Abstract: A circuit breaker comprises a magnetic trip mechanism configured to provide a first mechanical driving force, a low voltage trip mechanism configured to provide a second mechanical driving force, a first micro switch configured to generate and output a first trip signal indicating that the circuit breaker has performed a trip operation due to the occurrence of a fault current on a circuit, a second micro switch configured to generate and output a second trip signal indicating that the circuit breaker has performed a trip operation due to the occurrence of a low voltage on the circuit, a first driving force transmission mechanism configured to transmit the first mechanical driving force from the magnetic trip mechanism to the first micro switch, and a second driving force transmission mechanism configured to transmit the second mechanical driving force from the low voltage trip mechanism to the second micro switch.

Abstract: Disclosed herein is an overvoltage protection apparatus and method of a high voltage inverter adapted to protect a load without any adverse effect from an overvoltage aroused by voltage fluctuation attributable to an impedance difference among an inverter, a load and a cable connected between the inverter and the load, wherein the apparatus and method converts a voltage command signal given as a digital signal into an analog reference signal by a main control unit, compares the analog reference voltage with a sawtooth wave having a predetermined voltage level and frequency in order to generate a PWM (Pulse Width Modulation) signal, determines the pulse width of the PWM signal, and converts the pulse width of the PWM signal to have a predetermined time interval in a case the pulse width of the PWM signal is less than a predetermined time interval.

Abstract: An RFID tag and an RFID tag using the same are disclosed, wherein the RFID tag comprises: a circuit unit arranged on a first part of a board; and a loop type antenna on a second part of the board.

Abstract: Disclosed is a high voltage relay having an enhanced air-tight structure, the relay including a molded case formed by molding a synthetic resin having an electric insulating property into a box shape having one open surface, an actuator accommodated in the lower molded case, and an arc extinguishing mechanism allowing insertion of a stationary electrode therein and installed on the actuator for covering the open surface of the molded case, the arc extinguishing mechanism including a gas discharge hole portion blocked when a thermosetting resin coated on the arc extinguishing mechanism for air-tightness is hardened.

Abstract: The present invention relates to a control device and a control method of a high voltage inverter capable of automatically and accurately setting up neutral point information at a master controller and a plurality of cell controllers of the high voltage inverter, wherein a master controller determines information of neutral point set up to itself and performs a communication with the cell controllers each disposed at each of a plurality of U phase unit cells, a plurality of V phase unit cells and a plurality of W phase unit cells to determine the neutral point information preset on the cell controllers and to detect a cell controller set up with neutral point information different from that of the master controller, and to correct the neutral point information of the detected relevant cell controller using the neutral point information set up in the master controller, thereby operating the high voltage inverter.

Abstract: A water-cooling type cooler and an inverter employing the same are disclosed. A guide pin for distributing cooling water is formed in the middle of a cooling water flow path having a bent face, to make a flow rate of cooling water at the bent portion of the cooling water flow path uniform to thus improve cooling performance of the water-cooling type cooler. In addition, because the cooling performance of the water-cooling type cooler is improved without extending the cooling pin, an increase in the weight of the water-cooling type cooler can be reduced and a fabrication cost of the water-cooling type cooler can be reduced.

Abstract: The present invention is related to a hybrid fault current limiter comprising a switching unit detaching a moving contact located on a cable and transmitting a trip signal if a fault current is flowed at an electric power system, a semiconductor switching unit connected in series with the switching unit and configured to be turned off to limit the flow of the fault current when the trip signal is transmitted, and a circuit breaking unit connected in parallel to the switching unit and the semiconductor switching unit and configured to limit the fault current detoured from the switching unit and the semiconductor switching unit. The present invention provides rapid treatment for the fault current problem by applying the algorithm sensing the occurrence of the fault current and the algorithm limiting the fault current simultaneously.

Abstract: The present disclosure relates to an RFID (Radio frequency identification) tag for metallic materials, including a dielectric substrate, a tag chip arrayed on the dielectric substrate for storing an object data, a feeding loop connected across the tag chip for forming an inner space, and a metallic radiator connected across the feeding loop for receiving an electromagnetic signal from outside.

Abstract: A safety-extension base connected to a main base and a control method thereof are disclosed, the base includes a communication unit, a system state monitoring unit, a module control unit, a memory unit, a state conversion unit and a safety-processing unit. The communication unit performs data communication with the main base. The system state monitoring unit monitors a state of the PLC system. The module control unit controls a general operation of the safety-extension base and outputs different cases of control signals. The memory unit stores the data transmitted from the main base and a program and information. The state conversion unit converts the state of the safety-extension base into the normal state or safety state. The safety-processing unit performs a control of the safety-extension base.

Abstract: Disclosed is a vector modulator. The vector modulator can control the amplitude and phase of an input signal, by not using amplitude variable attenuators but using phase shifters. Further, the vector modulator has a simple configuration and enables an input signal to be exactly modulated. Furthermore, the vector modulator can modulate the phase of an input signal throughout all areas in the polar coordinate system.

