Abstract: Even when one power conversion device among a plurality of power conversion devices connected in parallel experiences a short circuit, the other power conversion devices having experienced no short circuit can be promptly restarted. Each power conversion device includes: a short circuit occurrence determination unit configured to determine, on the basis of a current value at an output terminal, whether or not a short circuit has occurred; a short circuit elimination determination unit configured to determine, on the basis of a current value and a voltage value at the output terminal, whether or not the short circuit has been eliminated; and a current interruption unit configured to, on the basis of determination by the short circuit occurrence determination unit and determination by the short circuit elimination determination unit, interrupt current that flows from a power conversion unit to the output terminal or cancel the interruption.

Abstract: According to an embodiment, a current monitoring circuit includes a signal shaping unit configured to receive a current sense signal and provide a modified current signal; a filter configured to receive the modified current signal and to provide a respective filtered signal; a comparator configured to receive the filtered signal and a threshold value and to indicate when the filtered signal exceeds the threshold value. The signal shaping unit is configured to calculate a level of the modified current signal from a corresponding level of the current sense signal in accordance with non-linear function.

Abstract: Even when a large current is intentionally flowed during a high-temperature conduction of a semiconductor element, there is a problem in that an overcurrent state is detected to stop current. In the present invention, an overcurrent detector 4 detects overcurrent when an input voltage Vin reaches a threshold voltage Vth, and outputs an overcurrent detection signal c to a gate driving unit 3. On the other hand, when a temperature detection signal a and a current control signal b are input, a transistor 52 is conducted, and the input voltage Vin of the overcurrent detector 4 becomes zero. In this case, the input voltage Vin of the overcurrent detector 4 does not reach the threshold voltage Vth. Therefore, the output of the drive signal output from the gate driving unit 3 is not stopped. For this reason, a large current can flow in a drain current Ids.

Abstract: A hot-swap circuit for providing soft start and overcurrent protection to an electronic circuit may include a controller and a timer. The controller may be configured to sense an electrical current associated with the hot-swap circuit, based on the electrical current sensed, perform current limiting of the electrical current to minimize inrush current to the electronic circuit, and disable the electrical current from flowing to the electronic circuit in response to the electrical current exceeding an overcurrent threshold for longer than a duration of a fault timer. The timer circuit may be configured to, for a period of time after enabling of the hot-swap circuit, cause the duration of the fault timer to be a first duration, and after the period of time, cause the duration of the fault timer to be a second duration significantly shorter than the first duration.

Abstract: A transistor diagnostic circuit includes a protection transistor output terminal, a fault terminal, and circuitry coupled to the protection transistor output terminal and the fault terminal. The protection transistor output terminal is adapted to be coupled to a current terminal of a protection transistor. The transistor diagnostic circuit is configured to, at start-up, load the protection transistor output terminal to test the protection transistor, and to generate a fault signal at the fault terminal responsive to a voltage on the protection transistor output terminal exceeding a threshold.

Abstract: A power distribution monitoring system is provided that can include a number of features. The system can include a plurality of monitoring devices configured to attach to individual conductors on a power grid distribution network. In some embodiments, a monitoring device is disposed on each conductor of a three-phase network and utilizes a split-core transformer to harvest energy from the conductors. The monitoring devices can be configured to harvest energy from the AC power grid. In some embodiments, the monitoring devices are configured to draw a ratiometric current to maintain an output resistance that equals an input resistance. Methods of installing and using the monitoring devices are also provided.

Abstract: A switching power supply includes: a DC-DC converter including a switching element and configured to output electric power input from an input terminal to an output terminal; a current detector configured to detect a load current output to the output terminal and to output a voltage corresponding to the load current as a detection result; a time constant circuit having a predetermined charging time constant; a time constant circuit controller configured to be connected to the current detector and the time constant circuit and configured to output a charging current based on the detection result to charge the time constant circuit or discharge charge charged in the time constant circuit as a discharging current on based on a comparison between the detection result output by the current detector and a reference voltage.

Abstract: An information handling system includes a current detector module and a baseboard management controller (BMC). The current detector module is configured to detect current slew-rate for an element of the information handling system, to determine that the current slew-rate is greater than a current slew-rate threshold, and to provide an indication that the current slew-rate is greater than the current slew-rate threshold on a communication interface. The BMC may enter an item into a log of the information handling system in response to receiving an indication.

