Abstract: A drive force distribution control apparatus in which if a relay output voltage (Vah) detected by relay-output-voltage detecting means (30) is lower than a first threshold, the relay is repeatedly and successively turned on and off multiple times, and then if the relay output voltage (Vah) detected later by the relay-output-voltage detecting means (30) while an engine speed (Er) is higher than a second threshold and an ignition switch (IG) is on is still lower than the first threshold, it is determined that there is an abnormality that keeps the relay stuck open, and then control for switching the drive mode from a four-wheel-drive mode to a two-wheel-drive mode is executed.

Abstract: When an electricity storage unit is being charged or discharged, a control circuit obtains efficiency Efn of a DC/DC converter based on input/output voltage value Vi, input/output current value I and electricity storage unit voltage value Vc detected by an input/output voltage detection circuit, an input/output current detection circuit, and an electricity storage unit voltage detection circuit, respectively. By using temperature T a detected by temperature sensor, when efficiency Efn lies out of predetermined range (from Emin to Emax) according to input/output voltage value Vi, input/output current value I, electricity storage unit voltage value Vc and temperature T, at least any one of an electricity storage unit and the DC/DC converter is determined to be abnormal.

Abstract: An auxiliary power system for an electrical load in a vehicle electrical system includes an auxiliary battery, a thermal transducer in physical contact with the auxiliary battery, a charger circuit for controlling the charging of the battery in response to at least a temperature of the auxiliary battery, and an output power delivery circuit for providing power to an electrical load during normal and emergency conditions. The auxiliary power system is housed in a thermally-conductive enclosure that is in thermal communication with the charger circuit and the power delivered circuit. The power delivery circuit selectively delivers power to the electrical output from both an electrical input terminal and from the battery based on the magnitude of a voltage available on the electrical input terminal.

Abstract: Equipment for vehicle in accordance with the present invention includes: a vehicle-mounted unit which runs with respect to a vehicle body ground on a side of a negative electrode of a battery; an impedance component having an end connected to the vehicle body ground, and another end connected to a circuit ground; a circuit to be controlled which runs with respect to the circuit ground; a control unit which runs with respect to the circuit ground, for controlling the circuit to be controlled and for outputting a communication signal in a digital form which is to be transmitted to the vehicle-mounted unit; and a communication interface circuit which runs with respect to both the vehicle body ground and the circuit ground, for cancelling a potential difference between the vehicle body ground and the circuit ground, and for carrying out bidirectional communications between the vehicle-mounted unit and the control unit.

Abstract: In a steering control unit, a U-phase feed line branches into paired branch feed lines, phase-open MOSFETs are provided in middle portions of the branch feed lines, phase-open MOSFETs are provided in middle portions of a V-phase feed line and a W-phase feed line, and the phase-open MOSFETs are arranged in such a manner that parasitic diodes are in the same orientation with respect to a motor. When an abnormality occurs, all the phase-open MOSFETs are turned off. Then, a closed circuit, which includes phase coils and through which electric currents flow, is no longer present.

Abstract: Methods and systems are provided for detecting loss of isolation of a motor, connections, or phase cables while an AC motor is operating. The system includes a power supply that is substantially isolated from the ground or chassis having a power supply voltage, and a power inverter electrically coupled to the power supply. The power inverter is configured to provide AC current from the power supply in an AC phase at an AC terminal, with the phase having current at a fundamental frequency that controls the motor speed. An electric motor is electrically coupled to the AC terminal of the power inverter and has a chassis that is substantially electrically isolated from the AC terminal of the power inverter under normal operating conditions. A processor is configured to control the AC current provided by the power inverter. The processor is configured to receive a first voltage signal related to current flowing through a motor chassis.

Abstract: In a motor control device that drives a plurality of motors with one DC power supply, detection of a short circuit fault occurring in the motors is realized with an inexpensive configuration. In order to drive the plurality of motors (105, 106), a current detection resistor (404, 405) is arranged between a connection point on positive terminal sides of a plurality of electric power converters (401, 402) connected in parallel to a DC power supply (403) and a positive terminal of the DC power supply, or also between a connection point on negative terminal sides of the plurality of electric power converters and a negative terminal (ground) of the DC power supply, to thereby detect the short circuit fault based on a voltage of the current detection resistor.

