Abstract: System for driving motors for operating switching units, in particular for an electrical supply substation, comprising control units for controlling the motors, wherein the control unit comprises, to have only one of the motors in operation at a time, a device for managing the priority of operation of the motors which is provided with a first line, referred to as the parallel line, carrying a binary datum comprising a first state representative of the stopping of all of the motors and a second state representative of the operation of any one of the motors, to which the units are connected in parallel, the parallel line being connected to a device for preventing/allowing the starting of the motor of each of the units and a second line, referred to as the series line, to which the units are connected in series in an upstream/downstream chain, the series line constituting a means for preventing the operation of the motors downstream of the any one of the motors on detection of a signal for starting the any one o

Abstract: In a display system, each of a plurality of sensor terminals estimates first information based on accumulated first measurement data and transmits the first information to a display device. The display device synchronizes a received plurality of kinds of the first information at time and classifies the plurality of kinds of first information into a plurality of first information groups, estimates, based on position information of the plurality of sensor terminals and the first information included in each of the first information groups, updates the first information group, generates, for each of the updated plurality of first information groups, based on map information including a region where a structure is located, image information including a distribution of values of the first information on a map, and displays an image based on the image information.

Abstract: A method for predicting a rotor temperature of an electric motor for an electric vehicle. The method includes measuring at least one of an operating parameter of the electric motor; inputting the at least one of the operating parameter of the electric motor into a predetermined regression model to predict a rotor temperature of the electric motor; and communicating the rotor temperature of the electric motor to a vehicle control module for managing the electric motor. The operating parameters includes a measured stator temperature, a torque level output, a rotor speed, and a coolant flowrate of the fixture electric motor. The electric motor may be that of an induction motor.

Abstract: A gear motor (motor device) comprising a three-phase motor and a terminal box housing a power supply connection terminal for connecting the three phase motor to an alternating current power supply, comprises: a power detection circuit that detects power to be supplied to the three-phase motor; a control unit that executes predetermined control if a load abnormality related to the three-phase motor or a driven device is detected based on power detected by the power detection circuit. The power detection circuit and the control unit are housed in the terminal box.

Abstract: A system and a method for diagnosing a contactor life using contactor coil current, whereby, after a current value of a current contactor coil is determined based on a resistance value and a voltage value according to a real-time temperature of a contactor coil, whether contactor lifetime has expired and an abnormal operation thus occurs can be previously diagnosed and predicted on the basis of whether an average current value when a corresponding contactor operates a preset number of times or more exceeds a threshold value.

Abstract: A portable ride-through (RT) tester provides a voltage drop at control circuitry of a motor starter to test its RT capabilities. The RT tester includes a variable transformer for manually controlling the magnitude of the voltage drop. Timing circuitry is programmed to count cycles of a 120 VAC input voltage to affect the occurrence and duration of the voltage drop. The primary windings of the transformer are connected to the 120 VAC. The variable secondary winding is connected to output terminals, which are electrically connected to the starter control circuitry via conductive probes. The power circuit of the starter is disengaged during testing. The timers sequentially provide the 120 VAC input voltage and the voltage drop at the starter control circuitry. Repeated testing at different durations and monitoring for tripping of relays/solenoids of the starter enables the tester to determine the exact ride-through capability of the motor starter.

Abstract: A motor drive controller comprises: a driver unit comprising semiconductor switches (SW1-SW4) for adjusting power supplied to a motor; a control unit for outputting, to the driver unit, a control signal (PWM1, PWM2) for controlling on and off of the semiconductor switches (SW1-SW4); and an overcurrent monitoring unit for monitoring for an overcurrent at multiple locations in the driver unit. The control unit outputs, to the driver unit at a predetermined timing, the control signal for forcibly maintaining the semiconductor switches at at least two different on-off combination settings (M2) one after another for a predetermine time per each on-off combination setting. Each time the predetermined time has elapsed, the control unit detects whether and which of abnormalities due to short-to-ground and short-to-supply has occurred in a motor power supply line connecting the motor to the driver unit, based on where an overcurrent is detected in the driver unit.