Abstract: A method of over-current protection includes: determining a current flowing through a first element to be protected, comparing the determined current with a plurality of thresholds, controlling a counter based on the comparing the determined current with a plurality of thresholds, and stopping the current flowing through the first element by activating a switch in series with the first element when an output of the counter reaches a predetermined counter threshold.

Abstract: A switching device includes: an electronic trip unit; an actuator; a switching mechanism connected via the actuator to the electronic trip unit; a stationary contact; a mobile contact, which is coupled to the switching mechanism; and an alarm module. The alarm module includes: a first, a second, and a third connector; a first relay having a first contact which is connected to the first connector and having a second contact which is connected to the second connector; a second relay with a first contact which is connected to the third connector; and a control unit which is coupled on an output side to a control side of the first relay and to a control side of the second relay, and on the input side to the electronic trip unit.

Abstract: A power distribution apparatus includes a power source terminal, a power-distributing module, at least a power distribution module, an input detection unit, at least an output detection unit and a management unit. The power source terminal receives an input power. The power-distributing module converts the input power into an output power. Each of the power distribution modules includes a plurality of output ports. The power distribution module receives the output power to output the output power through the output ports. The input detection unit detects the input power to generate a set of input information. The output detection unit detects the output power to generate at least a set of output information correspondingly. According to the input information or the output information, the management unit controls the output ports to be turned on or off correspondingly.

Abstract: In the field of electrical power systems there is provided a method of supervising the operation of a plurality of current transformers that are arranged in respective current transformer within differing protection zones of a multi-phase electrical power system. The method of supervising comprises the steps of: (a) identifying a faulty protection zone within the electrical power system; (b) identifying a faulty current transformer group within the faulty protection zone; and (c) identifying faulty phase(s) within the faulty current transformer group within the faulty protection zone.

Abstract: A power switching control device includes a voltage measurement unit to measure a power-source-side voltage of a circuit breaker and a load-side voltage of the circuit breaker, an inter-pole-voltage estimation unit to estimate a future inter-pole voltage from a value of the power-source-side voltage and a value of the load-side voltage, a target closing-clock-time determination unit to set a target activation point of the circuit breaker on a waveform of an absolute value of the future inter-pole voltage, set an inter-pole withstand-voltage characteristic line calculated from a rate of decrease of dielectric strength, so that the inter-pole withstand-voltage characteristic line passes through the target activation point, and determine a clock time when the inter-pole withstand-voltage characteristic line becomes zero as a target closing clock time of the circuit breaker, and a closing control unit to close the circuit breaker at the target closing clock time.

Abstract: In a power supply control apparatus, if a switching signal input from a microcomputer to a control circuit instructs switching on of a semiconductor switch, when an input voltage that is input to the drain of the semiconductor switch is higher than or equal to a predetermined voltage, the control circuit drives a charging circuit. The charging circuit charges a capacitor (Cs) via a diode (D1). Accordingly, a voltage at the gate of the semiconductor switch taking a potential at the source of the semiconductor switch as a reference becomes higher than or equal to a predetermined voltage, and thus the semiconductor switch is switched on. While driving the charging circuit, the control circuit keeps driving the charging circuit even if the input voltage becomes lower than the predetermined voltage.

Abstract: The present disclosure relates to a solid state power controller, comprising: a power switch for interrupting a line; a current sensor for measuring a current flow on the line; and a control unit for controlling the power switch and that is configured to prevent a time-dependent overcurrent on the line on the basis of the current measured by the current sensor, wherein the control unit comprises a counter that is adapted to increment a count when the measured current is larger than a threshold value and to decrement the count when the measured current is smaller than the threshold value; and wherein the power switch is adapted to interrupt the line when the counter reaches or exceeds a predefined count.

Abstract: A circuit protection device having operational parameters configurable only via a separate programming device includes a memory configured to receive a selector identifying one of a plurality of operational parameters to be adjusted, and to receive a parameter value from the programming device. A processor is coupled to the memory and is configured to receive the selector from the memory, select the operational parameter of the circuit protection device based on the selector, and to receive a parameter value for the operational parameter from memory, and set the selected operational parameter to the parameter value.

Abstract: A method for interrupting a current of an electrical power supply line includes integrating a supply line signal of the electrical power supply line over a predetermined time period to obtain an integrated signal, determining whether the integrated signal meets a predetermined condition, and using a current interrupting element to interrupt the current if the integrated signal meets the predetermined condition.