Abstract: The present invention relates to a high-voltage gas circuit breaker, and there is provided a gas circuit breaker including a movable arc contact and a fixed arc contact engaged with the movable arc contact; a cylinder rod coupled with the movable arc contact; an insulating rod connected to the cylinder rod through a link mechanism in which an end thereof is connected to an operating mechanism; and an ejection nozzle for ejecting an arc-extinguishing gas between the movable arc contact and the fixed arc contact, wherein the link mechanism is reduced in a length direction of the insulating rod to pull the cylinder rod to a side of the insulating rod when the insulating rod is moved apart from the cylinder rod.

Abstract: Disclosed is a position indicating device for a pull-out type circuit breaker used to cut off a current, the position indicating device including a position indicating plate installed at a lower surface of the circuit breaker to be rotatable up and down and having an arrow marked thereon, an indication supporter installed at a cradle and having stepped pressing surfaces for pressing up the position indicating plate, and a frame portion of a movable carriage, the frame portion having windows for externally showing a rotated state of the position indicating plate, whereby when the circuit breaker is docked with the cradle, the position indicating plate is rotated by the indication supporter so as to indicate the position of the circuit breaker through the windows, thereby allowing a fast and precise recognition of the position of the circuit breaker.

Abstract: Disclosed are a valve for a gas circuit breaker, and a gas circuit breaker having the same. The gas circuit breaker comprises a cylinder constituting appearance of the gas circuit breaker, and providing a gas flow path therein, a partition plate having passing holes, and configured to partition inside of the cylinder, a sleeve concentrically disposed in the cylinder, a valve body inserted into the sleeve, and mounted below the partition plate so as to perform a reciprocation along the sleeve, an elastic means configured to upwardly apply an elastic force on a bottom surface of the valve body, and a blocking plate inserted into the sleeve, and mounted between the valve body and the partition plate so as to be moveable in upper and lower directions, wherein the valve body is provided with discharge openings, and the discharge openings are open and closed by movements of the blocking plate.

Abstract: Disclosed is a gas insulation circuit breaker with a structure for decreasing friction. The gas insulation circuit breaker comprises: a movable side supporting plate; a cylinder mounted so as to perform a reciprocating movement in a state that an outer surface thereof comes in contact with an inner surface of the movable side supporting plate; a contact spring for conduction disposed between the movable side supporting plate and the cylinder; and a movable arc contactor and a fixed arc contactor installed at the movable side supporting plate and the cylinder, respectively, and contacting and separated from each other by movement of the cylinder, wherein an end of the cylinder is tapered, and the outer surface of the cylinder comes in contact with the contact spring for conduction after a predetermined time lapses in a state that the cylinder has started to perform a closing operation during a circuit breaking operation.

Abstract: Disclosed are a position indicating apparatus for a circuit breaker and a circuit breaker having the same. The circuit breaker having a position indicating apparatus comprises a cradle having a bus bar terminal and a load terminal; a main body having a bus bar connection unit and a load connection unit respectively connected to the bus bar terminal and the load terminal, and configured to be movable to a run position that the terminals and the connection units are connected to each other, and to a test position that the terminals and the connection units are separated from each other; and a position indicating apparatus configured to outwardly display a position of the main body by interworking with motion of the main body, wherein the position indicating apparatus comprises: a movable pin interworking with motion of the main body; and a display unit configured to display a position of the main body corresponding to a position of the movable pin by interworking with motion of the movable pin.

Abstract: Disclosed is a bushing terminal of a vacuum circuit breaker used for interrupting current, which includes: a terminal body having a cylinder that can be inserted into the interior of a contactor and annular protrusions formed to be protrude from an outer circumferential surface of the cylinder; and a flange having an insertion hole through which the cylinder is inserted, wherein the annular protrusions are plastic-deformed so as to be fixed to the insertion hole of the flange.

Abstract: Disclosed is a device for preventing withdrawing and inserting of a circuit breaker. The device for preventing withdrawing and inserting of a circuit breaker include: a lead screw is coupled between a carriage and a girder assembly and rotated by an external force to allow a breaker body to be closed or released while the carriage is moved with respect to a cradle, and a braking unit preventing the lead screw for operating when the girder assembly is released from the cradle. In an unstable state in which the girder assembly is not coupled to the cradle, a withdrawal handle is prevented from being inserted into the girder assembly. Therefore, an abnormal withdrawing operation can be prevented, and thus, various safety accidents, a contact resistance and temperature rise, damage to a device due to electrical breakdown can be prevented.

Abstract: A noise measurement system in a power stabilization network, a variable filter applied to the power stabilization network, and a method for measuring noise in the power stabilization network are provided. A power line communication signal from the power stabilization network is attenuated relative to a particular frequency using a filter in order to allow the power line communication signal to operate within an input range of an Electromagnetic Interference (EMI) measurer. A signal from a forbidden frequency band is transmitted to the EMI measurer without any attenuation or influence on a noise floor.

Abstract: A trip device is disclosed, the device comprising: a power source side heater connected to a power source side of a molded case circuit breaker (MCCB) to receive current; a load side heater connected to a load side of the MCCB to receive the current; and a bimetal including a direct heat unit contacting the power source side heater and an indirect heating unit facing the power source side heater, wherein the bimetal is partially fixed between the power source side heater and the load side heater and is curved when over-current or short-circuited current flows in the MCCB.