Abstract: A first semiconductor switching element connects to a high side of a motor and includes a diode whose cathode faces the high side. A second semiconductor switching element having a diode resides on a low side of the first semiconductor switching element. A third semiconductor switching element having a diode resides on a low side of the motor. A fourth semiconductor switching element is connected in parallel to the motor and configures a return current circuit that includes a return current element and causes a return current that arises when the first semiconductor switching element turns off to flow through the return current element. A control portion controls on-off states of the first to the fourth semiconductor switching elements and performs return current circuit failure detection based on a first monitor voltage that is an electric potential of a connecting point between the first semiconductor switching element and the motor.

Abstract: High-power synchronous motors are commonly used in mining operations, for example, in gearless draglines, gearless conveyor drives, and gearless mill drives. Substantial electromagnetic energy is stored in the inductive field windings. In the event of a system fault, such as a short in the direct current power source exciting the field windings, the electromagnetic energy needs to be discharged from the field windings. This electromagnetic energy is typically dissipated as waste heat through a resistor. Disclosed is a field discharge system in which the electromagnetic energy is captured and stored as electrical energy in a capacitor. If an ultracapacitor bank is used for storage, the charged ultracapacitor bank can be used as a backup or auxiliary power source for mining operations. The discharge time is sufficiently small that high speed circuit breakers are not needed to disconnect stator windings from the alternating current power source when a fault occurs.

Abstract: A method comprises determining whether a ground fault on a bus (110) operative to drive the system (100) exceeds a first threshold level, (502) receiving values of phase currents of a first motor, (504) calculating a sum of the values of the phase currents of the first motor (106) responsive to determining that the ground fault on the bus exceeds the first threshold value, and (504) determining whether the sum of the values of the phase currents of the first motor (106) exceeds a second threshold value (506).

Abstract: A motor control center communication system configured to interface with a communication network. The system includes a plurality of motor control units (MCUs), and a MCU controller configured to transmit and receive data signals via the communication network to and from, the plurality of MCUs. Each of the plurality of MCUs includes a magnetic contactor having electrical contacts operable between open and closed positions, and a local control module operatively connected to the associated magnetic contactor and to the MCU controller, and configured to monitor a status of the electrical contacts, transmit the monitored status information to the MCU controller, and actuate the associated magnetic contactor based on data signals received from the MCU controller.

Abstract: A method and a circuit are provided for the commutation of brushless direct-current motors (BLDC motors), without using sensors, and especially to a method and a circuit for producing rotor position signals, without using sensors, for the commutation of brushless direct-current motors. In the method and the circuit Hall sensor signals are emulated without sensors and rotor position signals free of disturbing pulses and with a correct phase position are generated from said signals. The rotor position signals can be used to carry out a reliable, sensor-free commutation.

Abstract: A power limiting system for multiple electric motors includes an electrical power generating component, such as an alternator, and a plurality of motor controllers connected to an electrical bus. Each motor controller compares the voltage on the bus to a specified minimum voltage and a specified maximum voltage, and reduces its electric power output if the voltage on the bus is less than the maximum voltage while continuing to operate the electric motors.

Abstract: A drive system for a multi-phase electric machine with a permanent magnet rotor, the drive system may comprise conduction paths for each phase. Detectors on each of the conduction paths may determine electrical condition of the conduction path. At least one selectable interconnection path may be present between all of the conduction paths and at least one selectable interconnection path may be operable to connect all of the conduction paths together responsively to at least one of the detectors determining that the electrical condition of its respective electrical path is representative of a predetermined electrical fault condition so that heating of the rotor during continued rotation of the rotor is prevented.

Abstract: A motor control circuit (MC) comprising input terminals (IT1, IT2) to receive a rectified input voltage (Vrm), and output terminals (OT1, OT2) to supply a motor drive signal (Vm). A switching circuit (1) is alternately in an on-state (Ton) and an off-state (Toff) for intermittently coupling the input terminals (IT1, IT2) to the output terminals (OT1, OT2). A controller (2) controls the switching circuit (1) to be (i) in the on-state (Ton) during a first period in time (T1) when an amount of magnetic saturation of the motor is smaller than a predetermined value, and (ii) alternately in the on-state (Ton) and the off-state (Toff) to obtain a pulse width control of the motor drive signal (Vm) during a second period in time (T2) when the amount of magnetic saturation of the motor is larger than the predetermined value.