Abstract: The present disclosure relates to a controller, a circuit and method for controlling a power converter using pulse width modulation (PWM). At least one logic block (13, 15, 16) of the controller is configured to remove a command (4) which is configured to control the other power semiconductor switch (2) in a half-bridge (1,2) so that the other power semiconductor switch (2) remains in a non-conductive state while an antiparallel diode (6) allows an electric current (5) to pass in one direction, called the diode's forward direction, while blocking current in the opposite direction. In case the diode (6) is conducting instead of the other power semiconductor switch during the duration of the state of the command, the switching command (4) for the latter is omitted.

Abstract: The present disclosure is directed to a method for detecting a failure in a signal light. In one embodiment, the method includes monitoring operation of one or more light emitting diodes (LEDs) of the signal light coupled to a constant current driver, detecting a short circuit in at least one of the one or more LEDs and signaling a failure in the signal light when the short circuit is detected.

Abstract: A voltage sensing circuit of a converter senses input and output voltages of a converter with only one sensing circuit. The voltage sensing circuit is capable of reducing the number of the components for a controller and the volume thereof to save cost, and detecting whether the discontinuous mode (DCM) is entered or not, thereby to apply a separate control algorithm thereto when the DCM is entered.

Abstract: A power system includes main circuit interrupters each having a load output, feeder circuit interrupters, a number of tie circuit interrupters, and a circuit. The circuit is structured to block communication, at least when at least one of the tie circuit interrupters has an open state between a first and a second of the main circuit interrupters, of a zone selective interlocking output of one of the feeder circuit interrupters having a line input electrically connected to the load output of the first main circuit interrupter to a zone selective interlocking input of the second main circuit interrupter, and of a zone selective interlocking output of a different one of the feeder circuit interrupters having a line input electrically connected to the load output of the second main circuit interrupter to a zone selective interlocking input of the first main circuit interrupter.

Abstract: A power supply circuit, an antenna control system, and a digital communication device are provided. The power supply circuit is adapted to supply electronic power to an antenna and includes a power management circuit and a pin. The power management circuit is coupled between a power input terminal and a power output terminal. In a first mode, the pin receives a mode control signal to control the power management circuit to deliver or not deliver electronic power of a power source from the power input terminal to the power output terminal. In a second mode, the pin stops receiving the mode control signal and provides a detection signal, which indicates whether the power supply circuit is overloaded. Thereby, power switching of the antenna and an overload detection/notification function are accomplished by using the single pin.

Abstract: A protection and attenuation circuit for sensitive AC loads is described. The circuit provides AC power protection and attenuation utilizing high-efficiency switch-mode techniques to attenuate an AC power signal by incorporating a bidirectional, transistorized switch driven from a pulse width modulation signal, PWM. The circuit monitors characteristics of the AC power signal driving a known load and characteristics of the load or other elements and determines the duty cycle of the pulse width modulated signal, PWM, based upon the duration and amplitude of the over-voltage, over-current, over-limit or other event.

Abstract: A method of controlling the opening or the closing of an AC electric circuit in an electricity meter by means of a relay is provided. The method times relay activation commands so as to take account of the inertial delay (di) of the relay, in such a manner that the actual activation command applied to the relay causes the relay actually to take action on the electric circuit when an electrical parameter of said circuit reaches a zero value, in order to limit the formation of electric arcs in the relay.

Abstract: The fault current detecting circuit includes: a current detection unit that outputs a current detection signal; a first comparing circuit unit that compares the current detection signal with a predetermined reference current value and outputs a first output signal; a differentiator that differentiates the current detection signal to output a change slope of the current detection signal; a second comparing circuit unit that compares the change slope with a predetermined reference change slope value and outputs a second output signal; a third comparing circuit unit that compares the current detection signal with a predetermined current detection limit reference value and output a third output signal; and a trip determining unit that outputs a trip control signal only when the first output signal and the second output signal are maintained to be received and the third output signal is not received.

Abstract: A power supply circuit and method for supplying power are provided. The power supply circuit includes a front end circuit, a power factor correction circuit, and a drive circuit. The front end circuit is configured to generate a direct current voltage based on an input voltage. The front end circuit includes a first surge protection circuit. The power factor correction circuit is configured to generate a driving voltage based on the generated direct current voltage. The power factor correction circuit includes a second surge protection circuit and an over-temperature protection circuit. The drive circuit is configured to generate an output voltage for a load based on the driving voltage. The drive circuit includes a third surge protection circuit, a startup circuit, and an open-circuit protection circuit.