Abstract: Disclosed is a method for controlling an inverter. The method includes detecting an output current from an inverter to determine a software over-current suppression (S/W OCS) level according to an output frequency of the output current.

Abstract: The present invention pertains to the technological field of cooling compressors and, more specifically, relates to an anti-flame protection arrangement for the electrical connections of said cooling compressor. Problem to be solved: Ensure end-user safety of the compressor through a simple and inexpensive solution and preventing the maintenance and/or propagation of flames/fire in the region of the chamber defined by the protective cover of the electrical connections external to the compressor housing. Problem resolution: Accordingly, it is provided a cooling compressor including a protection arrangement for electrical connections integrated by a protective cover defining an electrical connections chamber external to the housing, the protective cover being physically associated with an anti-flame body, which defines a sealing portion, preferably making the electrical connections chamber hermetic in relation to an external environment.

Abstract: The present invention relates to a system and a method for independently controlling a relay using bimetal which allow bimetal to operate based on a signal output from a micro controller unit when current of a predetermined threshold or more flows on a circuit to allow current which flows between a battery and the relay to flow bypassing the bimetal to independently control the relay regardless of whether a circuit pattern is abnormal.

Abstract: Embodiments related to electrical connectors including superelastic components are described. The high elastic limit of superelastic materials compared to conventional connector materials may allow for designs which provide reliable connections and high frequency operation. Superelastic components also may enable connector designs with higher densities of connections. In some embodiments, a connector includes one or more superelastic elongated members forming the mating contacts of the connector. The superelastic elongated members deform within one or more conductive receptacles to generate a suitable contact force. The conductive receptacles may include a plurality of protrusions arranged to deflect the superelastic elongated members during mating. A superelastic component may also be provided in a receiving portion of a connector, and may form a portion of a conductive receptacle.

Abstract: A motor protection relay including a housing and a printed circuit board disposed within the housing, the printed circuit board including a central processing unit and a wireless communication interface, the wireless communication interface adapted to receive wireless communication signals for configuring operating parameters of the motor protection relay via the central processing unit.

Abstract: An inverter system includes: an inverter configured to receive utility AC power and step it up to a high-voltage power necessary for operation of a motor and supply the high-voltage power to the motor; a switch connected between the inverter and the motor and configured to be turned on and off such that an output voltage from the inverter is supplied to the motor or interrupted; a current detector configured to detect an output current from the inverter; and a controller configured to control the inverter system so that the inverter is interrupted if an output current value detected by the current detector is smaller than a predetermined reference current value for more than a predetermined reference duration.

Abstract: Erroneous mounting of a semiconductor power module can be more easily detected. A semiconductor power module (9) according to the present invention includes: a status signal generation unit (90) configured to detect a status in the semiconductor power module (9) and generate and output a status signal indicating the detected status; an identification information storage unit (91) configured to preliminarily store identification information for identifying the semiconductor power module (9) and output an identification signal indicating the identification information; and a switching unit (92) configured to select one of the status signal output from the status signal generation unit (90) and the identification signal output from the identification information storage unit (91) and output the selected signal to an outside of the semiconductor power module (9).

Abstract: A system and method for detecting cavitation in pumps for fixed and variable supply frequency applications is disclosed. The system includes a controller having a processor programmed to repeatedly receive real-time operating current data from a motor driving a pump, generate a current frequency spectrum from the current data, and analyze current data within a pair of signature frequency bands of the current frequency spectrum. The processor is further programmed to repeatedly determine fault signatures as a function of the current data within the pair of signature frequency bands, repeatedly determine fault indices based on the fault signatures and a dynamic reference signature, compare the fault indices to a reference index, and identify a cavitation condition in a pump based on a comparison between the reference index and a current fault index.