Abstract: A method for operating an electric machine with a driver system is provided, in which an operating variable of the electric machine and/or of the driver system is monitored. The validity of the input variables is checked with regard to their checksum and whether the input variables are up-to-date, and the permissibility of an actual moment (Mist2) of the electric machine depending on the operating state of the electric machine is checked. In case of invalid input variables or invalidity of the actual moment (Mist2), a fault reaction is initiated. In addition, the implementability of the planned change of rotary speed is checked and, in case of non-implementability, changed over into a more favorable mode of operation of the electric machine. An electric machine used as a starter/generator in a motor vehicle can be monitored.

Abstract: A driving device includes a motor, a first rotating portion, a second rotating portion, a piezoelectric assembly, and a controlling unit. The motor includes a rotating shaft. The first rotating portion is fixed to the rotating shaft. The second rotating portion is engaged with the first rotating portion. The piezoelectric assembly is sandwiched between the first rotating portion and the second rotating portion. The controlling unit is electrically connected to the motor and the piezoelectric assembly. The controlling unit is configured for storing a predetermined voltage, and determining whether an electric voltage output by the piezoelectric assembly is greater than or equal to the predetermined voltage and inactivating the motor if the electric voltage output by the piezoelectric assembly is greater than or equal to the predetermined voltage. A protection method for the driving device is also provided.

Abstract: A motor controller is provided. The motor controller includes a motor drive unit that drives a plurality of motors; a thermal shutdown unit that is provided in the motor drive unit and that stops the plurality of motors in the case of an overload; a lock signal generation unit that generates a lock signal corresponding to a respective one of the plurality of motors when a rotational speed of the respective motor reaches a threshold speed set for the respective motor; and an operation determination unit which, when the lock signal generation unit interrupts lock signals for all of the plurality of motors, determines that thermal shutdown unit has operated.

Abstract: An electric power source for a motor vehicle is equipped with a welded state discriminator, and while a positive-side contactor and negative-side contactor are controlled to be switched off, the welded state discriminator detects a voltage of a positive-side contactor or negative-side contactor on its loading side with respect to a connecting point of a battery unit on a positive side and a battery unit on a negative side. Accordingly, when in a plus voltage where the detected voltage thus obtained is larger than a predetermined voltage, the positive-side contactor is judged to be in a welded state, and when in a minus voltage where the detected voltage is larger than the predetermined voltage, the negative-side contactor is judged to be in a welded state.

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 fire or smoke barrier 1 has a curtain 2 deployed from a motorized roller 3 mounted in a head box 4. Remote from the head box and connected to the motor via a cable 5 is a motor controller circuit 6. A short circuit protection circuit 9 is connected to the motor within the roller at the motor end of the cable 5. On the motor side of the circuit 9 is a retarder circuit 10 connected across the motor terminals. The short circuit circuit comprises a pair of relays 11, 12, arranged with their normally open contacts 111,121 arranged in parallel. A drive voltage one 11 of the relays has its winding 112 across the input lines 14 of the circuit and the emf one 12 of the relays has its winding 122 across the output lines 15 of the circuit. The input lines 14 are connected to the cable lines 51,52 and the output lines 15 are connected to the motor terminals 16, via the retarder 10.

Abstract: An inverter controller comprising an AC motor as a load. A rectifying circuit converts AC power from an AC power source into DC power. A smoothing capacitor smoothens a DC voltage from the rectifying circuit. An inverter circuit converts DC power supplied via the smoothing capacitor into a desired frequency. A current detection circuit detects a output current of the inverter circuit. A voltage detection circuit detects a terminal voltage (Vpn) of the smoothing capacitor. A voltage command calculation circuit calculates a voltage command to the AC motor. A speed command calculation circuit calculates a speed command to be used when it is determined that the AC power source is in a power failure state or when the terminal voltage (Vpn) reaches a certain value.

Abstract: A connection unit includes a first relay connected between a first electrode of a first battery and a first power feed line towards a vehicle load, a second relay connected between a second electrode of the first battery and a second power feed line towards the vehicle load, a third relay and a current limiting resistor connected in series between the second electrode of the first battery and the second power feed line, a fourth relay connected between an electrode of a second battery having a polarity identical to the polarity of the first electrode and the first power feed line towards the vehicle load, and a conductor line connecting an electrode of the second battery having a polarity identical to the polarity of the second electrode with the second electrode of the first battery. There can be provided a connection unit suppressed in the number of components, suitable for usage in a vehicle incorporating a plurality of power storage devices, and a vehicle incorporating the connection unit.