Abstract: A negative current protection system for a low side switching converter FET, for use with a switching converter arranged to operate high and low side FETs connected to an output inductor to produce an output voltage. The negative current protection system includes a current sensing circuit which produces an output Vcs that varies with the current in the high side FET, a negative current threshold generator which produces a threshold signal ?Ith which represents the maximum negative current to which the low side FET is to be subjected, and a comparison circuit arranged to compare the valley portion of Vcs and -Ith and to set a flag if Vcs<?Ith at a predetermined time in the switching cycle—typically after the converter's blanking time. When the flag is set, the system preferably responds by adjusting the operation of the switching FETs to reduce the negative current.

Abstract: The present invention provides a protection circuit. The protection circuit includes an output stage circuit and a feedback unit that generates a first current. Under a first condition that the first current is one of currents larger than and equal to a rated current and the first condition remains for a first period, the feedback unit controls the output stage circuit to restrict the first current. Under a second condition that the first current is one of currents larger than and equal to a restriction current and the second condition remains for a second period, the feedback unit controls the output stage circuit to terminate the first current.

Abstract: Disclosed is a power off device which includes a micro arc detector for turning on a first switching element, based on a voltage induced in a high frequency choke coil by a high frequency pulse current caused by micro arc at a power line, a high current arc detector for outputting a high current arc detection current during turning-on of a second switching element made based on variation of a magnetic field generated at a coil, a delay unit for accumulatively charging the micro arc detection current or the high current arc detection current in a delay capacitor at a predetermined time constant, a power off unit for electrically disconnecting a load from the power line when an operating voltage is applied, and a first switch for connecting the operating voltage to the power off unit in response to the arc detection signal.

Abstract: A delay protection circuit is installed between a power supply unit and a load of an electronic device, and includes a first capacitor and second capacitors. The delay protection circuit allows the supply of electric power to the load by the PSU, and detects power being output by the PSU. If the power output by the PSU exceeds a rated power of the load, the first capacitor becomes chargeable by the PSU, and the load is electrically disconnected from the PSU once a voltage on the first capacitor achieves a predetermined voltage level. The second capacitors are also available for charging by the PSU according to a difference between the power being output by the PSU and the rated power of the load to provide automatic adjustability of a delay time for the voltage on the first capacitor to achieve the predetermined voltage.

Abstract: In one aspect, a method of electrical arc fault detection when high frequency (e.g., RF noise) is present is disclosed. The method includes determining if first arcing criterion is met, determining if delay criterion is met, implementing a delay for a delay period if the delay criterion is met, and determining if second arcing criterion is met. If the second arcing criterion is met, then a trip signal may be sent to trip the circuit breaker. In another aspect, the method includes determining if first arcing criterion is met, starting delay period if the first arcing criterion is met, determining if delay criterion is met, and if the delay criterion is met, determining if second arcing criterion is met. An arc fault detection apparatus adapted to carry out the methods, and systems including the arc fault detection apparatus are disclosed, as are various other aspects.

Abstract: A module hot swap circuit includes a low voltage-drop rectifier adapted to receive either positive or negative voltages of different absolute values. The rectifier is coupled to a power manager that provides dual startup/shutdown voltage thresholds and inrush current limiting. A detector prevents reverse current flow allowing the module to hold up during input voltage drop-outs.

Abstract: An apparatus and a method for recognizing an error in a power bridge circuit containing a load, a high-side branch and a low-side branch. Accordingly, a first switched current source is connected to the load and to a diagnosis connection for a high-potential of a diagnosis voltage, a second switched current source is connected to the load and to a diagnosis connection for a low-potential of the diagnosis voltage, and a control device for controlling the first switched current source and the second switched current source. The control device switches on one of the switched current sources when the high-side power switch and the low-side power switch are open, while the other switched current source is switched off. A testing device tests a voltage at the load when one of the switched current sources is switched on and the other of the switched current sources is switched off.

Abstract: A circuit interrupting device having an auto-monitoring circuit for periodically testing various functions and structures of the device. The auto-monitoring circuit initiates an auto-monitoring routine which, among other things, generates a self-test fault condition and determines whether the detection mechanisms within the device properly detect the self-test fault. Processing an early detection signal determines whether the self-test fault was properly detected without interfering with the normal operation of the detection circuitry and without causing a false trip within the device. Additional functionality of the auto-monitoring circuit permits automatic verification that the device is properly wired, that is, not miswired, and determines whether the device has reached the end of its useful life.

