuit relation with a dynamoelectic machine. To practice this method, a conductive member is extended through a slot in a sidewall of a casing, and a contact section of the conductive member is located within an open ended recess in the casing defined by the sidewall and a base wall while a terminal section of the conductive member is located on an extension wall extending laterally of the sidewall. The terminal section is secured against displacement to the extension wall. A support for a bimetal switch element is disposed in an assembly position within the open ended recess, and the bimetal switch element is biased into engagement in circuit relation with the contact section.An overload protector, a combination starter-protector device and a method of assembling a starter-protector device are also disclosed.

Abstract: A motor protector and starter particularly suited for refrigeration compressor motors are mounted in the recess of a first housing portion with their resilient female sockets disposed in alignment with a pin receiving aperture. Leads are attached to terminals of the motor protector and starter components and directed through lead receiving apertures in the side wall of the first housing portion. A second housing portion is then snapped onto the first housing portion to provide a combination housing which can be installed on a compressor in a one-step on-line operation.

Abstract: A motor protector having a thermostat metal element thermally coupled to an electrical motor in a refrigerator compressor motor system has a heater responsive to motor current thermally coupled to the thermostat metal element and has an improved component arrangement to provide locked rotor and ultimate trip protection for the motor without requiring calibration of the operating temperature for the protector after assembly or after incorporation in the motor system.

Abstract: A motor protector having a thermostat metal element thermally coupled to an electrical motor in a refrigerator compressor motor system has a heater responsive to motor current thermally coupled to the thermostat metal element and has an improved component arrangement to provide locked rotor and ultimate trip protection for the motor without requiring calibration of the operating temperature for the protector after assembly or after incorporation in the motor system.

Abstract: The motor protection switch comprises a movable contact piece being manually movable by way of an actuator, which includes actuator buttons. The contact piece can be brought in and out of contact with a resting contact piece. The motor protection switch can also be released by overload current or short circuit current. A retracting or pullback mechanism with two settings settable from outside are provided for the actuator. In the first setting the pullback mechanism will hold the actuator in a trip position between the "on" and the "off" position after overload tripping or short circuit tripping has occurred. In the second setting the pullback mechanism will allow direct movement of the actuator from said "on" position into said "off" position after overload tripping or short circuit tripping has occurred.

Abstract: A door is provided having an automatic opening means for the door and a key locking facility for mechanically locking the door in a door closed position and electric circuit means connected with the motor means to sense a change in the electrical operating conditions of the motor above that which is normal for operation of the motor and to remove the above normal power thereby supplied to the motor in such circumstances.The sensing means preferably comprises a means which switches off the power once the electrical operating conditions are sensed above that which is normal and whereby it returns the power some time later and should the motor then reexperience electrical operating conditions above that which is normal the sensing means will again switch off the power to the motor.The sensing means desirably comprise a bimetallic cut out switch means.

Abstract: A combination starter-protector device for a winding circuit of a dynamoelectric motor comprises a housing structure having a perforated wall dividing the interior of the housing structure into starter and protector compartments. The starter compartment accommodates therein a positive temperature coefficient thermistor while the protector compartment accommodates therein a bimetal switch. The housing structure has two sets of terminals, one set of the terminals being adapted to be connected to the winding circuit of the motor whereas the other set of the terminals are adapted to be connected to a power source. The distance between the thermistor and the bimetal switch may be adjustable by the employment of a spacer element.

Abstract: A protective thermal relay comprises a main heater for heating a snap-action element of a bimetallic switch to open the switch. The main heater is connected in series with the motor or other device to be protected by the relay. There is also an auxiliary heater for the bimetal element that is energized through an abnormal condition detection relay, e.g., a negative phase sequence detector, when the abnormal condition occurs. The auxiliary heater is a positive temperature coefficient type and will heat and hold the switch in the motor off mode as long as the negative phase sequence or other abnormal situation remains.

Abstract: A thermoswitch is physically located on a portion of the current supply connector between the current source and the exciter winding of the starter motor. The portion, constructed as a simple strip with flaps holding the thermostat, influences the temperature-dependent control portion of the thermoswitch according to heating in the armature, field winding, and brushes of the starter motor. The thermoswitch turns OFF the starter system by interrupting current supply to the kick-in starter relay.

Abstract: Overload protection for a multispeed motor is provided in the form of a plurality of line break motor protectors positioned in good heat transfer relation with the motor windings and having heating elements in circuit with the motor windings to be responsive to excessive winding current and/or excessive winding temperature to disable the windings. Certain of the line break motor protectors are operational in more than one motor speed configuration. The line break motor protectors may be of the self-resetting temperature sensing variety and circuitry is included to insure that the motor does not restart until all protectors are reset subsequent to an overload condition.

Abstract: The invention is directed to a disconnect and overload bypass arrangement for a hand-held portable tool equipped with an electric motor supplied from a source of electrical energy and a manually operable on-off switch for switching the tool on and off. The arrangement includes a self-reclosing disconnect switch operatively connected to the motor to temporarily disconnect the same from the energy source in response to an overload condition; and, circuit control means for supplying energy to the motor at a reduced level when the disconnect switch is open whereby the motor will continue to operate at reduced torque pending self-reclosure of the disconnect switch and thereby provide the operator of the tool with an audible and visual indication that the motor has not been deactivated by manually actuating the on-off switch.

Abstract: A three phase motor is constructed with each of the three phase windings thereof split in half so that the motor may be selectively connected for energization from either a relatively high or relatively low source. Motor protectors are provided in the form of a three pole automatic resetting overload relay means and two thermostatic switches. The heaters for the individual poles of the overload relay means are connected in series with a half section of the individual phase windings and do not have to be changed when either high or low voltage energization is selected for the motor. The thermostatic switches are embedded in two of the other three winding sections but electrically insulated from the motor winding. The control contact means of the overload relay means and the thermostatic switches are connected in series with the energizing coil of the electromagnet for the contact through which the motor is connected to its energizing source.

Abstract: A fuse for a solid electrolyte capacitor is made of two exothermically alloyable metals such as aluminum and palladium. The fuse has a series electrical connection with and a thermal connection to the capacitor body. A defective and overheated capacitor section results in abnormally high currents so that the fuse temperature is elevated by ohmic self-heating and/or by the flow of heat from the overheated body. When the alloying temperature of the fuse is reached, the temperature of the alloying fuse momentarily becomes very high and opens essentially along its entire length.