Abstract: A power-monitoring system and method is disclosed. The power monitoring system can comprise a surge arrester, a voltage-monitoring relay, a K1 relay, a reset switch, a K1 switch, a K2 relay, an F1 switch, a K2 switch, and a machine communication port. The K1 relay can activate when voltage-monitoring relay detects an electrical issue. The K2 relay can activate when surge arrester detects a current spike. A method for monitoring power is also disclosed. A surge arrestor and power-monitoring relay can monitor a supply line. The voltage-monitoring relay can activate K1 relay when it detects an electrical issue. The surge arrester can activate K2 relay when it detects a current surge.

Abstract: An electronic device is provided that may include a housing and an electronic component disposed within the housing. The housing may include a plug configured to engage a terminal assembly extending from a compressor shell and facilitate electrical communication between the plug and the terminal assembly. An exterior surface of the housing may include one or more receptacles extending therethrough in electrical communication with the electronic component.

Abstract: A switching module includes a switching element having a control terminal, electrically connected to a first conduction path including a reference terminal, to be opened and closed by controlling the switching element to be ON and OFF. The switching element is controlled in response to a voltage difference between the reference terminal and the control terminal. Moreover, the switching module includes determining unit that determines whether or not a conduction failure has been occurred between the control terminal and an outside the switching module; and reducing unit that reduces an absolute value of the voltage difference when the determining unit determines that the conduction failure has occurred, so as to forcibly turn OFF the switching element.

Abstract: A method for monitoring the temperatures of at least two semi-conductor power switches that are arranged on a common cooling body. Temperature detection is carried out by means of a temperature model each allocated to a switch, in which switch and operating parameters as well as temperature measurement values are processed for calculating the temperature and/or a temperature difference in the relevant switch. A temperature measurement value from a temperature sensor is used as an input parameter for the temperature model, the temperature sensor being centrally positioned between at least two switches and standing in a heat conducting connection with the cooling body. A related apparatus is an electronic temperature emitting power switch arrangement, having a temperature sensor positioned centrally between the two or between two switches each, the same being coupled in a heat conducting way with the cooling body and with the output side of the calculator.

Abstract: Systems and methods are provided for diagnosing stator windings in an electric motor. An exemplary method for diagnosing stator windings in an electric motor involves determining an input energy imbalance across phases of the stator windings for an electrical period of the electric motor and identifying a fault condition when the input energy imbalance is greater than a first threshold value. In some embodiments, an input energy ratio across phases of the stator windings is also determined for the electrical period, wherein the fault condition is identified as a phase-to-phase short circuit fault condition when the input energy ratio is greater than a second threshold value and the input energy imbalance is greater than the first threshold value, or alternatively, as an in-phase short circuit fault condition when the input energy ratio is less than the second threshold value.

Abstract: The motor monitoring system of the present disclosure uses several calculated monitoring values to determine a status of a motor and take a predetermined action when a threshold corresponding with the monitoring value is exceeded. The threshold may be calculated by an intelligent electronic device (IED) monitoring the motor. The predetermined action may include further monitoring of the motor. The predetermined action may include monitoring equipment not directly monitored by the IED.

Abstract: An electric motor (100) having a motor control system (400) including: —a current measuring means (402) for directly or indirectly measuring the electric current in the rotor windings (7) providing a rotor current value/s, —an ambient temperature measuring/estimation means (404) for measuring or estimating the ambient air temperature providing an air temperature value/s, —a rotor temperature estimation means (406, 407, 408, 409, 410, 411) for estimating a rotor temperature at least based on the rotor current value/s and the air temperature value/s, and—a current limiting means (405) for preventing overheating/burning of the rotor assembly (3) by limiting the electric current to the rotor windings (7) when the estimated rotor temperature exceeds a predetermined overheating threshold (412).