Abstract: An electronic starter device for an electric motor including a first terminal connected in use to a mains voltage source selectively activatable by means of control means to feed respective starter and run windings of the electric motor; switch means arranged in series between the voltage source and the starter winding to selectively feed the starter winding; generating means of a first low voltage potential (V1) directly connected to the feeding terminal; timer means including at least one capacitor and means for selectively charging the capacitor by means of at least one first resistor; first driving means for activating the switch means; and second driving means for activating the first driving means, the latter being arranged logically in a cascade with respect to the second driving means, which are activated by means of the timer means.

Abstract: An electric circuit for supplying power to a DC application is disclosed. The electric circuit comprises a DC power source (1) connectable to an alternator charging circuit (2), an FET (T7), and a capacitor (8) connected across the gate terminal and the source terminal of the FET (T7). The drain terminal of the FET (T7) is connected to a negative terminal of the DC source (1). The FET (T7) protects the circuit against accidental connection of the alternator charging circuit (2) to the DC power source (1) with reversed polarity, by opening a switch (6) of the FET (T7) when this occurs. The capacitor (8) protects the FET (T7) from being pushed into avalanche in case a load-dump transient occurs. This is because the capacitor (8) in this case will charge and discharge, thereby introducing a time delay before the switch (6) is opened. Protection against load-dump transients is thereby obtained by means of a small component with low energy dissipation.

Abstract: In a control system and a method for operating a permanent-magnet electrical machine, when the electrical machine is switched off after one of a functional computer and a monitoring computer of the control system has identified a fault, in order to reduce the braking torque of the electrical machine, which is switched-off but still rotating an output stage of the control system is subjected to a three-phase short circuit if the rotation speed D1 does not fall below a definable limit value GR1 or if a voltage U_DC of the output stage (2) exceeds a limit value Umax, and when the rotation speed D1 is below the definable limit value GR1 and a voltage U_DC of the output stage does not exceed a limit value Umax, all the circuits breakers (2o1, 2o2, 2o3, 2u1, 2u2, 2u3) of the output stage (2) are opened in order to fully disconnect the electrical machine from the output stage.

Abstract: Specific anomalies and details of failures as well as measures thereagainst are described that might possibly occur in electric power converters that drive and control permanent-magnet synchronous motors. An electric power converter capable of stable operation has a protective function of taking proper measures against such failures that might possibly occur.

Abstract: When an upper arm of U-phase has failed because of short-circuit, lower arms of V-phase and W-phase as the opposite arms are switching-operated. When only the lower arm of V-phase is turned on, a route of motor current passing through an IGBT element from a V-phase coil is formed, and therefore, the motor current returning to the short-circuited phase decreases. Further, by the switching operation of the arm opposite to the short-circuited arm, an AC current is induced in a motor generator. Therefore, it is possible to continuously drive the motor generator while preventing increase in the current passing through the short-circuited phase, without adding a new device structure. This ensures running of the vehicle in the limp mode.

Abstract: Power supply switching apparatus comprising an output switch for supplying power from a power supply to a load connected to an output terminal, a driver for controlling turn-on of said output switch, and a control signal generator for controlling said driver to produce a desired progressive turn-on characteristic. The apparatus also includes overload detection means responsive to a parameter of the load relative to a reference signal to provide a fault signal in case of detection of an overload condition after a turn-on phase of said output switch. The control signal generator is responsive to the reference signal to activate said overload detection means to provide a fault signal during the turn-on phase of the output switch even in presence of a severe overload condition at the output terminal.

Abstract: In a rotary electric system, a switch member includes at least one of a first switch and a second switch. The first switch is connected between a neutral point of multiphase stator windings and a high-side electrode of a direct current power source. The second switch is connected between the neutral point and a low-side electrode of the direct current power source. A controller works to turn the switch member off and on thereby switching control of the multiphase inverter between full-wave driving mode and half-wave driving mode. The full-wave driving mode allows the controller to drive all of the high-side and low-side switching elements per phase of the multiphase stator windings. The half-wave driving mode allows the controller to drive any one of the high-side switching element and the low-side switching element per phase of the multiphase stator windings.