Abstract: An electronic circuit breaker including a two stage detection mechanism; an instantaneous trip operating at a first threshold and a delayed trip such operating at a second lower threshold. This is advantageous in maintaining operation during very short transient load peaks, which do not warrant isolation from the supply. The breaker can be line powered, can be reset remotely by controlling the line power, and can be implemented entirely in solid state electronics. As such it requires little or no service or maintenance.

Abstract: An apparatus and method for protecting a power system comprising a generator providing power to an alternating current bus, a power converter for converting alternating current power on the alternating current bus to direct current power on a direct current bus, and a direct current load powered by the direct current power on the direct current bus. An undesired condition is identified at the input to the power converter from the alternating current bus. The undesired condition is caused by at least one of the power converter, the direct current bus, or the load. The power converter is disconnected from the alternating current bus in response to identifying the undesired condition for at least a time delay. The time delay is selected such that the power converter is disconnected from the alternating current bus before the alternating current bus is disconnected from the generator due to the undesired condition.

Abstract: A system for supplying an electrical system with direct current, the system including at least two direct current power supply devices each having means of electrical connection to an alternating current power supply source and an AC/DC converter of alternating current into direct current, a module for managing the power supply of the electrical system which, after reception of an information of failure of a first active power supply device, transmits a command to start up a second inactive power supply device and a back up electrical energy storage device electrically by-pass connected between the power supply devices and the electrical system. The management module also receives the information of failure from the back up device and/or from the electrical system and transmits the command to start up the second power supply device during a discharge phase of the back up device.

Abstract: An appliance includes a plurality of electrical loads and a load control circuit including at least a clock enable circuit and a full power timer. The clock enable circuit is configured and operatively connected to activate the full power timer when all of the loads are energized, and the full power timer is configured and operatively connected to de-energize at least one load selected from the plurality of loads on reaching a predetermined full power time limit.

Abstract: A fuse box system and method providing for visual and/or remote sensing of interrupted fusing elements is disclosed. The system incorporates LEDs and/or remote sensing apparatus to permit indication of a “blown” fuse and/or circuit protection breaker. This system may be configured for both polarized and/or non-polarized applications and generally provides for indicator illumination when a fuse/breaker is blown. Some preferred embodiments may incorporate current sourcing technologies to permit operation of the system over wide range of system voltages, as well as provisions for wired and/or RF/wireless interrogation of the fuse/breaker status. Alternate embodiments including systems/methods to permit remote sensing of fuse status and/or circuit current monitoring, and may be retrofit within existing fuse/breaker panel systems in some configurations.

Abstract: A method and an arrangement for reducing an in-rush current of a multi-module system are provided. The system comprises a plurality of modules designed to perform predefined functions, and a power supply unit designed to provide power to the plurality of modules. Each of the plurality of modules comprises a power control system which performs a respective time delay on the power-on of the power received from the power supply unit. With the system and the method, the total in-rush current of the multi-module system is greatly reduced.

Abstract: There is provided a protection apparatus for a load circuit, capable of protecting the load circuit by simulating a fuse. A pseudo heat capacity Cth* smaller than a heat capacity of an electric wire used in the load circuit is set, and a temperature of the electric wire is calculated with reference to an arithmetic expression of heat generation amount of the electric wire, an arithmetic expression of heat radiation amount of the electric wire, a time counted by the count unit, and the pseudo heat capacity Cth*. Then, a semiconductor relay S1 is interrupted when the calculated temperature of the electric wire reaches an allowable temperature of the electric wire to protect the load circuit from heat generation.

Abstract: A circuit interrupter apparatus includes circuit interrupter and a device. The circuit interrupter includes separable contacts, an operating mechanism structured to open and close the separable contacts, and a trip mechanism cooperating with the operating mechanism to trip open the separable contacts. The trip mechanism includes a zone selective interlocking input and a zone selective interlocking output. The device includes a first input electrically interconnected with the zone selective interlocking input, a second input electrically interconnected with the zone selective interlocking output, and an indicator circuit structured to indicate that the zone selective interlocking input occurred at the first input or that the zone selective interlocking output occurred at the second input.

Abstract: A system comprises an AC/DC adapter having a connector. The system also comprises a portable computer that receives said connector. The portable computer comprising a delay circuit coupled to a power transistor that is coupled in parallel with a resistor. The delay circuit causes the power transistor to activate following a time delay after current from the adapter begins to flow through the resistor. As a result of a user beginning to remove the connector from the portable computer, a control transistor is activated to reset the delay circuit.