Abstract: A motor driven power steering (MDPS) may include: a vehicle speed sensor configured to sense vehicle speed; a temperature sensor configured to sense a temperature of a power pack; a current sensor configured to sense an amount of current applied to the MDPS; a storage unit configured to store a thermal resistance value based on the vehicle speed with respect to the temperature of the power pack; and a control unit configured to calculate an estimated temperature by reflecting the thermal resistance value based on the vehicle speed with respect to the temperature of the power pack and the current amount applied to the MDPS into a temperature estimation function, and drive a motor according to the calculated estimated temperature.

Abstract: A system includes a refrigerant compressor including an electric motor, a current sensor that measures current flow to the electric motor, a switching device configured to close and open to allow and prevent current flow to the electric motor, respectively, a maximum continuous current (MCC) device that includes a resistance corresponding to a maximum continuous current for the electric motor, and a motor protection module. The motor protection module communicates with the MCC device, the current sensor, and the switching device and determines a first MCC value for the electric motor as a function of the resistance of the MCC device. The motor protection module also selectively sets a predetermined MCC to the first MCC and controls the switching device based on a comparison of the current flow to the electric motor and the predetermined MCC.

Abstract: A control system for controlling power supply of an electric machine of an automobile and which contributes to movement thereof, wherein the control system is connected, at an input thereof, to a mechanism estimating a temperature of a rotor of the electric machine and to a temperature sensor measuring a temperature of a stator of the electric machine. The control system includes mappings of a set of values for allocating supply currents of the electric machine on the basis of torque and rotational speed request values received at the input of the control system, and includes a switching mechanism for selecting the mapping, the supply current signals of which are transmitted to the electric machine, on the basis of the signals from the mechanism estimating the temperature of the rotor and from the stator-temperature sensor.

Abstract: Physical layer device auto-adjustment based on power over Ethernet (PoE) magnetic heating. In one embodiment, information generated by a PoE module that is indicative of the PoE operation over the network cable (e.g., level of current, heating, etc.) is made available to the physical layer device (PHY). This information enables the PHY to infer a change in the level of inductance on the line. In response, the PHY can then adjust a characteristic of transmission by the PHY.

Abstract: Disclosed are alternate embodiments of various components of a barrier operator system. and methods of operation, including of the mechanical drive subsystem with segmented and self-locking rail unit, rail mounting supports, belt and chain drive tensioning, and drive assembly carriage and interface; the electronics and software routines for controlled operation of the various barrier operator functions; wall console communications with the barrier operator; encryption and decryption of access codes; establishment and monitoring of travel limits and barrier speed and force profiles; thermal protection of barrier operator drive motors; and establishment and control of communications from the barrier operator to accessories by way of a wireless adapter.

Abstract: An apparatus for dynamic braking is disclosed. The apparatus includes a first switch connected to a first connection of a dynamic braking resistor and to a first power bus of a motor controller. The apparatus includes a second switch connected to a second connection of the dynamic braking resistor and to a second power bus of the motor controller. The motor controller provides power to and controls a motor. The apparatus includes a switch control module that controls the first and second switches to connect the dynamic braking resistor to the first and second power buses. The switch control module controls the first and second switches in response to a signal from the motor controller.

Abstract: An overload prevention system and method for an electric circuit having a plurality of components is disclosed, where each component has a set of pre-computed parameters. For each component, monitored parameters are observed; a limited value is computed using the pre-computed and monitored parameters; and it is determined if the limited value reached a limit. If the limited value reaches the limit; the system limits one of the monitored parameters. Pre-computed parameters can include time constant and rated current; monitored parameters can include current; and limited value can be component temperature. A time constant, rated current and rated temperature can be pre-computed such that the temperature stays at or below the rated temperature when the current is substantially equal to the rated current. Per unit values can also be used such that per unit temperature stays at or below unity when per unit current is substantially equal to unity.