Abstract: A surgical instrument includes an end effector having an actuation assembly to effect a surgical procedure when actuated. An electric motor has a rated operating voltage and is operationally connected to the end effector to operate the actuation assembly. A power supply is electrically connected to the motor and selectively powers the motor to actuate the actuation assembly at least 1 and less than 16 times during a clinical life of at least one of the end effector, the motor, or the power supply. The power supply has a battery cell with a critical current rate. When activated to power the motor and actuate the actuation assembly, the power supply operates the battery cell at a super-critical current rate during a non-zero super-critical pulse discharge period lasting less than approximately 16 seconds. The power supply operates the motor above the rated operating voltage during the super-critical pulse discharge period.

Abstract: The present invention relates to a method for determining the existence of an earth-fault on-the-fly and thereby protecting a motor controller having a high- and a low-side DC-link, and having high- and low-side switching elements, the high- and low-side switching elements being operatively connected to the high- and low-side DC-link buses, respectively, the method comprising the steps of generating a fault signal, generating at least one test vector in response to the fault signal by switching at least one of the switching elements on, and measuring, while the at least one switching element is on, the magnitude of a current flowing in that DC-link operatively connected to the conducting switching element in order to detect an earth-fault. The present invention further relates to additional methods for on-the-fly determination of earth-faults.

Abstract: A method of detecting an output phase loss (OPHL) for a motor drive detects an abnormal OPHL operation when at least one phase of a three-phase current is continually zero. Each phase of the three-phase current is acquired, sampled, filtered, and compared. Hence, a corresponding zero-current counter value is continually added, and a corresponding abnormal current value is set as logic 1 when a zero-phase current of the three-phase current is continually zero. Finally, an OPHL certified value is set as logic 1 to confirm that the motor driver is operated in the abnormal OPHL operation. Therefore, a direct-current and an alternating-current OPHL can be detected before and after the motor driver is operated, respectively.

Abstract: A method for applying power to an electronically commutated motor (ECM) is described. The method includes connecting an AC voltage source to an input of a rectification circuit, connecting a DC voltage source to an output of the rectification circuit, and electrically connecting the DC voltage source and rectification circuit output to operational components of the ECM. The DC voltage source is capable of providing a voltage equal to or greater than a rectified voltage originating from the AC voltage source, and the DC voltage source is connected in parallel with the output of the rectification circuit.

Abstract: A control apparatus for controlling a fuel pump includes: an electronic switch provided in a circuit for connecting a power supply to a motor for driving the fuel pump; a current detector which detects a current which flows through the motor; and a controller which controls the electronic switch in a first PWM mode of a first frequency and a first duty ratio in a normal operation; and change a PWM mode to control the electronic switch in a second PWM mode of a second frequency lower than the first frequency and a second duty ratio lower than the first duty ratio when the current flowing through the motor exceeds a threshold current value in the normal operation.

Abstract: A clamping circuit is included in a phased motor control circuit, particularly on an electrical connection connected to at least one electrostatic discharge cell and/or the driver control electronics of the phased motor control circuit. The clamping circuit triggers when a voltage that exceeds a clamping turn-on threshold occurs on the electrical connector, sourcing or sinking the discharge current so as to protect the electrostatic discharge cells and/or driver control electronics from destruction by said discharge current.

Abstract: A microcomputer compares a low voltage LV and a middle voltage MV to a predetermined voltage Vth set at a value in the vicinity of the grounded voltage (0 V) on the basis of detected phase voltages Vu, Vv and Vw, and thus, detects a break in a power supply line.

Abstract: A permanent magnet machine (PMM) has a kinetic portion electrically coupled to a power conversion portion. Motive power is provided to the kinetic portion by a torque applied to a motive shaft coupled to a prime mover, such as an aircraft engine or an automobile engine. A sensor is effective to detect a fault condition in the kinetic portion. When a fault is detected, the sensor applies a voltage to a winding within the kinetic portion generating an opposing directional counter torque to the motive shaft. A combination of the torque and counter torque exceeds a fracture yield strength of the motive shaft. The fault condition is then rendered safe while the prime mover may continue normal operation.

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: A device for measuring the loss factor and/or measuring the phase angle between a voltage and a current and/or recording a voltage decay and/or current decay and/or recording partial discharge processes and/or measuring the propagation time on test objects that are to be tested, includes a housing in which at least one measuring circuit is arranged for measuring and/or recording purposes. A terminal adapter (12) is provided on the housing (9) to connect the test object that is to be tested directly to the housing (9).