Abstract: The present invention is directed to a method and a system for fault detection analysis in a power device which is operatively associated with a differential protection unit. The power device has one input side and one output side through which an input current and an output current flows into and out from it, respectively. Signals representative of the input and output currents are processed in order to verify if an occurring fault is external to the power device. Under a condition of an external fault, the differential protection unit is disabled for a determined interval of time.

Abstract: Whether there is a defect such as chipping of a die or separation of a resin in a wafer level package is electrically detected. A peripheral wiring is disposed along four peripheries of a semiconductor substrate outside a circuit region and pad electrodes P1-P8. The peripheral wiring is formed on the semiconductor substrate and is made of a metal layer that is the same layer as or an upper layer of a metal layer forming the pad electrodes P1-P8, or a polysilicon layer. A power supply electric potential Vcc is applied to a first end of the peripheral wiring, while a ground electric potential Vss is applied to a second end of the peripheral wiring through a resistor R2. A detection circuit is connected to a connecting node N1 between the peripheral wiring and the resistor R2, and is structured to generate an anomaly detection signal ERRFLG based on an electric potential at the connecting node N1.

Abstract: A circuit breaker with a time-delay function, including a first circuit breaking unit, a remote control unit comprising a time-delay control circuit, and a housing. The first circuit breaking unit and the remote control unit are disposed in the housing, the first circuit breaking unit operates to switch on or off loads and electric lines, the remote control unit operates to control interruption of the circuit breaker with a time-delay function via a remote control signal, the time-delay control circuit operates to implement time delay after the remote control unit receives the remote control signal and before the first circuit breaking unit switches on or off the loads and the electric lines, and the housing is made of insulating and flame-retardant materials.

Abstract: A protection apparatus of a load circuit, comprises: a temperature estimation unit configured to estimate a temperature of an electric wire based on a pseudo-temperature arithmetic expression; and a breaking control unit configured to break a switch portion when the temperature estimated by the temperature estimation unit has reached an allowed temperature of the electric wire. The pseudo-temperature arithmetic expression is set in such a manner that, in a temperature arithmetic expression of the electric wire, the temperature arithmetic expression using the elapsed time counted by the timer, the current detected by the current detection unit, and a heat capacity and conductor resistance of the electric wire, a pseudo-heat capacity smaller than the heat capacity of the electric wire is assigned to the heat capacity, and a pseudo-conductor resistance larger than the conductor resistance of the electric wire is assigned to the conductor resistance.

Abstract: A protection apparatus of a load circuit sets a threshold temperature at a lower temperature than an allowed temperature of an electric wire for use in the load circuit, and estimates a temperature of the electric wire based on an ambient temperature, a load current and a time while the load current is flowing through the electric wire. Then, in the case where the estimated temperature has reached the threshold temperature, a semiconductor relay (S1) is broken. As a result, in the case where such an electric wire temperature has risen owing to an occurrence of an overcurrent, and the like, the circuit is surely protected at the point of time before the electric wire temperature reaches the allowed temperature. Therefore, a fuse used in a conventional load circuit becomes unnecessary.

Abstract: The system of the invention includes a circuit breaker switching control section (100) and a setting control section (700) connected therewith through a communication network (500). The circuit breaker switching control section (100) transmits a circuit breaker state quantity acquired by a signal input section (120) through the communication network to a set value calculation section (740) of the setting control section (700). The set value calculation section (740) of the setting control section calculates a set value to be set in the switching control section (100) of the circuit breaker, using the state quantity of the circuit breaker that was transmitted thereto. The setting control section (700) transmits to the circuit breaker switching control section the set value calculated by the set value calculation section (730) through the communication network.

Abstract: An input circuit includes an interface structured to output a logic signal from an alternating current signal of a pair of elongated conductors. A load is switchable to the elongated conductors. A processor outputs a control signal to switch the load to the elongated conductors asynchronously with respect to the alternating current signal for a first predetermined time, inputs the logic signal, determines if the input logic signal is active a plurality of times during the first predetermined time and responsively sets a first state of the alternating current signal, and, otherwise, sets an opposite second state of the alternating current signal, and delays for a second predetermined time, which is longer than the first predetermined time, for the opposite second state before repeating the output, and, otherwise, delays for a third predetermined time, which is longer than the second predetermined time, for the first state before repeating the output.