Abstract: A controller controls switching of IGBT devices of an inverter according to the desired output of the permanent magnet motor. The controller includes: a magnet temperature detection device that detects the magnet temperature of the permanent magnet motor based on the output of a temperature sensor; a setting device that sets a threshold value of the magnet temperature corresponding to the desired output of the permanent magnet motor, based on a predetermined relation between the output from the permanent magnet motor and a critical temperature, up to which demagnetization in the permanent magnet motor is not caused; and a carrier frequency control device that, when the magnet temperature detected by the magnet temperature detection device exceeds the threshold value, changes the carrier frequency, at which the IGBT devices are switched, such that a ripple current superimposed on a motor current that flows through the permanent magnet motor is reduced.

Abstract: A protection circuit includes first and second field-effect transistors (FETs), a bipolar junction transistor, first to sixth resistors, and a first capacitor. The protecting circuit is connected between a power supply unit and a fan, for powering on or powering off the fan.

Abstract: A system includes a refrigerant compressor including an electric motor, a current sensor that measures current flow to the electric motor, a switching device configured to close and open to allow and prevent current flow to the electric motor, respectively, a maximum continuous current (MCC) device that includes a resistance corresponding to a maximum continuous current for the electric motor, and a motor protection module. The motor protection module communicates with the MCC device, the current sensor, and the switching device and determines a first MCC value for the electric motor as a function of the resistance of the MCC device. The motor protection module also selectively sets a predetermined MCC to the first MCC and controls the switching device based on a comparison of the current flow to the electric motor and the predetermined MCC.

Abstract: A three-phase electric motor of a compressor receives first, second, and third phases from a three-phase power supply. A method for protecting the motor includes, using a line break protector, disconnecting the motor from only the first phase in response to a temperature being greater than a predetermined temperature threshold. The method also includes measuring a first current flowing through the line break protector, and determining a current value based on the first current independent of current in the second and third phases. The method further includes disconnecting the motor from the first, second, and third phases in response to the current value being less than or equal to a predetermined threshold.

Abstract: The motor monitoring system of the present disclosure uses several calculated monitoring values to determine a status of a motor and take a predetermined action when a threshold corresponding with the monitoring value is exceeded. The threshold may be calculated by an intelligent electronic device (IED) monitoring the motor. The predetermined action may include further monitoring of the motor. The predetermined action may include monitoring equipment not directly monitored by the IED.

Abstract: A system for protecting a three-phase electric motor of a compressor, the motor receiving first, second, and third phases from a three-phase power supply, the system including a single-phase line break protector, a first current sensor, and a control module. The single-phase line break protector disconnects the motor from the first phase in response to a temperature being greater than a predetermined temperature threshold. The first current sensor measures a current through the single-phase line break protector. The control module determines a current value based on the measured current, and disconnects the motor from the second and third phases in response to the current value being less than or equal to a predetermined threshold.

Abstract: A torque limit section that applies limit to a torque instruction value of an electric motor such that a switching elements temperature is restricted to no more than an element upper limiting temperature includes a torque restriction section that finds a torque restriction value for restricting the torque of the electric motor in accordance with the said switching elements temperature; a torque restriction mitigation section that finds a torque restriction mitigation value for mitigating the torque limit value in accordance with the integrated value of the deviation of the element upper limiting temperature and the switching elements temperature; a first subtractor that finds a torque restriction value by subtracting the torque restriction mitigation value from the torque limit value; and a second subtractor that finds a limited torque instruction value obtained by subtracting the torque limit value from the torque instruction value and outputs this to the gate generating section.

Abstract: In an abnormality diagnosing system for first and second current sensors for measuring a current, an obtaining unit obtains at least one pair of measured values of the first and second current sensors. The at least one pair of measured values is measured by the first and second current sensors at a substantially same timing. A diagnosing unit diagnoses whether there is an abnormality in at least one of the first and second current sensors based on a function defining a relationship between the at least one pair of measured values of the first and second current sensors.