Abstract: A motor bypass is controlled by a digital signal processor (DSP) with embedded control software that allows fault detection and annunciation, serial communications between both a variable frequency drive (VFD) and a bypass controller and the bypass controller and a host computer. The use of the DSP and embedded control software further allows for contactor coil control to provide fault tolerant operation as well as fault condition detection and annunciation to the user.

Abstract: A signaling device for a safety circuit has an input part for receiving an external state variable, at least one switching element and a control part. The control part controls the at least one switching element as a function of the external state variable, such that a signal applied to the input is communicated to the output. According to one aspect of the invention, the input of the switching element is internally connected to a fixed potential, preferably a fixed High potential. In a safety circuit for turning off a hazardous installation, such signaling devices are connected in series with one another to a safety controller. In such an arrangement, the control part of the downstream second signaling device also controls its switching elements as a function of the output of the first signaling device.

Abstract: A multi-phase AC motor driving device in which occurrence of failure is not erroneously determined is provided. In a multi-phase AC motor driving device including an inverter circuit; current detecting resistances Ru, Rv, and Rw, respectively arranged on lower arm of the respective phase of the inverter circuit, for detecting phase current of the motor; and a control portion and a PWM circuit for controlling ON/OFF operation of switching devices of the inverter circuit, the determination on the occurrence of failure based on the current values detected by the current detecting resistances is not made if the ON-duty ratios of the switching devices on the upper arms of the inverter circuit are not smaller than a predetermined value.

Abstract: Techniques include sensing electric signals from an actuator during a document stacking operation and determining whether an abnormal event has occurred based on the sensed signals. The techniques may find particular applicability, for example, to document acceptors that include piston-type stackers driven by a direct current motor.

Abstract: A pulse width modulator generates a PWM signal whose duty ratio is feedback-controlled so that a detection voltage according to a current across a secondary coil of a transformer is brought close to a reference voltage. A logic control unit performs a switching control of the current across the primary coil of the transformer, based on the PWM signal outputted from the pulse width modulator. A first protection circuit detects a circuit failure of an inverter and stops the switching control of the inverter when the circuit failure continues for a predetermined duration of error detection time. A second protection circuit monitors a feedback voltage corresponding to an output voltage of the inverter, and lowers the reference voltage sets the duration of error detection time short when the feedback voltage is lower than a predetermined threshold voltage.

Abstract: The present invention refers to an electric overload protecting device (100) capable of avoid overheating of motors (400) of refrigeration equipment, and further providing an additional protection at the end of its lifetime. Such additional protection is provided by means of a backup protecting element (300) comprising at least a first connection means (301) associable to an electric energy feeding source (600); a second connection means (302) associable to the motor (400); and a fusing linkage (303) directly connecting the first connection means (301) to the second connection means (302). Such fusing linkage (303) is capable of interrupting an electric current that runs through the motor (400). The first connection means (301), the second connection means (302) and the fusing linkage (303) are fully associated to each other in a single part. The present invention refers also to a motor start device (500) comprising the above mentioned overload protecting device (100).

Abstract: A motor sensing circuit with transient voltage suppression includes a sensing unit and an impulse absorber. The sensing unit has an electrical switch generating a pulse sensing signal when switching and a signal output terminal electrically connecting to the electrical switch and outputting said pulse sensing signal. The impulse absorber has a first terminal connecting to the signal output terminal of the sensing unit and a second terminal being grounded. Consequently, the impulse absorber is able to provide a route for a transient current to be drained away, with the transient current being generated by an impulse inputted the motor sensing circuit through the signal output terminal.

Abstract: A control portion instructs supply of an offset voltage while a disk remains stopped at the time of start. While the disk remains stopped at the time of start, a differential operational amplifier detects a voltage difference between a first voltage supply line and a second voltage supply line. When the absolute value of the voltage difference output by the differential operational amplifier is equal to or lower than a prescribed threshold value, a failure determination portion determines that a spindle motor has shorted out.

Abstract: When manufacturing a starting device for a three-phase electric motor, especially a soft starter, in at least one embodiment an arc quenching system is at least partly removed from a commercially available contactor that so becomes to a modified contactor. In at least one embodiment, a modified contactor is used as a contactor in the starting device.

Abstract: A circuit that electrically controls power includes at least one power control device and at least one heat extraction device. The at least one extraction device is in thermal contact with the at least one power control device. The heat extraction device is arranged such that it can be clamped to a fixed predefined electric potential and electrically insulated by the at least one power control device.