Abstract: A motor detecting and protecting apparatus electrically connected with a motor. The motor detecting and protecting apparatus includes a detecting unit, an error determining unit, a controlling unit and a driving unit. The detecting unit detects a state of the motor and outputs at least one first detecting signal and at least one second detecting signal to the error determining unit. The error determining unit has a first predetermined value, wherein the error determining unit outputs a warning signal to the controlling unit while a variation value between the first detecting signal and the second detecting signal exceeds the first predetermined value. And the controlling unit will control the motor to stop operating by the driving unit in accordance with the warning signal. And a motor detecting and protecting method is also disclosed.

Abstract: A power circuit protection and control device simulator emulates in real time identical circuit protection and control functions performed by the actual device being simulated and generates real time simulated operational information concerning at least one of the device or the power circuit. A human-machine interface, such as through a web browser, allows a user to input power circuit operational parameters, such as motor current and load, and device variable circuit protection and control operational parameters, such as trip class, ground fault detection or phase unbalance protection. The simulator displays in real time simulated operational information on the human-machine interface. The simulator may be used to simulate operation of an electronic overload relay and an electric motor controlled by the relay.

Abstract: An apparatus which estimates the temperatures of a motor without using a temperature sensor can achieve overheat protection by proper control. In an example, a heat generation amount calculation section calculates a heat generation amount of a motor. A current upper limit map has a current upper limit value corresponding to a temperature estimated value and a ratio map has a ratio corresponding to the temperature estimated value. A lower one of limited current values, determined using the two maps, controls energization of the motor. The heat generation amount calculation section includes a heat generation correction term, and a heat radiation correction term for calculating a function of the difference between the integrated value of the heat generation amount and a motor ambient temperature. If the ambient temperature becomes equal to or higher than a comparison temperature, then the heat generation amount is calculated without the heat radiation correction present.

Abstract: A heat source apparatus in which a control device of the heat source apparatus can ascertain a stoppage of an inverter device and in which a stable operating time of the heat source apparatus can be extended is provided. The heat source apparatus includes an electric compressor that is driven by an inverter device and that compresses a refrigerant, the inverter device having a protective function that performs stoppage for device protection on the basis of a predetermined calculation by an inverter control portion, and a control device that controls cold output and/or heat output. The control device includes an inverter-protective-function estimating unit that estimates a calculation result of the protective function of the inverter control portion.

Abstract: A motor control device includes a motor, a control portion controlling the motor, estimating a heating temperature of the motor on the basis of an electric current value and an energizing time period or a stopping time period of the motor, and restricting an electrification of the motor in a case where the estimated heating temperature becomes equal to or greater than a limit value, and a temperature sensing device for detecting a temperature of a predetermined portion of a vehicle, wherein the control portion estimates an initial temperature of the motor when an engine is started on the basis of a temperature signal outputted from the temperature sensing device and determines the limit value on the basis of the estimated initial temperature.

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: 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 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: Methods and apparatus are provided for operation of a voltage source inverter. A method of operating a voltage source inverter having an output with multiple voltage phases having a DC voltage level, the method comprising sensing a low output frequency condition; determining a DC voltage offset responsive to the low output frequency condition; and applying the DC voltage offset when operating the voltage source inverter resulting in a change to the DC voltage level of the multiple voltage phases.

Abstract: In a method for operating a household appliance having at least one electrical consumer activated by power electronics an actual value representing a temperature loading of the power electronics is determined and compared with a limit value representing a maximum tolerable temperature loading of the power electronics in normal load operation. When the actual value is below the limit value; an overload operation is enabled at least temporarily with a higher power than in normal load operation.

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 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: A circuit breaker with overload and short-circuit protection functions for a motor, on which is mounted a thermally actuated overload tripping device including an adjustment dial to set a value corresponding to a rated current value of the motor on a scale. The dial has a standard setting pointer mark and a correction setting pointer mark side-by-side along a perimeter. The standard setting pointer mark applies to using the circuit breaker as a single item. The correction setting pointer mark applies to using a number of circuit breakers arranged in a line in close contact with each other. By setting a mark selected according to the arrangement of the circuit breaker at the rated current value, the steady state current value of the tripping device can be adequately set to correspond to the rated current value of the motor.